METHODS AND KEY TO RATINGS
Preferred Practice Pattern guidelines should be clinically relevant and specific enough to provide useful information to practitioners. Where evidence exists to support a recommendation for care, the recommendation should be given an explicit rating that shows the strength of evidence. To accomplish these aims, methods from the Scottish Intercollegiate Guideline Network1 (SIGN) and the Grading of Recommendations Assessment, Development and Evaluation2 (GRADE) group are used. GRADE is a systematic approach to grading the strength of the total body of evidence that is available to support recommendations on a specific clinical management issue. Organizations that have adopted GRADE include SIGN, the World Health Organization, the Agency for Healthcare Research and Policy, and the American College of Physicians.3
- All studies used to form a recommendation for care are graded for strength of evidence individually, and that grade is listed with the study citation.
- To rate individual studies, a scale based on SIGN1 is used. The definitions and levels of evidence to rate individual studies are as follows:
High-quality meta-analyses, systematic reviews of randomized controlled trials (RCTs), or RCTs with a very low risk of bias
Well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias
Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias
High-quality systematic reviews of case-control or cohort studies
High-quality case-control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal
Well-conducted case-control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal
Case-control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal
Nonanalytic studies (e.g., case reports, case series)
- Recommendations for care are formed based on the body of the evidence. The body of evidence quality ratings are defined by GRADE2 as follows:
Further research is very unlikely to change our confidence in the estimate of effect
Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Any estimate of effect is very uncertain
- Key recommendations for care are defined by GRADE2 as follows:
Used when the desirable effects of an intervention clearly outweigh the undesirable effects or clearly do not
Used when the trade-offs are less certain-either because of low-quality evidence or because evidence suggests that desirable and undesirable effects are closely balanced
- Key recommendations for care ratings are listed in the Highlighted Findings and Recommendations for Care section. A key recommendation may address an area of controversy for which there is insufficient evidence to make a recommendation.
- Literature searches to update the PPP were undertaken in February 2010 in PubMed and the Cochrane Library. Additional searches were undertaken in March 2010; searches were last updated in January 2011. Complete details of the literature search are forthcoming.
HIGHLIGHTED FINDINGS AND RECOMMENDATIONS FOR CARE
Cataract is a progressive, chronic, age-related disease affecting a large number of people over the age of 50. Cataract surgery is one of the most highly successful treatments in the history of medicine. Without surgery, patients would experience steady decline in visual and physical function. With surgery, patients rapidly recover with excellent vision and the ability to resume regular activities of daily living. The planning and decision-making process for cataract surgery is complex and intricate, involving not only judgment about appropriate treatment and surgical techniques but also about antibiotic, prophylaxis, device selection (intraocular lenses [IOLs], ophthalmic viscosurgical devices [OVDs]), and prevention of complications. Continued innovation in surgical technique, IOLs, and antibiotic prophylaxis has improved safety and efficacy. The following list highlights important findings and recommendations for care from this comprehensive revision of the PPP.
1. Cataract surgery should be recommended when indicated because of proven effectiveness in enhancing quality of life. (strong recommendation, moderate evidence)
Numerous studies have documented that cataract extraction can markedly improve a patient's activities of daily living.4-7 These activities may include basic functions such as walking, driving, maintaining an occupation, and caring for personal needs; they may also extend to hobbies, enabling participation in social and community activities, and the reduction of ocular imbalance and troublesome refractive states.5,8-13 Scientific literature further provides support for a decreased risk of injury from falls and automobile accidents, improved mental health, and a general sense of well-being following cataract surgery.14-20 Such improvements in overall quality of life cannot be predicted or judged solely by single measures of visual function such as Snellen acuity, because problems with glare, contrast sensitivity, color perception, aberration, and binocularity directly impact a patient's level of visual impairment.8,9,21-26
2. Cataract surgery should be recommended when indicated because of its cost-effectiveness in relation to other accepted treatments. (strong recommendation, moderate evidence)
The medical advances in cataract surgery from the late 1960s to present have resulted in increased safety and improved outcomes. One estimate of the present benefit value of cataract surgery is $95,000,27 which is far greater than the cost of treatment at $2300 to $3000. This value compares favorably with the estimated present values for other treatments: $20,000 for breast cancer, $6000 for depression, $240,000 for a low-birthweight infant, and $70,000 for a heart attack. These various analyses demonstrate that on a relative basis, cataract surgery is very cost-effective and beneficial for the patient and society.
3. The decision to recommend cataract surgery should be based on consideration of the following factors: visual acuity, visual impairment, and potential for functional benefits. (strong recommendation, good evidence)
There is no single test or measure that adequately describes the effect of a cataract on a patient's visual status or functional ability.28 Therefore, no single test can properly define the threshold for performing cataract surgery. Though various methods of acuity measurement have long been considered the primary determinant for surgical appropriateness, the decision to recommend cataract surgery should not be made solely on this basis.4,23 For example, surgery for nonadvanced cataract in symptomatic patients with relatively good Snellen visual acuity often provides significant functional benefits.29 Standardized evaluation of impairment of visual function and activities of daily living has been shown to correlate with expected improvement and satisfaction after cataract surgery. Several of these validated testing instruments and recent modifications are available for clinical use.4,23,24,30-33
4. Cataract surgery is a procedure appropriately utilized in the United States.
(strong recommendation, moderate evidence)
Cataract extraction ranks among the most commonly performed surgical interventions in the United States. Assessment of appropriateness is therefore of particular interest and importance. Several studies of cataract surgery in the United States have shown utilization to be appropriate in the majority of cases evaluated.34 The primary indication for surgery is visual function that no longer meets the patient's needs, and for which cataract surgery provides a reasonable likelihood of improved vision. Preoperative evaluation to identify appropriate candidates should include thorough ophthalmic examination, patient-centered visual function evaluation, and patient education about treatment options prior to consent for surgery.
5. Ophthalmologists and other physicians managing patients taking alpha-antagonists should be aware of the risks of intraoperative floppy iris syndrome (IFIS). (strong recommendation, good evidence)
Intraoperative floppy iris syndrome is associated with a higher rate of surgical complications, particularly when it is not recognized or anticipated.35-39 Pupil stretching and sphincterotomies are ineffective in these eyes, and pharmacologic approaches, such as intracameral epinephrine, viscomydriasis, and pupil expansion devices, either alone or in combination, should be used to manage IFIS.35-37 Patients should be questioned about current or prior use of alpha-antagonists in general and tamsulosin in particular. The risk of IFIS is greater with tamsulosin than with nonselective alpha-antagonists.40
6. The intraocular pressure (IOP) lowering effect of cataract surgery should be considered in the overall management of the patient. (strong recommendation, moderate evidence)
Phacoemulsification cataract surgery alone has been shown to reduce IOP in patients without glaucoma.41-44 It also has been shown to be of benefit in lowering IOP in patients with angle-closure glaucoma.45-47 In patients with open-angle glaucoma, the IOP lowering associated with phacoemulsification cataract surgery alone may be of limited benefit.45,48
7. Ophthalmologists should be aware of increased antibiotic resistance in the general population. (strong recommendation, moderate evidence)
While staphylococcal species have been shown to be the most common organism cultured from cases of postoperative infectious endophthalmitis,49-51 increasing resistance of these organisms to commonly used antibiotics is a major concern today.52-55 What started as penicillin resistance has progressed over time to common resistance for many antibiotics, including all of the presently used fluoroquinolones.52-55 These multidrug resistant bacteria have become so common that they are now present in the majority of patients who come for routine cataract surgery in many regions of the United States today.56
8. The optimum dosing and route of administration of antibiotics should be considered in order to achieve a high intraocular concentration immediately following surgery. (strong recommendation, moderate evidence)
With bacterial resistance an ever growing problem, it is becoming increasingly important to ensure that high concentrations of currently available antibiotics are present inside the eye, where a bacterial inoculum might reside. Although topical antibiotics may reach intraocular therapeutic levels for many bacteria, only intracameral antibiotics at the end of the case guarantees suprathreshold antibiotic levels for an extended period of time.57 Evidence that this approach is efficacious is growing.58-60 Topical antibiotic eyedrops can be additive to intracameral antibiotics; however, if used alone they should be given frequently the day of surgery and not held until the next day.61-65 There is less evidence that subconjunctival antibiotics are equally efficacious when compared with topical and intracameral antibiotics.66
9. Although the incidence is rare, ophthalmologists should be aware of the potential risk of toxic anterior segment syndrome (TASS). (strong recommendation, moderate evidence)
In one large series of 26,408 consecutive cataract surgeries, the incidence of TASS was 0.22%.67 An evaluation of common risk factors associated with TASS looked at submitted TASS questionnaires and results from site visits from 2006 through 2009. The most common factors associated with TASS were related to inadequate cleaning and sterilization of ophthalmic instruments, such as insufficient flushing of phacoemulsification and irrigation/aspiration handpieces, as well as the use of enzymatic cleaners, detergents, and ultrasound baths68
10. Absent a normal capsular bag, ophthalmologists should determine whether the power and design of an IOL intended for capsular bag fixation is or is not appropriate for ciliary sulcus placement. (strong recommendation, moderate evidence)
Optimal characteristics of a sulcus-fixated posterior chamber intraocular lens include sufficient overall length, posterior haptic angulation, and the absence of sharp anterior optic edges.69 Intraocular lenses, such as single-piece acrylic designs that are intended solely for the capsular bag, should not be placed in the ciliary sulcus because they have been associated with pigment dispersion, elevated IOP, intraocular hemorrhage, and cystoid macular edema. Backup IOLs in appropriate powers, sizes, and designs should be available for every cataract procedure.69-71 Anticipating a more anterior location of the optic, the power of an IOL placed in the ciliary sulcus should be reduced relative to that calculated for the same IOL when placed in the capsular bag (but less so when capture of the optic posterior to the capsulorrhexis can be achieved).72,73 Optic capture also reduces reliance on adequate haptic length to provide optic centration and stability.74 Because noncapsular bag fixation may increase the potential for optic tilt and decentration, the surgeon should reconsider whether multifocal IOLs or those with higher degrees of negative spherical aberration should be implanted.75,76
11. Safety protocols should be in place to prevent the occurrence of wrong-site surgery. (strong recommendation, moderate evidence)
Steps taken before the surgery day, on the day of surgery, and when procedures dependent on preoperative calculation are undertaken can minimize the incidence of preventable surgical errors such as surgical site (e.g., wrong eye) and surgical procedure (e.g., wrong IOL implant).77-82 The Wrong-Site Wrong-IOL Checklist (see Appendix 3) is an example of how to document in the surgery chart that all the appropriate steps have been taken in preventing wrong-site and wrong-surgery events.
A cataract is a degradation of the optical quality of the crystalline lens (ICD-9 #366.1x).
PATIENT POPULATION DEFINITION
Adults (18 years old and older) with cataracts.
- Identify the presence and characteristics of a cataract
- Assess the impact of the cataract on the patient’s visual and functional status and on quality of life
- Educate the patient about the impact of a cataract on vision, functional activity, and natural history as well as the benefits and risks of surgical and other alternatives so that the patient can make an informed decision about treatment options
- Establish criteria for a successful treatment outcome with the patient
Perform cataract surgery when there is the expectation that it will benefit the patient’s function and when the patient elects this option
- Perform surgery when indicated for management of coexistent ocular disease
- Provide necessary postoperative care, rehabilitation, and treatment of any complications
Cataracts are the leading cause of blindness worldwide and remain an important cause of blindness and visual impairment in the United States, accounting for approximately 50% of visual impairment in adults over the age of 40.83 Cataracts are the leading cause of treatable blindness among Americans of African descent age 40 and older and are the leading cause of visual impairment among Americans of African, Hispanic/Latino, and European descent.83,84
There are several different types of cataracts: nuclear, cortical (spokelike), subcapsular (anterior and posterior), and mixed. Each type has its own anatomical location, pathology, and risk factors for development. Several systems are available to classify and grade lens opacities.85-89 Nuclear cataracts consist of a central opacification or coloration that interferes with visual function. There are different types of nuclear cataracts, accompanied by either brunescence, opalescence, or both.90 Nuclear cataracts tend to progress slowly and affect distance vision more than near vision. In advanced cases, the lens becomes brown and opaque.
Cortical cataracts can be central or peripheral and sometimes are best visualized by retroillumination or retinoscopy. Patients with this type of cataract commonly complain of glare. When the entire cortex becomes white and opaque, the cataract is referred to as a mature cortical cataract.
Posterior subcapsular (PSC) cataracts can cause substantial visual impairment if they affect the axial region of the lens. Posterior subcapsular cataracts are found more often in younger patients than are nuclear or cortical cataracts. Patients often have glare and poor vision with bright lighting, and their near vision is typically more affected than distance vision. Two population-based studies found that of the three types, PSC cataracts are associated with the greatest rate of cataract surgery.91,92 In an older population (mean age 79 years) undergoing cataract surgery, however, nuclear cataracts were most frequently encountered.93
Cataract affects over 22 million Americans age 40 and older, or about 1 in every 6 people in this age range. By age 80, more than half of all Americans have cataracts.94 The Eye Diseases Prevalence Research Group estimated that the number of individuals with cataracts will increase by 50% by 2020, based on U.S. Census population estimates.83
Studies have found racial differences in the prevalence of different cataract types. In the Salisbury Eye Evaluation Study, Americans of African descent had a four times greater chance of having cortical opacities than Americans of European descent, and Americans of European descent were more likely to have nuclear and PSC opacities.95 The Los Angeles Latino Eye Study of individuals 40 years old or older found that cortical opacities were the most frequent type of lens opacity.96
Numerous potential risk factors have been linked with cataract development and are listed in Table 1. The most common risk factors include diabetes mellitus; long-term topical, systemic, or inhaled oral corticosteroids; and prior intraocular surgery.97-109
TABLE 1. Risk Factors Associated with Increased Risk of Cataracts (PDF 92k)
Most studies are observational and can strongly suggest an association, but they cannot prove a causative effect because they did not measure cataract development or exposure to the risk factor in a standardized fashion.97,110
The natural history of all types of cataracts is variable, unpredictable, and related in some ways to type. Any portion of the lens can become opaque. With age, the lens increases in thickness and weight. Continued production of lens fibers causes hardening and compression of the nucleus, known as nuclear sclerosis. Subsequently, the lens proteins undergo modification and aggregation, and they take on a yellow-to-brown coloration, changing the transparency and refractive index of the lens. Nuclear sclerosis and yellowing are considered a normal part of the aging process.
Cataract is a progressive disease. Once visual acuity and function start declining, the natural history is a steady decline without any chance of recovery. In three studies, which used different scales for progression of cataracts, there is evidence that cataracts progress over time. In the Barbados Eye Studies, individuals with pre-existing lens opacities had cumulative 9-year progression rates of 22.0% for cortical, 17.8% for nuclear, and 25.8% for PSC opacities.111 The Melbourne Visual Impairment Project reported cumulative 5-year progression rates of 14.3% for cortical, 19.3% for nuclear, and 20.0% for PSC opacities.112 In the Longitudinal Study of Cataract, individuals with pre-existing lens opacities had cumulative 5-year progression rates of 16.2% for cortical, 45.8% for nuclear, and 55.1% for PSC opacities.113,114
Several studies show a linkage of smoking with nuclear sclerosis and demonstrated a dose-response effect.115-124 Findings from studies indicate a reduced risk of cataracts in past smokers compared with current smokers, demonstrating a benefit from smoking cessation.115,118,124,125 Thus, smoking cessation is a reasonable precaution to recommend to patients.
Cumulative lifetime exposure to ultraviolet-B radiation has been associated with lens opacities126-131; therefore, brimmed hats and ultraviolet-B blocking sunglasses are reasonable precautions to recommend to patients.132
A systematic review and eight randomized controlled trials of nutritional or vitamin supplementation published after the systematic review showed no significant effect in delaying the onset or progression of cataracts.133-141 Another trial had inconclusive results because a statistically significant protective effect of supplementation with vitamins C and E and beta-carotene was found in the study arm with U.S. participants, but no effect was noted in the study arm with United Kingdom participants.142After 9 years of follow-up, a randomized trial of multivitamin/mineral supplementation found fewer nuclear cataracts but more PSC cataracts in the group taking supplements compared with the placebo group.143 A trial conducted in a nutritionally deficient population in rural China did show a beneficial effect of supplementation.144 This trial was designed as a cancer intervention study, and participants had eye examinations only at the end of the study. Because this population had chronic deficiencies of multiple nutrients, the results may not be generalizable to better-nourished populations. Appendix 2 summarizes studies of nutrition and cataracts. An Evidence-based Practice Center systematic review of the literature sponsored by the Agency for Health Research and Quality found no benefit from multivitamin/mineral supplements in preventing cataracts.141 In those patients taking vitamin/mineral supplements of the formulation used in the Age Related Eye Disease Study, none of the vitamin/mineral supplements appear to demonstrate a beneficial effect on cataractogenesis to date.133-138,168 Therefore, no recommendations for the use of nutritional supplements to prevent cataracts or delay progression can be made at this time. If asked, ophthalmologists should counsel patients that there are no preventive nutritional supplements for cataract.
Three recent studies evaluated the use of statins to reduce incidence of cataract. One study, a prospective cohort study, concluded there was an increased incidence of cataract in patients taking any of the statin formulations.169 The Beaver Dam Study and another prospective cohort study reached the opposite conclusion, that statin use appears to decrease cataract risk.170,171
Long-term users of inhaled or oral corticosteroids are at higher risk for cataract formation.98-102
Patients with diabetes mellitus are at higher risk for cataract formation,103-105 and so prevention and proper treatment of type 2 diabetes may have the additional benefit of reducing the risk of cataract.
VISUAL FUNCTION AND QUALITY OF LIFE
The multiple components of visual function include central near, intermediate, and distance visual acuity; peripheral vision; visual search; binocular vision; depth perception; contrast sensitivity; perception of color; adaptation; and visual processing speed.8,21,22Visual function also can be measured in terms of functional disability caused by visual impairment.9,23-26 Many activities of daily living require function of more than one of these visual components.
Improved function and quality of life are the treatment outcomes that are most critical and applicable to the patient. In well-designed observational studies, cataract surgery consistently has been shown to have a significant impact on vision-dependent function; up to 90% of patients undergoing first-eye cataract surgery note improvement in functional status and satisfaction with vision.4-7 Several studies have reported an association between improved visual function after cataract surgery and an improved health-related quality of life.5,8-13Visual function plays an important role in physical function and well-being,14-17 particularly in terms of mobility.12,172,173 The loss of visual function in the elderly is associated with a decline in physical and mental functioning as well as in independence in activities of daily living,174,175 including night-time driving, daytime driving, community activities, and home activities. A long-term (10-year) evaluation of patients in the Blue Mountain Study found that cataract surgery patients had a significant improvement in the mental health domain scores from the SF-36 questionnaire.176 Cataract surgery may also improve insomnia.177,178
Visual impairment is an important risk factor for falls18,19 and for hip fracture20; poor depth perception and decreased contrast sensitivity have been found to independently increase the risk of hip fracture.179 In a randomized controlled trial, first-eye cataract surgery was found to reduce the rate of falling and fracture by 34% over a 12-month period.12 Similar improvement following second-eye surgery has also been confirmed.173 Visual loss from cataracts and the increased risk of falls may be a contributing factor for nursing home placement.180Visual impairment, in particular a decrease of visual acuity and contrast sensitivity, has been shown to be associated with difficulties in driving.22,181-184 Drivers with visually significant cataracts were 2.5 times more likely to have had an at-fault involvement in a motor vehicle crash over a 5-year period compared with drivers without cataracts.185 When older adults with cataracts who have undergone surgery are compared with those who did not undergo surgery, motor vehicle crash rates in the 4 to 6 years of follow-up were halved in the surgery group.186 One large study found that in an assessment of patients' visual function pre- and postoperatively, the largest improvements were noted for "driving during the day," "self-care activities," and "driving during the night."187
In summary, there are numerous studies showing that physical function, mental health, emotional well-being, safety, and overall quality of life can be enhanced when visual function is restored by cataract extraction.
Improved visual function as a result of cataract surgery can be characterized by the following:
- Better optically corrected vision
- Better uncorrected vision with reduced eyeglass dependence
- Increased ability to read or do near work
- Reduced glare
- Improved ability to function in dim levels of light
- Improved depth perception and binocular vision by elimination of anisometropia and achievement of good functional acuity in both eyes
- Improved color vision
Improved physical function as a critical outcome of cataract surgery can be characterized by the following:
- Increased ability to perform activities of daily living
- Increased ability to continue or resume an occupation
- Increased mobility (walking, driving)
Improved mental health and emotional well-being as a second critical outcome of cataract surgery includes the following benefits:
- Improved self-esteem and independence
- Increased ability to avoid injury
- Increased social contact and ability to participate in social activities
- Relief from fear of blindness
PATIENT OUTCOME CRITERIA
Outcome criteria can vary for each patient, depending on the patient’s needs, lifestyle, and medical condition. In general, outcome criteria include the following:
- Reduction of visual symptoms
- Improvement in visual function
- Achievement of desired refractive outcome
- Improvement in physical function, mental health, and quality of life
The purpose of the comprehensive evaluation of a patient whose chief complaint might be related to a cataract is to determine the presence of a cataract, confirm that a cataract is a significant factor contributing to the visual impairment and symptoms described by the patient, and identify other ocular or systemic conditions that might contribute to visual impairment or affect the cataract surgical plan or ultimate outcome.
Evaluation of Visual Impairment
The impact of a cataract on visual function can be subjectively assessed by self-reported functional status or difficulty with vision. The latter may be measured by tests of contrast sensitivity, glare disability, or visual acuity. With newer technology, it is also possible to objectively measure higher-order aberrations from cataracts that compromise visual acuity and quality.188,189 Over time, patients adapt to their visual impairment and may fail to notice functional decline that accompanies the insidious progression of a typical cataract.
There is no single test or measure that adequately describes the effect of a cataract on a patient's visual status or functional ability.28 Similarly, no single test can properly define the threshold for performing cataract surgery. The Snellen visual acuity chart is an excellent method for testing distance refractive error (e.g., myopia, hyperopia, astigmatism) in healthy eyes, and it is in wide clinical use. Although poor preoperative visual acuity does correlate with significant postoperative functional improvement in many patients with cataract,28 testing only at distance with high-contrast letters viewed in dark-room conditions will underestimate the functional problems in common real-life situations. These may include reading, especially in poor-contrast environments, day-time or night-time glare conditions, halos and starbursts at night, and impaired optical quality causing monocular diplopia and ghosting.23 Because preoperative visual acuity alone may be an unreliable predictor of postoperative functional improvement, the decision to recommend cataract surgery should not be made solely on the basis of Snellen visual acuity.4,30
Studies have indicated that measures of functional impairment related to vision provide valid and reliable information that is not reflected in the measurement of visual acuity.24,31-33For example, visual functional status indices such as the Activities of Daily Vision Scale (ADVS) and the Visual Function Index (VF-14) have been shown to correlate more strongly with functional improvement and satisfaction with vision after cataract surgery than does Snellen visual acuity.23Two main categories of validated questionnaires for measuring function exist: those that measure general health status (e.g., Short Form-36,190 Sickness Impact Profile,191and Quality of Well-Being Scale33) and those that are vision-specific measures. Questionnaires that measure general health status are less strongly correlated with improvement following cataract surgery than are disease-specific measures.33,192 Vision-specific instruments developed or used for cataract evaluation include one by Bernth-Peterson,193 the Visual Activities Questionnaire,21 the ADVS,31 the VF-1423 and modified versions (e.g., VF-8R),194 the National Eye Institute Visual Function Questionnaire (NEI-VFQ),195,196 and the Catquest-9SF.25 These questionnaires have been utilized as research tools to provide a standardized approach to assessing visual function, which can be analyzed and compared across time periods and populations. Questionnaires used alone are not intended to be the sole basis for determining the need for surgery. For example, some patients with clinically significant cataract who would experience worthwhile visual gain from surgery may not perceive a functional problem listed on the questionnaire.197 However, visual function questionnaires can contribute to the overall evaluation of a patient who has a cataract, and they may aid in the therapeutic decision-making process. At this time, there is no single universally accepted questionnaire in clinical use for assessing functional-vision impairment. The assessment of functional status, which may be performed using a variety of methods, is a pertinent part of the patient's evaluation. Patients who are least aware of their visual impairment typically have fairly symmetric cataract formation.
The comprehensive evaluation (history and physical examination) includes those components of the comprehensive adult medical eye evaluation198 specifically relevant to the diagnosis and treatment of a cataract as listed below.
- Patient history, including the patient's assessment of functional status, pertinent medical conditions, medications currently used, and other risk factors that can affect the surgical plan or outcome of surgery (e.g., immunosuppressive conditions, systemic alpha-1 antagonists, diabetes)
- Visual acuity with current correction (the power of the present correction recorded) at distance and, when appropriate, at near
- Measurement of best-corrected visual acuity (with refraction when indicated)
- External examination (eyelids, lashes, lacrimal apparatus, orbit)
- Examination of ocular alignment and motility
- Assessment of pupillary function
- Measurement of intraocular pressure (IOP)
- Slit-lamp biomicroscopy of the anterior segment
- Dilated examination of the lens, macula, peripheral retina, optic nerve, and vitreous
- Assessment of relevant aspects of the patient's mental and physical status
Supplemental Ophthalmic Testing
Supplemental preoperative ophthalmic tests are not specific for a cataract but may help to identify both the cause and level of severity of an individual's visual symptoms as well as the extent to which comorbidities may be contributing to these symptoms. In a large majority of patients, the ophthalmologist is able to determine whether the cataract is responsible for the patient's visual loss by correlating slit-lamp biomicroscopy findings with the patient's specific symptoms.
Occasionally, a patient presents with visual symptoms that are disproportionate to the degree of cataract formation. Visual acuity testing alone does not quantify certain visual symptoms, such as disabilities due to glare and reduced contrast sensitivity.193,199-203 In addition, measurements taken in a darkened examination lane with a high-contrast, brightly illuminated target may significantly underestimate the functional problems experienced under a wide variety of lighting and contrast conditions.
Glare testing determines the degree of visual impairment in the presence of a light source located in the patient's visual field. Cataracts may produce a severe visual disability in brightly lit situations such as ambient daylight or from oncoming automobile headlights at night. Visual acuity in some patients with cataracts may be normal or near normal when tested in a dark examination room, but when these patients are retested together with a source of glare, visual acuity (or contrast sensitivity) may drop significantly.204
Contrast sensitivity testing measures the eye's ability to detect subtle variations in shading by using figures that vary in contrast, luminance, and spatial frequency and is a more comprehensive but time-consuming measure of visual function than Snellen visual acuity testing. For the patient who complains of visual loss and also has lens changes, contrast sensitivity testing may demonstrate a significant loss of visual function not appreciated by Snellen visual acuity testing alone.199-202,205,206 Decreased contrast sensitivity (as well as decreased Snellen visual acuity) may occur for a number of reasons, and therefore, this test is not a specific indicator of visual loss due to a cataract. In spite of substantial progress over the past few years, there remains no standard or universally preferred method for testing contrast sensitivity.
Ocular wavefront testing has demonstrated that even relatively mild cataracts may be associated with a significant increase in visual aberrations. For example, the naturally occurring negative spherical aberration of the crystalline lens, which offsets the stable and naturally occurring positive spherical aberration of the cornea, typically changes to positive spherical aberration later in life with cataract formation, leading to a decrease in contrast sensitivity.207,208 This may explain the symptoms reported by some older individuals with a mild lens opacity and reasonably good best corrected visual acuity (BCVA).
Biomicroscopic and ophthalmoscopic examinations of the macular region do not necessarily predict macular function when the macula is abnormal. Potential acuity testing attempts to predict the visual acuity following cataract surgery, and it may contribute helpful adjunct information in these situations.209,210Potential acuity tests are most accurate in patients with mild to moderate cataracts in the absence of concomitant retinal disease. However, these tests perform less reliably in patients with cataract who present with visual acuity worse than 20/100.209,211-213
Subjective potential acuity tests can be divided into two categories. The Guyton-Minkowski Potential Acuity Meter, laser interferometer, and scanning laser ophthalmoscope project an image onto the retina through relatively clear regions of the lens, and the patient is asked to identify the letters or pattern.214 Other tests such as the Retinal Acuity Meter (formerly the Illuminated Near Card) and potential acuity pinhole require the patient to read a brightly illuminated near card through a trial frame that combines their near eyeglass correction with a pinhole.209,213,215,216 The near-card pinhole methods are simpler and less expensive and may give better accuracy in the absence of ocular comorbidity than the technology-dependent Guyton-Minkowski Potential Acuity Meter and scanning laser ophthalmoscope. When the preoperative distance acuity is 20/100 or better, the Retinal Acuity Meter may be more likely to predict the postoperative visual acuity in the presence of ocular comorbidity correctly.213,215
Electrophysiologic testing (e.g., electroretinography and visual evoked potential) measures the electrical response to visual stimuli presented and indicates potential retinal function in nonverbal patients.
Specular microscopy and corneal pachymetry have been used to evaluate patients with known preoperative corneal disease in an effort to determine whether the cornea is likely to remain clear following cataract surgery. These tests are generally not needed, but they may be useful for eyes in which the corneal endothelial function is suspected to be abnormal as a result of endothelial corneal dystrophies, previous ocular surgery, or trauma. However, several studies suggest that specular microscopy has relatively low accuracy in predicting whether the cornea will remain clear following cataract surgery.217,218
Although not routinely necessary, assessment of the ocular surface with corneal topography may be useful to determine whether irregularities in corneal power and shape are contributing to visual impairment. Additionally, corneal topography is helpful in the assessment and management of regular and irregular astigmatism.
Optical coherence tomography (OCT)219,220 and diagnostic and fluorescein angiography may be helpful prior to cataract surgery for confirming normal foveal architecture or for identifying the presence of comorbid disease, even when the foveal center and immediately surrounding areas appear normal on direct examination.
B-scan ultrasonography is appropriate when a dense cataract precludes adequate visualization of the posterior segment or to confirm the presence of a posterior staphyloma. Visual fields, external and fundus photography, and special color-vision testing have not been shown to be of value in routinely evaluating patients before cataract surgery.
Management of a visually significant cataract is primarily surgical. Nonsurgical management includes counseling patients about cataract-related visual symptoms, providing reassurance about the cause of the visual disability, and prescribing new eyeglasses where appropriate.
At the present time, the best available evidence does not support a benefit from nutritional supplementation in preventing or delaying progression of cataracts; therefore, treatment with supplements is not recommended (see Appendix 2).141 Currently, there are no pharmacological treatments known to eliminate existing cataracts or retard their progression and, if asked, ophthalmologists should advise patients that nutritional supplements and pharmacological treatments are of no proven efficacy.
Patients may reduce their risk of cataract development or progression by modifying their exposure to risk factors, such as through cessation of smoking and tobacco use or improved control of diabetes.
Studies have found that a physician's advice to quit is an important motivator in attempting to stop smoking.221-224 Cataracts, therefore, give the ophthalmologist an opportunity to discuss and promote not only the ocular benefits but also the general health benefits of smoking cessation.
Patients who are long-term users of oral and inhaled corticosteroids should be informed of the increased risk of cataract formation99-102,151,225 and may wish to discuss alternative medications with their primary care physician. Brimmed hats and ultraviolet-B blocking sunglasses are reasonable precautions to consider recommending, but there is no interventional trial that proves that such intervention will reduce the risk of cataract formation.132,226
Indications for Surgery
The primary indication for surgery is visual function that no longer meets the patient's needs and for which cataract surgery provides a reasonable likelihood of improved vision. Other indications for a cataract removal include the following:
- Clinically significant anisometropia in the presence of a cataract
- The lens opacity interferes with optimal diagnosis or management of posterior segment conditions
- The lens causes inflammation or secondary glaucoma (phacolysis, phacoanaphylaxis)
- The lens induces angle closure (phacomorphic)
Contraindications to Surgery
Surgery for a visually impairing cataract should not be performed under the following circumstances:
- Tolerable refractive correction provides vision that meets the patient's needs and desires
- Surgery is not expected to improve visual function, and no other indication for lens removal exists
- The patient cannot safely undergo surgery because of coexisting medical or ocular conditions
- Appropriate postoperative care cannot be arranged
- The patient or patient's surrogate decision maker is unable to give informed consent for nonemergent surgery
Preoperative Medical Evaluation
The ophthalmologist who is to perform the cataract surgery has the following responsibilities:227,228
- To examine the patient preoperatively (see Ophthalmic Evaluation)
- To ensure that the documented evaluation accurately reflects the symptoms, findings, and indications for treatment
- To obtain informed consent from the patient or the patient's surrogate decision maker after discussing the risks, benefits, and expected outcomes of surgery, including the anticipated refractive outcome and the surgical experience229
- To review the results of the presurgical evaluation with the patient or the patient's surrogate decision maker
- To formulate a surgical plan, including selection of an appropriate IOL
- To formulate postoperative care plans and inform the patient or the patient's surrogate decision maker of these arrangements (setting of care, individuals who will provide care)
- To answer the patient's questions about the surgery and care, including associated costs
The best interest of the patient is served by having the operating ophthalmologist perform the preoperative evaluation, because this will allow the surgeon to formulate the surgical plan and to establish a relationship with the patient prior to surgery. Although the ophthalmologist is responsible for the examination and review of the data, certain aspects of data collection may be conducted by another trained individual under the ophthalmologist's supervision and with his or her review.227,228
All patients undergoing cataract surgery should have a history and physical examination relevant to the risk factors for undergoing the planned anesthesia and sedation and as directed by a review of systems. For patients with certain severe systemic diseases (e.g., chronic obstructive pulmonary disease, poorly controlled arterial blood pressure, recent myocardial infarction, unstable angina, poorly controlled congestive heart failure, or poorly controlled diabetes) a preoperative medical evaluation by the patient's primary care physician should be strongly considered.230
Laboratory testing as indicated by the findings in the history and physical examination is appropriate.231 The Study of Medical Testing for Cataract Surgery demonstrated that perioperative morbidity and mortality were not decreased by the use of routine medical testing. Preoperative testing should be recommended as appropriate for particular medical problems for a given surgical candidate, not as a routine practice.231,232
Biometry and Intraocular Lens Power Calculation
The accurate measurement of axial length and central corneal power, combined with an appropriate IOL selection based on a power calculation formula, is the minimal requirement to achieve the targeted postoperative refraction. A-scan ultrasonography or optical biometry is used to measure axial length. A-scan ultrasonography is performed using either an applanation or immersion technique. In A-scan ultrasonography by applanation, the ultrasound probe compresses the cornea by variable amounts and there is both a variable and artificial shortening of axial length; the accuracy and overall consistency of this method are highly dependent on the skill and experience of the operator.233-235 When the immersion technique is used, the ultrasound probe does not come in direct contact with the cornea, making the measurements more consistent.
Optical biometry is a high-resolution noncontact method for measuring axial length that uses a specialized light source rather than ultrasound. It is significantly more accurate and consistent than contact (applanation) A-scan biometry.233,236,237 Optical biometry was initially considered to be comparable to immersion A-scan biometry, but it has since been shown to produce improved refractive outcomes; the patient's spherical equivalent is more likely to be closer to the target refraction.238-240 Optical biometry has also been shown to give user-independent results.241 Other advantages over A-scan ultrasonography include ease and speed of automated operation and the ability to measure to the center of the macula when proper fixation is achieved. Because optical biometry measures the refractive axial length rather than the anatomic axial length, this method is more accurate than standard forms of ultrasound A-scan biometry when the fovea is located on the sloping wall of a posterior staphyloma.242 Additionally, it is easier to use optical biometry than ultrasound when the patient has silicone oil in the posterior segment.243,244 Despite recent advances in optical biometry that now allow the measurement of axial length through increasingly dense cataracts,245 A-scan biometry may be necessary to measure the axial length in certain cataracts or when patients are unable to fixate properly.246,247 The measurement and comparison of axial length for both eyes is advisable, even if surgery is not planned for the other eye.
Formulas for calculating IOL power rely on keratometry to determine the net refractive contribution of the cornea. These measurements can be obtained by either manual or automated keratometry, or through corneal topography. Following keratorefractive surgery, the determination of central corneal power is particularly difficult (see Cataract Surgery Following Refractive Surgery section). All devices that measure corneal power by standard methods are unable to accurately determine the central corneal power following keratorefractive surgery. The use of standard keratometry in this setting without a compensatory adjustment will typically result in an unanticipated refractive outcome.
Recent-generation theoretical IOL power calculation formulas such as Hoffer Q, Holladay, and SRK/T should be used in the IOL selection process.248-253 Some newer generation formulas, such as Haigis, Holladay 2, and Olsen, incorporate additional measurements such as anterior chamber depth, lens thickness, and horizontal corneal diameter in an attempt to predict more accurately the effective lens position of the IOL to be implanted. Theoretical formulas rely on numerical constants that allow the formula to predict the effective lens position within the eye. The Haigis formula uses three separate constants that are highly specific to the individual characteristics of a specific IOL model across its power range. Although the IOL manufacturer supplies lens constants to be used with calculation formulae, these numbers are generally considered to be only a recommendation and may not correspond to the biometry method being used. The eventual optimization of lens constants for a specific IOL based on an individual surgeon's actual refractive outcome is recommended.
The surgeon should consider the patient's individual desires and needs in selecting an appropriate postoperative refractive target. Depending on the manufacturer, a limited number of extended-range high plus and high minus IOL powers is available. For the patient with extreme myopia, very low-power IOLs that straddle both sides of plano may require unique lens constants for plus (+) and minus (-) powers that are quite different than those recommended by the manufacturer.254 For a patient with extreme hyperopia requiring an IOL power in excess of the available range, piggybacking two posterior chamber IOLs has been used.255 When this is required, it is preferable to use lens optics of different materials in different locations rather than inserting both IOLs within the capsular bag. This will reduce the risk of interlenticular (between the IOLs) membrane formation.256,257Intraocular lens power calculations for piggybacked IOLs as a primary procedure may be less accurate than for a single IOL, because it is difficult to predict the combined effective IOL position.258 Refractive results with piggybacking IOLs have been favorable in two small case series.259,260
Cataract surgery may be performed using a variety of anesthesia techniques that include general and local (regional) anesthesia (e.g., retrobulbar, peribulbar, sub-Tenons injection, topical, and intracameral). The planned mode of anesthesia should be discussed with the patient so that she or he will know what to expect in terms of pain, discomfort, consciousness level, visual experiences, and complications. The outcomes of cataract surgery measured in terms of visual acuity, visual function, complications, adverse medical events, and patient satisfaction have not been shown to vary significantly among anesthesia techniques.261-268
Local (regional) anesthesia is generally preferred, with or without sedation/analgesia. General anesthesia may be utilized if needed for those patients with medical, psychosocial, or surgical indications. In a review of studies on cataract surgery using local anesthesia, investigators have concluded that a variety of anesthesia strategies for cataract surgery are safe and effective and that they provide good or excellent intraoperative pain control.261,265-269
Anesthesia techniques with needle injections may be associated with complications such as strabismus, globe perforation, retrobulbar hemorrhage, intravascular or subarachnoid injection, and macular infarction not seen with topical, blunt cannula, and other non-needle injection techniques.261,265-269The risk of globe perforation by needle injection is increased with axial myopia and following scleral buckle placement.
Many patients who have cataract surgery under topical or peribulbar regional anesthesia (especially topical) experience a variety of visual sensations such as seeing lights, colors, movement of instruments, and the surgeon's hand or fingers. Because 3% to 18% of patients found these visual sensations disturbing, preoperative counseling about this phenomenon may make it less frightening.270,271
Intravenous access is generally recommended to treat potential adverse events when sedation/analgesic agents are administered.272 However, given the trend toward topical anesthesia and reduction or elimination of intravenous analgesia/sedation, IV access may not be routinely necessary. Monitoring during administration of anesthesia and surgery generally includes electrocardiogram, pulse oximetry, blood pressure, and respirations. These should be performed by personnel (other than the operating ophthalmologist) qualified to monitor and manage the patient's status. One study found that a patient's medical history, laboratory values, and electrocardiogram were not predictive of the need for intervention by anesthesia professionals, and intervention was required in 37% of all cataract cases.273 However, this study, in which all patients received a peribulbar block, did not document that any of the interventions by anesthesia personnel affected cataract surgery outcomes. In another study, monitored anesthesia care for 1957 cataract surgery cases was provided by registered respiratory practitioners who were trained as anesthesia assistants and who used topical anesthesia with or without IV sedation. Two studies reported on their experiences using registered nurses or registered respiratory practitioners trained as anesthesia assistants.274,275 Anesthesiologist consultation was required in 4% to 8% of the cases, and actual intervention by the anesthesiologist happened in less than 1% of the cases.
The review of studies using local anesthesia in cataract surgery found weak evidence to support the benefits of IV or intramuscular sedation or analgesia to improve pain relief, anxiety, or patient satisfaction.261 The evidence was insufficient to determine if any analgesic or sedation regimen was better than any other. The Study of Medical Testing for Cataract Surgery found that patients experienced more postoperative drowsiness and nausea when IV agents were used and that nausea and vomiting increased significantly with the number of agents (opioid, sedative, hypnotic) used.262 Also, excessive use of IV sedatives during cataract surgery was associated with increased risk of an adverse intraoperative medical event and was an even greater risk when both IV opiates and sedatives were used.263,276,277 The evidence is inconclusive on the value of oral anxiolytic medications to reduce the patient's anxiety levels when given before cataract surgery.276-278
In summary, given the lack of evidence for a single optimal anesthesia strategy for cataract surgery, the type of anesthesia management should be determined according to the patient's needs and the preference of the patient, the anesthesia professionals, and the surgeon.
Prevention is of great importance because of the potentially severe consequences of endophthalmitis. However, controlled studies of endophthalmitis prophylaxis have been difficult to perform due to the low incidence of endophthalmitis, varied practice patterns, inconsistent definitions, and the rapid evolution of surgical techniques. Two emerging concerns are the increasing resistance of Staphylococcus species (the most common cause of endophthalmitis) to a broad spectrum of antibiotics, including the latest generation fluoroquinolones, and the increased occurrence of acute endophthalmitis more than a week after surgery.52-55
Historically, the expected incidence of sporadic endophthalmitis has been between 0.5 and 1 case per thousand of routine cataract procedures. However, since 1994, an increased rate of postcataract surgery infections has been reported, while the incidence of infection after other anterior segment procedures has been on the decline.64,279-281 It has been proposed that the increased infection rates correspond to the increased use of clear corneal incisions for cataract surgery, because improperly constructed clear corneal incisions are more prone to postoperative instability, leakage, and a potential influx of microbes than are sclerocorneal incisions.282-289 On the other hand, four large case series found no greater likelihood of infection with corneal versus other types of incisions.50,290-292 Nevertheless, careful watertight incision construction and closure (with or without sutures) is obligatory, irrespective of surgical style, because the incidence of infection increases with wound leak.65 Other factors associated with increased rates of endophthalmitis include intraoperative rupture of the posterior capsule, vitreous loss, prolonged surgery, immunodeficiency, active blepharitis, lacrimal duct obstruction, inferior incision location, male gender, and older age.59,65,66,291,293-296
Three retrospective studies suggest a greater endophthalmitis incidence with a planned extracapsular cataract extraction (ECCE) when compared with cataract surgery by phacoemulsification.297-299 However, assuming proper incision closure, there is no evidence that the method of cataract surgery is a major factor affecting endophthalmitis risk.
There is also no consistent evidence that any one type of IOL optic material is associated with a higher rate of infection.59,284,299,300 However, polypropylene loop supports have been associated with a greater chance for infection because it appears that bacterial adherence to polypropylene exceeds that for other materials.301,302 As a corollary, it has been demonstrated that antibiotics reduce the tendency for microorganisms to adhere to the surface of IOLs.303,304 Also, there may be a greater risk for IOL-related contamination of the anterior chamber when the IOL comes in contact with the ocular surface prior to implantation. One study suggests that when the IOL is folded into an inserting cartridge and is placed within the eye directly through the cartridge, avoiding the ocular surface, the likelihood for intraocular contamination is reduced.305
While very occasional clusters of infections may be induced by contaminated surgical products306-309 or contaminated operating room environments,310,311 it has been established that the patient's periocular flora is the source of the microbes responsible for most cases of sporadic postoperative infection.312 Presumably the risk for endophthalmitis can be lessened by reducing the number of microbes on the ocular surface, by reducing the opportunity for microbes to reach the intraocular environment during or after surgery, or by eliminating those organisms that may have reached the eye intra- or postoperatively.
In accord with those concepts, prophylactic strategies that have been used include applying topical antibiotic eyedrops before surgery, applying 5% povidone iodine to the conjunctival cul de sac, preparing the periocular skin with 10% povidone iodine, careful sterile draping of the eyelid margins and eyelashes, adding antibiotics to the irrigating solution, instilling intracameral antibiotics at the close of surgery, injecting subconjunctival antibiotics, and applying topical antibiotic eyedrops after surgery.
Nonrandomized controlled trials and a prospective trial with the unoperated eye as the control have provided evidence that using topical 5% povidone iodine in the conjunctival cul de sac reduced the bacterial load and the incidence of postoperative infection.313-315 Lower concentrations of povidone iodine are less effective in reducing conjunctival bacterial colony counts.316The presence of lidocaine gel prior to povidone iodine instillation appears to diminish its antimicrobial efficacy.317
Systemic antibiotics are rarely used; however, it has been shown that certain oral fluoroquinolone antibiotics penetrate the blood/ocular barrier adequately to reach levels above the minimum inhibitory concentrations for many organisms inside the eye, and oral antibiotics that penetrate well into the eye may be beneficial.318-321
There is increasing evidence that supports the use of intraocular antibiotics to reduce the risk of endophthalmitis. The partially masked and randomized European Society of Cataract and Refractive Surgeons (ESCRS) study of the prophylactic effect of intracameral cefuroxime injection at the conclusion of the procedure and/or perioperative levofloxacin eyedrops on the incidence of endophthalmitis after phacoemulsification was halted early because of demonstration of a beneficial effect of intracameral cefuroxime. With data from 13,698 patients with complete follow-up records, investigators found that the odds ratio for developing endophthalmitis was 4.59 (95% CI, 1.74-12.08; P=0.002) in the group not receiving intracameral cefuroxime injection.300 The incidence of endophthalmitis in the control group was higher than that reported in some studies from U.S. centers. An earlier retrospective study in Sweden also reported efficacy of intracameral cefuroxime in reducing postcataract endophthalmitis, as did a later prospective, nonrandomized Swedish study that reported a similar endophthalmitis rate without cefuroxime and half the rate of endophthalmitis with intracameral cefuroxime.59,322 Five other retrospective studies in Europe have reported that intracameral injection of cefazolin or cefuroxime reduced postcataract endophthalmitis.51,299,323-326
One study used serial aqueous taps in cataract patients to determine that a single intracameral bolus of 1 mg of vancomycin achieved aqueous drug levels exceeding the minimum inhibitory concentration for most gram-positive bacteria for longer than 24 hours. Although efficacy has not been demonstrated, several studies support the safety of intracameral moxifloxacin injection for endophthalmitis prophylaxis.327-329
Mixing noncommercially formulated antibiotic solutions for intracameral use carries the risk of dilution errors with potential toxicity.330
In contrast to direct intracameral antibiotic injection, there are no corresponding studies to support the efficacy of placing antibiotics in the irrigation bottle, although this remains a common practice.331 Compared with an intracameral bolus, antibiotic in the infusate has the theoretical disadvantage of achieving less predictable intraocular antibiotic concentration and duration.57
Evidence of the benefit of injecting subconjunctival antibiotics at the conclusion of surgery is supported by two retrospective surveys. However, this is associated with risks that include intraocular toxicity from subconjunctival leakage through the incision with the potential for macular infarction when aminoglycosides are used.66,332,333
Retrospective studies suggest that topical antibiotic prophylaxis may be effective and a survey (1312 respondents; 33% response rate) from the American Society for Cataract and Refractive Surgery (ASCRS) members found that they were used by 88% of respondents preoperatively and 98% of respondents postoperatively.331 With respect to timing, other studies support the practice of initiating topical antibiotics immediately following surgery rather than waiting until the first postoperative day.61-65
Topical gatifloxacin and moxifloxacin have theoretical advantages of broad-spectrum coverage, bactericidal activity, and improved intraocular penetration, and they were the most frequent topical prophylactic antibiotics used by the ASCRS survey respondents.331 However, the higher cost of these drugs should be considered in light of the absence of any strong evidence of superiority over less expensive topical or intracameral antibiotics.334
In summary, major risk factors for endophthalmitis include older age, a leaky incision, and iatrogenic communication between the anterior and posterior segment (e.g., posterior capsular or zonular tears).
Use of a 5% solution of povidone iodine in the conjunctival cul de sac is recommended to prevent infection.314,335
There is mounting evidence that injecting intracameral antibiotics as a bolus at the conclusion of surgery is an efficacious method of endophthalmitis prophylaxis. The evidence supporting subconjunctival antibiotic prophylaxis is relatively weak. As an alternative to intracameral or subconjunctival injection, topical antibiotic instillation may be more protective when initiated on the day of surgery instead of on the first postoperative day. Because of the lack of and impracticality of sufficiently large prospective clinical trials, there is insufficient evidence to recommend a specific antibiotic drug or method of delivery for endophthalmitis prophylaxis.
In conclusion, the surgeon must ensure that antisepsis of the periocular surface, typically with povidone iodine, is achieved and that all incisions are closed in a watertight fashion at the end of the procedure65 It would appear that antibiotic use on the day of surgery is important rather than waiting until the next day. Any additional prophylactic antibiotic strategy in the perioperative period is up to the ophthalmologist to determine.
Toxic Anterior Segment Syndrome
Toxic anterior segment syndrome (TASS) is a sterile, postoperative, inflammatory reaction that typically presents within 12 to 48 hours following surgery and can mimic infectious endophthalmitis. Common clinical findings associated with TASS are diffuse "limbus-to-limbus" corneal edema and severe anterior chamber cell and flare, fibrin, and hypopyon. Sequelae may include an atonic pupil, secondary glaucoma, and corneal decompensation.336 Toxic anterior segment syndrome usually responds to anti-inflammatory medication, but permanent intraocular damage can occur. However, if there is sufficient suspicion of an infectious etiology, cultures of the anterior chamber and vitreous should be taken to rule out infection, and antibiotic treatment should be initiated.337
There is a large variety of factors that are associated with TASS, but it is often difficult to prove the etiology.336 Documented causes include heat-stable gram-negative endotoxin from municipal water supplies, use of chemical detergent and enzyme for cleaning of instruments, ointment seepage through clear corneal incisions, denatured ophthalmic viscosurgical device (OVD) residue, solutions of nonphysiologic pH and osmolality, and IOL polishing compounds. Dilution error resulting in a very high dose of intracameral antibiotic has also been documented as a cause of TASS.330
One published study reviewed 1276 TASS cases that were reported either by questionnaire (77 centers) or by site visit (54 centers) from 2005 to 2009.68 The most common factors associated with TASS were related to inadequate cleaning and sterilization of ophthalmic instruments: inadequate flushing of phacoemulsification and irrigation/aspiration handpieces and inappropriate use of enzymatic cleaners, detergents, and ultrasound baths for the cleaning and sterilization of instruments.68 A recent retrospective study of 26,408 consecutive cataract surgeries from a single institution during a 1-year period reported 60 cases of TASS, for an incidence of 0.22%. There were two identifiable clusters, but more than half of the cases were sporadic and unexplained. The visual outcomes were excellent, based on 6-month follow-up reported on 40% of the cases.67
Cataract Surgery Checklist
Protocols to minimize the incidence of preventable surgical errors regarding surgical site (e.g., wrong eye) and surgical procedure (e.g., wrong IOL implant) describe the steps to be taken before and on the day of surgery, and they delineate the roles and responsibilities for different members of the health care team.77-82 The Wrong-Site Wrong-IOL Checklist (see Appendix 3) is an example of how to document in the surgery chart that all the appropriate steps have been taken in preventing wrong-site and wrong-surgery events. Adherence to presurgical protocols or checklists has demonstrated a reduction in adverse surgery events and should be implemented.78,81
Beyond the skill set needed to perform the steps of the operation, cataract surgery also requires the cognitive skills, judgment, and experience necessary to recognize and respond to unexpected events, problems, and complications that may arise intraoperatively. Only an ophthalmologist has the medical and microsurgical training needed to perform cataract surgery.
The preferred method to remove a cataract is extracapsular extraction, most commonly by phacoemulsification. In the United States, the majority of cataract surgeries are performed by phacoemulsification. The 2010 Leaming Survey highlighted that many respondents use topical anesthesia with intracameral lidocaine, clear-corneal incisions, and a no-suture technique.338
In a randomized trial of ECCE and small-incision phacoemulsification, there were fewer surgical complications, visual acuity was significantly better, and there was a lower incidence of posterior capsular opacification (PCO) in the phacoemulsification group during the 1-year follow-up period.339
An adjunctive modality for cataract extraction is the femtosecond laser,340 which can be used to construct corneal incisions,341 perform the anterior capsulotomy, and fragment the nucleus. At present, there are few peer-reviewed studies that provide evidence on the relative benefits and disadvantages of femtosecond laser.
The ideal technical elements of a successful cataract procedure currently include the following:
- A secure, watertight incision that minimizes surgically induced astigmatism or reduces pre-existing corneal astigmatism342-345
- Thorough removal of all lens material346
- Minimal or no trauma to the corneal endothelium, iris, and other ocular tissues347,348
- Capsular bag fixation of an appropriate posterior chamber IOL
Intraocular steps that are commonly used during phacoemulsification include the following:
- Construction of an appropriately sized incision that is tight enough to achieve a fluidically stable anterior chamber349
- Use of an OVD to protect the corneal endothelium, manipulate tissues, and maintain adequate working space during surgery350
- Capsulorrhexis,351 which is a continuous curvilinear capsulotomy that facilitates hydrodissection, prevents posterior capsule tears that originate from radial anterior capsule tears, and facilitates the implantation, fixation, and centration of the IOL within the capsular bag. A capsulorrhexis that completely overlaps the IOL edge impedes the development of PCO for some IOL designs.352
- Hydrodissection,353 which reduces zonular stress during phacoemulsification by mobilizing the nucleus and epinucleus. By facilitating thorough cortical aspiration, hydrodissection also helps to retard PCO.354,355
- Nuclear disassembly and emulsification using techniques such as divide and conquer356 or chopping357 to allow nuclear removal through a capsulorrhexis and small incision358
- Thorough removal of remaining epinucleus and cortex346
- Implantation and centration of a small-incision IOL within the capsular bag, or as dictated by capsular anatomy, secure fixation of the IOL in the ciliary sulcus69 (with or without sutures or capsulorrhexis capture359) or anterior chamber
- Removal of the OVD to minimize postoperative IOP elevation360
- Assurance of a watertight incision using sutures if the incision size and architecture alone do not produce a secure, self-sealing wound59,286,342,361,362
Incision location, size, and design may depend on several factors, including the patient's orbital anatomy, the type of IOL to be implanted, the role of the incision in astigmatism management, and surgeon preference and experience. For example, varying the incision characteristics and centering it on the steep corneal meridian may reduce pre-existing astigmatism.363-365
When feasible, small-incision surgery is generally preferred for a number of reasons.366 Smaller incisions are amenable to self-sealing wound construction so that fewer or no sutures are needed for secure closure. They are therefore inherently safer in the event of sudden patient movement or a suprachoroidal hemorrhage during surgery, and there are fewer physical restrictions postoperatively. They may be associated with less initial postoperative inflammation.367,368 Finally, smaller incisions induce less unwanted astigmatic change than larger incisions366,369-373 and result in earlier and greater long-term stability of the refraction.374-376
Large-incision manual ECCE may be preferred for certain complicated eyes, such as those with mature nuclei, weak zonules, or a higher risk of corneal decompensation.
Intraocular lens implantation is the method of choice to correct aphakia, unless there are specific contraindications.377 Posterior chamber IOL implantation in the capsular bag is the optimal method in most cases.378
Cataract surgeons can choose from a wide variety of posterior chamber IOL styles and materials to find the appropriate one for their patients' needs. Intraocular lens optic size and shape, optic and haptic configuration, optic edge design,379-382 optic and haptic materials,383-385and chromophore content are engineered to give a variety of characteristics.
Rigid polymethyl methacrylate (PMMA) posterior chamber IOLs were most frequently used before foldable IOLs. Foldable IOLs are now the most common choice following phacoemulsification because of their ability to be implanted through smaller incisions. Foldable IOLs can be classified according to their optic material: silicone; hydrophilic acrylic, hydrophobic acrylic; and collagen/hydroxy ethyl methacrylate [HEMA]-copolymer-based. Almost all IOLs have ultraviolet-blocking chromophores. Glistenings are fluid-filled microvacuoles that form within the IOL optic when the IOL is in an aqueous environment. They are observed in all types of IOLs but have been mainly associated with some hydrophobic acrylic IOLs. Although the impact of glistenings on postoperative visual function and the evolution of glistenings in the late postoperative period remain controversial, IOL explantation has rarely been reported.386 Each IOL is associated with unique positive and negative attributes with regard to material, design, and insertion system. It is therefore incumbent upon each surgeon to have an understanding of the various attributes of each IOL.
When combined with a sharp posterior optic-edge and an overlapping capsulorrhexis, silicone and hydrophobic acrylic foldable IOLs are associated with a low incidence of PCO. All foldable IOL materials are associated with minimal giant-cell foreign-body reaction.387-389 Foldable IOLs can be inserted with either forceps or with injection devices; in some cases IOLs come preloaded in insertion devices.390,391Insertion devices facilitate consistently reproducible insertion through small incisions while preventing any contact of the lens with debris or microorganisms residing on the patient's ocular surface.305
Noncapsular-bag IOL fixation may at times be necessary due to zonular abnormalities or anterior or posterior capsular tears. The surgeon should have backup IOLs available as a contingency. Options include implanting either an anterior chamber IOL or a posterior chamber IOL positioned in the ciliary sulcus.69,392-395 Suturing of posterior chamber IOL haptics to the iris or sclera may be necessary in the absence of sufficient residual capsular support.69,392-395 Certain IOL designs, such as accommodating or plate haptic IOLs, require capsular-bag fixation. In general, single-piece acrylic IOLs should not be implanted in the ciliary sulcus because of associated risks such as IOL decentration and posterior iris chafing that cause transillumination defects, pigment dispersion, elevated IOP, recurrent hyphema, and inflammation.69
Optimal characteristics of a sulcus-fixated posterior chamber IOL include sufficient overall length, posterior haptic angulation, and the absence of sharp anterior optic edges.69 With no posterior capsular barrier, silicone IOLs may compromise surgical visibility should silicone oil or expansile gas ever be required.70,71 Anticipating a more anterior location of the optic, the sulcus IOL power should be decreased by 0.5 diopters (D) to 1.0 D relative to that calculated for capsular-bag fixation (but decreased less with capsulorrhexis capture of the optic).72,73 The latter strategy reduces reliance on adequate haptic length to provide optic centration and stability.74 Because noncapsular bag fixation may increase the potential for optic tilt and decentration, the surgeon should reconsider whether multifocal IOLs or IOLs with higher degrees of negative spherical aberration should be implanted.75,76
Suture fixation of one or both haptics of a posterior chamber IOL to the iris or sclera is an option in the absence of sufficient capsular support.69,392-395 Risks of these approaches include improper anatomic placement and suture breakage.396-400 Effective use of an anterior chamber IOL depends on appropriate IOL design, sizing, and proper placement. Iris deformity, pupil distortion, and physical discomfort may result from an IOL that is too long, while rotation and movement of an IOL that is too short may induce chronic inflammation, cystoid macular edema (CME), and corneal endothelial damage.69 A peripheral iridectomy should be used to prevent the risk of pupillary block associated with an anterior chamber IOL. Multiple studies support the efficacy of all three methods of IOL fixation-anterior chamber and iris or scleral sutured posterior chamber-in the absence of adequate capsular support.69,392-395
Optical and Refractive Considerations
Spherical IOLs, in which marginal light rays are focused proximally relative to paraxial light rays, have positive spherical aberration.
Aspheric IOLs have been designed to reduce or eliminate the spherical aberration of the eye. Multiple clinical studies have demonstrated a pupil-dependent reduction in ocular spherical aberration with aspheric IOLs, and some of these studies have also revealed varying degrees of superior contrast sensitivity with these IOLs relative to spherical IOLs.46,401-413However, the potential advantages of aspheric IOLs remain controversial, particularly in the areas of functional benefit414-416 and depth of focus.188,417 The potential advantages and disadvantages can be affected by pupil size,418 IOL tilt419 and decentration,75 and whether the spherical aberration of the IOL and the patient's cornea were custom matched.420,421
Toric IOLs reduce eyeglass dependence after cataract surgery due to corneal astigmatism. Between 15% and 29% of cataract patients have more than 1.5 D of keratometric astigmatism.422,423 Toric IOLs have been shown to decrease eyeglass dependence compared with nontoric monofocal IOLs.424,425 In addition, they may offer better predictability and stability of correction compared with incisional astigmatic keratotomy.426,427 For a toric IOL to be effective, the axis and magnitude of keratometric astigmatism must be accurately measured, and the IOL must be accurately and permanently aligned.428 Toric IOL axis misalignment may reduce the desired refractive effect or may even worsen the overall astigmatism. Because toric IOLs do not correct irregular astigmatism, they should not be used in patients who will require a rigid contact lens.
Monovision- and presbyopia-correcting IOL implants are used in an attempt to improve quality of life by reducing eyeglass dependence after cataract surgery.429 For each of these options, patient selection is critical, because certain patient-related factors may be associated with suboptimal postoperative performance and reduced patient satisfaction. Surgeons must understand the individual patient's lifestyle and expectations so that the best IOL option can be selected. Patients should be informed of the potential compromise in quality of vision associated with these choices.430,431
Monovision is a condition in which one eye is corrected for distance vision and the fellow eye is corrected for intermediate or near vision. The success of monovision depends on interocular blur suppression where the blurred image from one eye does not interfere with the image from the in-focus eye. In one study, when the dominant eye was corrected for distance visual acuity, the overall monovision acceptance rate following cataract and IOL surgery was 90% in a cataract population that desired independence of correction with eyeglasses.432 In a small, nonrandomized study comparing patients who had bilateral multifocal IOLs versus bilateral monofocal IOLs implanted to achieve monovision, there was no statistical difference in bilateral uncorrected distance and near vision, or in the satisfaction scores.433 Patients with a history of monovision success are particularly well suited for this modality.434,435
Presbyopia-correcting IOLs can be classified as multifocal or accommodative (the lens changes position or shape within the eye).
Multifocal IOLs achieve their effect by dividing incoming light into two or more focal points and can be classified as refractive or diffractive. A Cochrane systematic review concluded that multifocal IOLs were effective at improving near vision when compared with monofocal IOLs and that unaided distance visual acuity was similar in the two groups.436 Optical effects of multifocal IOLs may include reduced contrast sensitivity, halos around point sources of light, and glare.437 Whether the improvement in near unaided acuity outweighs the optical side effects of multifocal IOLs will vary among patients, with important factors being the motivation to achieve eyeglass independence and adaptation over time.438 Patient selection and counseling are particularly important with these IOLs. There may be a symptomatic reduction in the quality of distance vision, particularly if other ocular pathology is present. Therefore, the candidacy of patients with amblyopia or abnormalities of the cornea, optic disc, and macula for a multifocal IOL must be carefully considered.
In an attempt to mimic human accommodation, accommodative presbyopia-correcting IOLs are designed to change position or shape in the eye with accommodative effort. These IOLs have demonstrated varied accommodative potential without the loss of contrast sensitivity inherent with multifocal IOLs.439,440
Results of multiple large studies of cataract surgery have repeatedly demonstrated positive outcomes. The ASCRS National Cataract Database reported that at 3 months postoperatively 85.5% of all patients had a 20/40 or better BCVA, 57.2% of patients had 20/25 or better postoperative BCVA, and 74.6% of patients were within ±1.0 D of target spherical equivalent. Based on 5788 responses, the mean visual function index score at 3 months postoperatively was 70.3% compared with 55.0% preoperatively. (The score is based on a scale of 0 to 100, with 0 indicating an inability to perform any of the activities.) The European Cataract Outcome Study for 1999 reported that 89% of patients achieved a postoperative visual acuity of 0.5 or more (20/40 or better), the average induced astigmatism was 0.59 D, and 86% of patients had an induced astigmatism within ±1.0 D.441 This study was conducted in 14 countries with up to 40 participating surgeons during the years 1995 to 1999, and it collected operative and follow-up information on a total of 8646 patients, including 3033 patients in 1999.
The American Academy of Ophthalmology National Eyecare Outcomes Network (NEON) database (n=7626) also found similar rates of success, with an improvement in visual acuity in 92.2% of patients and improvement in VF-14 in over 90% of patients.442 Best-corrected visual acuity of 20/40 or better was achieved by 89% of all NEON patients and by 96% of NEON patients who lacked preoperative ocular comorbid conditions.442 Seventy-eight percent of patients were within ±1.0 D of target spherical equivalent. Ninety-five percent of patients reported being satisfied with the results of their surgery. Patients who were dissatisfied with the results of their surgery were slightly older and more likely to have ocular comorbidity. More recently, a large multicenter study in the United Kingdom showed results from cataract surgery of 20/40 or better in 94.7% of eyes with no ocular comorbidity.443
In studies of phacoemulsification cataract surgery performed by ophthalmology residents, the reported range of patients with postoperative BCVA of 20/40 or better was 80% to 91%.444-449 If eyes with ocular comorbidities are excluded, the reported range of patients with postoperative BCVA of 20/40 or better was 86% to 98%.447-450
The Cataract Patient Outcomes Research Team (PORT) study identified preoperative characteristics that were independent predictors of greater improvement after surgery: younger age, less comorbidity, higher cataract symptom score, and worse preoperative VF-14 (measure of visual function) score.30 These investigators found that patients younger than 65 showed greater improvement than those over 65 and that patients with more severe symptoms and more severe dysfunction showed greater improvement than those with less severe symptoms or dysfunction.30 Preoperative Snellen visual acuity was found to be unrelated to the likelihood of improvement in symptoms or self-reported visual function after cataract surgery in several studies.30,451,452 In another study, a prospectively validated model found that predictors of improvement included younger age, a poorer preoperative visual function as measured by the ADVS, and absence of diabetes.451 Even patients with diabetes and age-related macular degeneration (AMD), however, showed significant improvements after cataract surgery, albeit at a lower magnitude than patients without these conditions.453-455 Although these studies have shown that benefits are greater in patients of younger age, the improvement in quality of life for those 75 years old and older is still functionally and statistically significant.
Another study used a validated visual function questionnaire and a variety of psychophysical methods to assess visual improvement in patients with symptomatic cataracts but preoperative Snellen acuity better than or equal to 20/50.29 Even in eyes with 20/20 preoperative Snellen acuity, cataract surgery improved patients' self-reported visual impairment. Neither the preoperative best corrected high-contrast Snellen distance acuity nor the change in Snellen acuity predicted the observed improvement in visual function as reflected in the pre- and postoperative questionnaire scores. The strongest preoperative indicators for improved visual function were glare disability tested at low and medium spatial frequencies and the visual function questionnaire score. This suggests that in patients with symptomatic nonadvanced cataract, Snellen acuity in isolation will not accurately predict who will benefit from surgery.
Complications of Cataract Surgery
Although there are numerous complications that can occur after cataract surgery, those resulting in permanent loss of vision are rare. Major complications that are potentially sight-threatening include infectious endophthalmitis, TASS, intraoperative suprachoroidal hemorrhage, CME, retinal detachment, persistent corneal edema, and IOL dislocation.
The Cataract PORT reviewed the incidence of cataract complications from studies published prior to 1992 and with an overall phacoemulsification/manual ECCE case mix of 2:1456 Six subsequent studies of adverse perioperative outcomes from cataract surgery are summarized in Table 2. Greenberg et al457 reviewed the incidence of complications from cataract surgeries performed at the U.S. Veterans Health Administration system from 2005 to 2007. The most common ocular complications were posterior capsular tear, anterior vitrectomy, or both during surgery (3.5%), and PCO after surgery (4.2%). The rate of CME was 3.3% and the rate of retained lens fragments was 1.7%.
TABLE 2. Complication Rates from Selected Studies of Cataract Surgery (PDF 212k)
Stein et al458 stratified Medicare beneficiaries who underwent cataract surgery into three cohorts: those who had their first cataract surgery in 1994-1995 (n=57,780), 1999-2000 (n=73,064), or 2005-2006 (n=90,750). The overall rate of severe complications in the 1-year postoperative period was 0.5%; severe complications were defined as endophthalmitis (0.16%), suprachoroidal hemorrhage (0.06%), and retinal detachment (0.26%). The probability of a severe complication declined over time from 0.6% in the earliest cohort to 0.4% in the most recent group.
A study performed in the United Kingdom reported the overall rate of complications after phacoemulsification as 8.7%.459 Of the complications reported, 2.4% were considered major, including vitreous loss (1.1%), lens drop (0.1%), iris trauma (1.2%), retinal detachment (0.2%), and endophthalmitis (0.1%). Other nonmajor complications included wound leak (1.1%), prolonged corneal edema (0.7%), uveitis (1.1%), and persistent elevated IOP (0.3%).
Specific complications following cataract surgery are discussed below.
An incision that is not watertight can lead to several complications, including postoperative wound leak, hypotony, and endophthalmitis.65 An incision that is too small can decrease the ability to cool the ultrasonic phacoemulsification needle and increase the risk of wound burn. An incision that is too large will cause leakage of fluid from the wound and destabilize the anterior chamber. Wound burn (ultrasound stromal thermal damage) occurs at 60º C or higher.462 A recent survey representing 419 cases of wound burn, showed anincidence of 0.043%.463 In a multivariate analysis, the factors significantly associated with this problem in order of decreasing significance were lower surgical volume, the surgical technique, and the OVD used.463
An incision that is not self-sealing at the end of the surgery may require sutures or adhesive for proper closure. The risk of perioperative wound leak (e.g., risk increased with eye rubbing, poor scleral rigidity) is another consideration for the use of sutures or eye protection postoperatively. Sutures can induce postoperative astigmatism, the magnitude of which is dependent on their location and tension.365,464
Iris prolapse can result from intraoperative floppy iris syndrome (IFIS) or a poorly constructed incision. Other causes of surgical iris trauma may include iris aspiration or agitation with the phacoemulsification tip, sphincterotomies, and excessive stretching or manipulation with expansion devices and instruments. The sequelae of such trauma may include iridodialysis, hyphema, transillumination defects, traumatic mydriasis, and an irregular, atonic, or misshapen pupil. Sphincter necrosis can occur perioperatively as a result of endophthalmitis, TASS, or excessive IOP elevation.
Improper instrument entry into the anterior chamber can lead to Descemet's membrane tears or detachment.465 A small tear can be repaired by repositioning and tamponading the flap of Descemet's membrane with an air bubble. The corneal endothelium is susceptible to damage from any mechanical injury and from prolonged ultrasonic power during nuclear removal. It can also be damaged by intraocular solutions with a nonphysiologic osmolarity or pH, or by chemical insult from toxic contaminants or improperly formulated intraocular solutions and medications.68,336 Prolonged elevated IOP can lead to further endothelial decompensation and corneal edema.
There are several etiologies for abnormally prolonged postsurgical inflammation. Persistent iritis has been associated with retained lens fragments,466 history of uveitis,467 and a subacute infection with Propionibacterium acnes.468 Insufficient administration of postoperative anti-inflammatory medication may also be a contributory cause.
In studies of cataract surgery in the United States, the reported incidence rates of postoperative endophthalmitis are 0.04% to 0.2%.4,279,291,457 The incidence of endophthalmitis reported in other English-language peer-reviewed literature ranges from 0.02% to 1.16%.60,296,298,321,442,456,458,460,469-472 Staphylococcus epidermidis was the most common pathogen.469,470 Risk factors for developing endophthalmitis after cataract surgery include posterior capsular rupture (up to 10-fold increase),65,66,291,296,472 older age,296 relative immunodeficiency,291 resident-performed cataract surgery,66 wound leak on first postoperative day,65 inferior incision location,291 longer length of surgery,473 topical anesthesia,473 and the use of topical lidocaine gel before povidone iodine.291
The type and size of incision (clear corneal or sclera) has been implicated as a possible factor in the development of endophthalmitis. Several articles found no conclusive evidence for an association of clear corneal incision and endophthalmitis.291,474,475
Patients may present with complaints of decreased vision, pain, redness, new floaters, and eyelid edema.476,477 Although historically the onset of symptoms was considered to occur during the first postoperative week,49,478,479 newer studies report a delayed onset of up to 13 days.291,480 Common findings include conjunctival injection, corneal edema, anterior chamber inflammation, hypopyon, and vitritis.476,477
If endophthalmitis is suspected, referral to a retina specialist is appropriate. If a retina specialist is not available within 24 hours, the anterior or posterior chamber should be tapped for evaluation of possible pathogens, followed by an intravitreal injection of antibiotics. The Endophthalmitis Vitrectomy Study (EVS) recommended an intravitreal tap plus injection of antibiotics alone in patients who presented with vision of hand motion or better. Conversely, patients who presented with vision of light perception or worse were more successfully treated with a pars plana vitrectomy and antibiotics.49
Posterior Capsular Tear or Zonular Rupture
There is great variability in reported rates of posterior capsular or zonular ruptures. They range from 1.6% up to 9% in high-risk patients with previous pars plana vitrectomy.442,443,481-483 Risk factors for posterior capsular tears and vitreous loss include older age, male gender, glaucoma, diabetic retinopathy, brunescent or white cataract, inability to visualize the posterior segment preoperatively, pseudoexfoliation (exfoliation syndrome), small pupils, axial length greater than 26 mm, use of systemic sympathetic alpha-1a antagonist medication, previous trauma, inability of the patient to lie flat, and resident-performed cataract surgery.484,485 Intraoperative risk factors include loose zonules, need for capsular stain, and miosis.485
The factors listed above are the known risk factors. However, posterior capsular and zonular complications can sometimes occur without any obvious predisposing factors. A discussion with the patient about possible complications and difficulty in assessing risk before cataract surgery may be beneficial.
Retained Lens Fragments
The incidence of retained lens fragments is 0.18% to 0.28%.443,456 If there is vitreous loss with posteriorly dislocated lens fragments, it is recommended that the surgeon perform an anterior vitrectomy, with stable placement of an appropriately sized and designed IOL, if available.
The use of injected triamcinolone has been reported to aid in visualization of residual vitreous.486 One study found that a large number of IOLs placed during primary surgery complicated by vitreous loss required subsequent explantation. If the appropriate backup IOL power, size, or design is not available, then consideration should be given to leaving the eye aphakic at the time of the primary surgery.487 Because of the increased risk of inflammation and elevated IOP, strong consideration should be given to referring patients who have retained lens fragments to a retina surgeon during the early postoperative period.488
The most appropriate timing of the secondary pars plana vitrectomy is unclear, but the eye should be carefully monitored for complications, such as elevated IOP and inflammation, as long as retained nuclear fragments are present.489-491
Overall rates of retinal detachment range from 0.26% to 4.0%.458,460,475,492-497 Risk factors for development of retinal detachment after cataract surgery included axial length more than 23 mm, posterior capsular tear, younger age, male gender, lattice degeneration, zonular dehiscence, retinal detachment in the fellow eye, and postoperative posterior vitreous detachment.475,492-497 In one study, the mean interval between cataract surgery and retinal detachment was 39 months,497 but the increased risk of retinal detachment in pseudophakic eyes may continue for as long as 20 years.498 In a single-surgeon prospective case series of 22 years' duration, the risk of retinal detachment after phacoemulsification for female patients with axial length less than 24 mm and age 60 or younger was zero.499 There was no statistically significant difference in the probability of retinal detachment after ECCE compared with phacoemulsification.498
Historically, the incidence of suprachoroidal hemorrhage related to large incision cataract surgery was reported to be 0.15% to 0.19%500 and associated with myopia, glaucoma, diabetes, atherosclerotic vascular diseases, and hypertension.501 Published data on the incidence of this complication following phacoemulsification are lacking. Anticoagulation with warfarin does not significantly increase the risk of choroidal hemorrhage.502
Clinical signs and symptoms of an intraoperative choroidal hemorrhage include pain, dark shadowing and loss of red reflex, elevated IOP, shallowing of the anterior chamber, and iris prolapse.503 Failure to diagnose the hemorrhage and secure the incision can lead to sight-threatening complications.
Cystoid Macular Edema
Clinically significant CME occurs infrequently after routine uncomplicated small-incision cataract surgery (1.2% to 3.3%)443,457,459 and often responds well to medical therapy; however, recalcitrant cases may be associated with permanent impairment of central visual acuity. Risk factors for CME include previous uveitis, posterior capsule rupture with vitreous loss, retained lens material, diabetic retinopathy, epiretinal membrane, prior vitreoretinal surgery, nanophthalmos, retinitis pigmentosa, and a history of pseudophakic CME in the fellow eye. Anatomic diagnosis is frequently made by OCT, which is less invasive than fluorescein angiography. Snellen visual acuity may underestimate the impact of CME on visual function.
Because CME is generally associated with postsurgical inflammation, topical anti-inflammatory medications are used to prevent and to treat established CME. There is evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) alone or in combination with corticosteroids are more effective than topical corticosteroids alone in preventing and treating acute and chronic CME.504-516 The use of intravitreal antiangiogenesis agents for treatment of CME is being investigated, but there is insufficient evidence to support their use at this time.517
At present, there is no firmly established protocol for preventing postsurgical CME. Although perioperative prophylactic use of NSAIDs for prevention of CME has been advocated for high-risk eyes based on a number of studies, there is no published evidence that the final visual outcome is improved with routine use of prophylactic NSAID.
There is a recognized tendency for transient elevation of IOP in many eyes during the early postoperative period. Although this rarely causes serious complications, acute postoperative IOP elevation can induce pain, and some eyes may be more susceptible to optic nerve damage or vascular occlusion. The likelihood for IOP elevation increases if excess amounts of the OVD remain in the eye at the close of surgery, and thorough removal of OVD should be attempted.518 The optimal pharmacological regimen for preventing an immediate postoperative IOP spike is unclear. It appears that topical aqueous suppressants and intracameral carbachol are most beneficial.519-537
Topical corticosteroid use can cause elevated IOP in eyes that are "steroid responders."538 This is more likely to occur in patients who are younger, highly myopic, or have glaucoma.539 Corticosteroid cessation results in a reduction of the IOP to normal levels, and the IOP should therefore be monitored in eyes being treated with postoperative corticosteroid medication.538
Complications of Intraocular Lenses
Complications specific to the IOL occur infrequently but vary depending on the design and material of the particular IOL. In the ASCRS/ESCRS registry of IOL explants, the most common reasons for explantation of foldable IOLs are dislocation or decentration, glare or optical aberrations, incorrect power, and opacification540 The incidence of multifocal IOL explants secondary to glare/optical aberrations is increasing (Mamalis N, Davis D, Maddula S, Ness P. ASCRS/ESCRS survey on foldable IOLs requiring explantation or secondary intervention: 2009 update. Poster presented at: ASCRS Symposium on Cataract, IOL, and Refractive Surgery, April 10, 2010; Boston, MA). Although uncommon, explantation of multifocal IOLs may become necessary if optical side effects are intolerable. Intraocular lenses may also be damaged during implantation, and it may be necessary for the surgeon to consider intraoperative lens implant exchange.
Posterior chamber IOL decentration can result from damaged haptics, zonular dialysis, anterior or posterior capsular tears, asymmetric capsulorrhexis, asymmetric capsular contraction and fibrosis, and asymmetric placement of the IOL haptics with one haptic in the ciliary sulcus and the other inside the capsular bag. A malpositioned posterior chamber IOL can cause significant visual complaints such as edge glare, higher order aberrations, or IOL inflammation associated with uveal irritation such as iris chafing541
Dislocation/decentration has been reported with virtually all IOL materials and models, including both one- and three-piece designs540 This complication is seen most commonly when IOLs are not placed symmetrically within the capsular bag or when there is a situation in which the IOL is placed without an intact capsulorrhexis. The major predisposing factors found for IOL subluxation in one study were secondary implantation, posterior capsular rupture, and mature cataracts.542 Plate haptic silicone IOLs can dislocate posteriorly following Nd:YAG capsulotomy and, rarely, spontaneously from capsular contraction. Delayed in-the-bag spontaneous posterior IOL dislocation is associated with zonular insufficiency, such as with pseudoexfoliation (exfoliation syndrome), prior vitreoretinal surgery, or a history of trauma.543-545 The onset is delayed and occurred on an average of 8.5 years following uncomplicated cataract surgery in a study of 86 consecutive cases.545 Spontaneous bag-IOL dislocation can occur with all IOL materials including PMMA, silicone, and hydrophobic acrylic, as well as with both one-piece and three-piece IOL designs545
Glare or optical aberrations are another common reason for explantation. The term dysphotopsia has been used to describe a variety of unwanted visual phenomena encountered by pseudophakic patients.546,547 Positive dysphotopsias may include halos, ghost images, starbursts, and arcs, rings, or flashes of light that may ultimately interfere with visual function. The most common negative dysphotopsia is manifest as a dark crescent or curved shadow that can appear similar to a scotoma in the peripheral temporal field of vision.548-550 Initially, positive and negative dysphotopsias were most commonly reported with high refractive-index hydrophobic acrylic IOLs with reflective square edges. However, they have since been reported with many different IOL materials and designs, including silicone and hydrophilic acrylic IOLs.380,551-554 Certain optic design characteristics such as a square peripheral edge, flat anterior surface, smaller optic diameter, and multifocality are more likely to result in unwanted optical images.548,552,555,556 Complications such as IOL opacification, cracked or damaged optics, and IOL decentration frequently cause dysphotopsias as well. Implantation of a piggyback IOL or reverse optic capture (placing the optic anterior to the capsulorrhexis) appears to reduce the symptoms of negative dysphotopsia. It appears that negative dysphotopsia may be induced at the interface of the capsulorhexis and the anterior surface of the IOL, suggesting that a reflection of the anterior capsulotomy edge is projected onto the nasal peripheral retina.557
Incorrect IOL power may also lead to explantation. It is not possible to predict precisely the final axial position of an implanted IOL. An unwanted refractive result or "surprise" is therefore an inevitable outcome in some patients. The risk is greater with inaccurate keratometry or axial length measurements, such as with uncooperative patients, postrefractive surgery eyes, and atypical anatomic variations such as a staphyloma (see sections on biometry and cataract surgery following prior keratorefractive surgery). Incorrect IOL labeling or mistakenly implanting the wrong IOL may result in an unwanted refractive surprise. Finally, surgical factors that can affect the effective lens position include retained OVD in the bag, improper haptic or optic placement, capsulorrhexis diameter, and inversion of the IOL.
When an unacceptable or intolerable refractive error results following IOL implantation, the risks of surgical intervention must be weighed against the alternatives of eyeglass or contact lens correction. Surgical alternatives to IOL exchange include keratorefractive surgery and secondary ciliary sulcus implantation of a piggyback IOL.
The incidence of IOL opacification or calcification appears to be decreasing according to more recent surveys of IOL explantation.540 While IOL calcification was reported with earlier hydrophilic acrylic IOLs, newer hydrophilic acrylic IOLs have been widely used in Europe without a significant incidence of calcification.558-562 Opacification of hydrophilic acrylic IOLs may be misdiagnosed as an opacity of the lens capsule or vitreous, leading to unnecessary surgical intervention.563 More recently, opacification of silicone IOL optics due to calcium deposits following Nd:YAG capsulotomy in eyes with asteroid hyalosis has been reported.564,565 For this reason, it may be prudent to avoid silicone IOLs in these patients.
The complication of interpseudophakic opacification can occur when lens epithelial cells migrate in between the optics of two piggybacked IOLs (especially two hydrophobic acrylic IOLs) that have both been implanted within the capsular bag.256,257This dense fibrocellular material is difficult to remove and may require explantation of both IOLs.
This problem has not been reported when a silicone piggyback IOL has been implanted in the ciliary sulcus following bag placement of the first IOL, unlike when both IOLs are placed within the capsular bag.
As noted earlier, implantation of single-piece acrylic IOLs in the ciliary sulcus are associated with pigment dispersion, iris transillumination defects, elevated IOP, and recurrent inflammation or hemorrhage. Malpositioned anterior chamber IOLs may result from improper sizing, iris tuck following implantation, or rotation of a haptic through a peripheral iridectomy. Excessive anterior chamber IOL mobility can lead to corneal endothelial decompensation.
Preoperative ocular comorbidities may have a significant effect on the outcome of cataract surgery.4,451,566 Many comorbid conditions are associated with the potential for reduced improvement in visual function or BCVA,567 and the patient should be adequately informed and counseled during the care process. This is particularly true if the patient is electing to receive a refractive- or presbyopia-correcting IOL. Comorbid conditions found in patients with cataracts and the special considerations associated with these conditions are listed in Table 3.
TABLE 3. Selected Ocular Comorbidities (PDF 86k)
The presence and extent of AMD may be defined preoperatively through the use of diagnostic instrumentation such as OCT, fluorescein angiography, and potential acuity instruments, which can assist in establishing realistic expectations. There is increasing evidence that the risk for worsening of pre-existing AMD following cataract surgery is low.568,569
The status of coexisting diabetic retinopathy, particularly macular edema, may be evaluated by OCT, thereby directing a more vigorous approach to preoperative, intraoperative, and postoperative medical treatment, including the use of intravitreal injections.570-574 Historically, cataract surgery was considered to increase the risk of progression of diabetic retinopathy postoperatively.575 Cataract surgery appears to increase the risk of progression of certain types of diabetic retinopathy postoperatively (e.g., from moderate nonproliferative to severe nonproliferative diabetic retinopathy). However, cataract surgery does not appear to increase the risk of progression of adequately treated proliferative diabetic retinopathy or macular edema.576 Nevertheless, the visual prognosis for these patients is still uncertain and may be guarded.576,577
Because of the risk of corneal decompensation in the presence of corneal endotheliopathy, the surgeon may consider using retentive OVDs and machine parameters and surgical techniques that reduce cumulative ultrasound time and endothelial trauma.578,579
Pseudoexfoliation (exfoliation syndrome) is commonly associated with a small pupil and weak zonules, which increases the risk of capsular rupture and retained nuclear fragments.580 Anterior chamber depth should be assessed preoperatively; an anterior chamber depth of less than 2.5 mm, indicative of zonular weakness, increases the risk of complications fivefold.581
Because of the risk of late bag-IOL dislocation, Nd:YAG anterior capsule relaxing incisions may be considered for anterior capsule contraction.
The optimal timing of cataract surgery in the presence of uveitis is a function of many factors. Inflammation should be inactive or at its best level of control prior to elective surgery.605 Anti-inflammatory medications are often begun prior to surgery, and they are then used more frequently and for longer durations following surgery. Intravitreal, periocular, or systemic administration of anti-inflammatory medication may also be considered606
In addition to ocular comorbidities, other characteristics of the patient or eye may be associated with a higher risk for intraoperative and postoperative complications. High-risk characteristics include a history of previous eye surgery, special types of cataracts, very large and very small eyes, deeply set eyes, small pupils or posterior synechiae, scarred or cloudy corneas, weak or absent zonules, prior ocular trauma, and the systemic use of alpha-1a antagonists. Each set of circumstances poses unique challenges (see Table 4). As with ocular comorbidities, patients with high-risk characteristics should be informed about the specific impact of their condition on the expected course and outcome of surgery, along with options that may be considered in the event that complications occur.
TABLE 4. High-Risk Characteristics for Intraoperative and Postoperative Complications (PDF 120k)
In handling high-risk eyes, several technique modifications and/or adjunctive devices should be considered.
Ophthalmic viscosurgical devices vary in rheologic properties that may be advantageous for certain higher risk cases.607 A specific OVD may be selected based on its characteristics in cases of corneal endothelial deficiency, shallow anterior chamber, intumescent cataract, and small pupil.607
Capsular dyes to stain the anterior capsule may be considered in cases of a white or mature cataract, or where visibility is compromised.608,609
Capsular tension rings can be useful adjunctive devices when weak zonules are present, reducing the likelihood of intraoperative zonular separation and capsular complication,610and they may improve postoperative IOL centration.611 In cases of more profound zonulopathy, other options include capsular retractors, a modified capsular tension ring, or capsular tension segment should be considered for scleral suture fixation.612
A variety of intraoperative methods have been described to expand the small pupil. Pharmacologic methods include intracameral alpha-1 agonists such as epinephrine or phenylephrine. Mechanical methods include viscomydriasis, release of posterior synechiae, pupil stretching, or microsphincterotomies, iris retractors, or pupil expansion rings.613
Intraoperative floppy iris syndrome is a unique small-pupil syndrome that may be associated with iris billowing and prolapse as well as with progressive intraoperative miosis.35,36 It is associated with a higher rate of surgical complications, particularly when it is not recognized or anticipated.35-39 Pupil stretching and sphincterotomies are ineffective in these eyes, and pharmacologic approaches, viscomydriasis, and pupil-expansion devices, either alone or in combination, should be used to manage IFIS.35-37
Systemic comorbidities that may be of importance intraoperatively are diabetes mellitus, pulmonary dysfunction, cardiovascular dysfunction (e.g., poorly controlled blood pressure, poorly controlled heart failure), musculoskeletal disorders causing positional difficulties, tremor, severe hearing impairment, anxiety disorders, mental retardation, dementia, and coagulopathies.614,615 The occurrence of IFIS is strongly associated with systemic alpha-1 antagonists, whose most common indication is the symptomatic treatment of benign prostatic hyperplasia.35,36 The American Urological Association guidelines for the management of benign prostatic hyperplasia recommend that men with planned cataract surgery avoid the initiation of alpha-1 antagonists until their cataract surgery is completed.616 Discontinuing alpha-1 antagonists preoperatively does not typically prevent IFIS, which may occur long after drug cessation.35-38,616 Several retrospective and prospective studies35,36,38,39,617 suggest that IFIS is more frequent and severe in patients taking the alpha-1A subtype specific antagonist, tamsulosin, than in patients taking nonselective alpha-1 antagonists, and this has been confirmed in a meta-analysis.40
For patients with complex medical conditions, it may be beneficial to coordinate care with the patient's primary care physician. Depending on the planned anesthesia and sedation, appropriate measures should be taken to stabilize and monitor the condition.
There is insufficient evidence to recommend continuation or discontinuation of anticoagulant or antiplatelet therapy for cataract surgery.618,619 Discontinuation of these medications can be associated with medical morbidity. In patients with new coronary stents, premature discontinuation of dual antiplatelet therapy is associated with an increased risk of life-threatening stent thrombosis.620 In a study of 19,283 eyes, the incidence of adverse medical and ophthalmic events was low and statistically indistinguishable in patients who either continued or discontinued anticoagulant or antiplatelet medication use before cataract surgery.621 Several uncontrolled case series reported minimal or no complications in patients who were maintained on their anticoagulant or antiplatelet medications prior to cataract surgery.622-630However, alternatives to retrobulbar injections should be considered for these patients.619
There are no recommendations from either the American Heart Association631,632 or the American Academy of Orthopaedic Surgeons to prescribe systemic antibiotic prophylaxis for patients with artificial heart valves or joint prostheses who are undergoing cataract surgery.633
Combined Surgery and Special Circumstances
Cataract Surgery and Glaucoma
When a candidate for cataract surgery also has glaucoma, surgical treatment options include cataract and IOL surgery alone, combined cataract and glaucoma surgery, glaucoma surgery after cataract surgery, or cataract surgery after glaucoma surgery. Glaucoma surgical options include traditional procedures such as trabeculectomy and other filtration procedures, drainage devices, and endocyclophotocoagulation.
Cataract surgery with IOL implantation alone results in a modest reduction of IOP, which may be particularly advantageous for patients with suspected or confirmed primary angle closure or for mild to moderately severe open-angle glaucoma controlled on medication.48 Studies have found that the degree of IOP reduction is greater with higher preoperative IOP levels and that the benefit may last for several years.41-44,47
Generally, a combined phacotrabeculectomy is not as effective as glaucoma surgery alone in lowering IOP.48,675 Both one-site and two-site combined procedures appear to provide similar IOP reduction.676 Phacoemulsification combined with trabeculectomy provides good IOP control as well as improved BCVA compared with preoperative vision.677-679 A variety of new glaucoma technologies may be combined with cataract surgery. These include canaloplasty,680 ab interno trabeculotomy,681682 and ab interno trabecular bypass microstents683 implantedat the time of cataract surgery. Compared with traditional filtering surgery with antimetabolite usage, these adjunctive technologies may reduce the risk of hypotony and bleb complications, but they may not lower the IOP as much.45,684
Potential benefits of a combined procedure (cataract extraction with IOL implantation and trabeculectomy) are protection against a potential postoperative IOP spike and long-term IOP control with a single operation.48
Although potentially indicated in eyes with active uveitis, neovascularization, or multiple anterior segment problems, there are disadvantages to performing filtration surgery as a separate procedure prior to cataract surgery. These include increased perioperative and anesthetic risks and the possibility of inducing filtration failure as a result of subsequent cataract surgery.
The benefit of the adjunctive use of antifibrotic agents (mitomycin-C and 5-fluorouracil) to reduce the potential for bleb failure in combined phacotrabeculectomy remains controversial. While it appears that mitomycin-C may be effective in producing lower long-term IOPs when used with combined procedures, 5-fluorouracil is not.48,675,685 Potential vision-threatening complications, such as bleb-related endophthalmitis,686-688 hypotony maculopathy,689,690 and late-onset bleb leaks691 should be considered in the decision to use antifibrotic agents.
The decision about the various surgical treatment options will be based on a number of factors, including the patient's response to medical or laser surgical treatment of the glaucoma, the degree of optic nerve damage, changes in the visual field, severity of the cataract, and the surgeon's experience.
Cataract Surgery and Keratoplasty
The presence of endothelial dystrophy presents a challenge to the cataract surgeon in predicting how well the compromised cornea will function following cataract surgery. Evaluation of the corneal endothelium is helpful in assessing the cataract patient preoperatively. A slit-lamp biomicroscopic examination that demonstrates microcystic edema or stromal thickening, and/or central corneal pachymetry greater than 640 microns,578 and/or low central endothelial cell counts by specular microscopy indicate an increased likelihood of corneal failure following cataract surgery. A history of prolonged "foggy vision" upon awakening in the morning often indicates significant endothelial pump impairment. If the lack of evaporation while asleep leads to symptomatic corneal edema, then the likelihood of decompensation after cataract surgery is high. Under these circumstances, a combined procedure of cataract extraction, IOL implantation, and corneal transplantation may be considered. With borderline endothelial reserve, a more peripheral incision, either temporal clear cornea or corneoscleral, and repeated instillation of OVD may preserve more endothelial cells.692
There are several reasons to consider combining cataract extraction with corneal transplantation, even in the presence of a mild cataract. These benefits include the following:
- Cataracts may progress more rapidly after corneal transplantation
- The use of topical corticosteroids following surgery may hasten PSC cataract development
- Cataract surgery subsequent to corneal transplantation may damage the corneal graft
- Surgery is limited to a single procedure
- Visual rehabilitation is more rapid
The use of capsule staining dyes may improve the likelihood of achieving an intact capsulorrhexis when performing a combined corneal transplant and cataract extraction.693
Because the postpenetrating keratoplasty corneal curvature is not known at the time of a combined procedure, IOL calculations are less accurate.694 Therefore, some surgeons prefer to perform penetrating keratoplasty first, followed by cataract removal later after the corneal graft has stabilized. If the cataract is removed following suture removal and stabilization of corneal graft keratometry, a more predictable IOL power and, hence, refractive result may be possible.695-697In some cases, this approach has the advantage of reducing the amount of time the eye is open during the penetrating keratoplasty surgery. These considerations apply to deep anterior lamellar keratoplasty as well.
An alternative to penetrating keratoplasty for the treatment of endothelial decompensation is transplantation of the endothelium and posterior stroma or replacement of the endothelial layer with Descemet's membrane alone.698,699These procedures can be combined with phacoemulsification and foldable IOL implantation. Among other potential advantages, this approach preserves the anterior corneal curvature and, therefore, should improve IOL power predictability compared with combined penetrating keratoplasty and cataract surgery. Descemet's stripping endothelial keratoplasty has been shown with both OCT and Scheimpflug imaging to induce a hyperopic refractive shift due to the change in the posterior corneal contour. Although it decreases over time, the hyperopic shift (approximately +0.6 D after 12 months in one study700 and +1.47 D from the expected biometry result in a second study701) should be considered if there is significant risk of corneal decompensation following cataract surgery.700,701
Unfortunately, studies to date have shown great variability in this hyperopic shift. One showed a mean decreased corneal power of 1.94 D in comparison to controls,702 while another reported a mean outcome of +1.63 D from the expected result looking at combined corneal and cataract surgery (range of 0 to 4.0 D).703 A third showed only a 0.15 D hyperopic shift that was not statistically different from the preoperative refraction.704 This great variability depends on how the posterior corneal transplant is fashioned, so it is best to check with the corneal surgeon to determine the expected result and adjust the final IOL power accordingly. This will be less of a problem with Descemets' membrane endothelial keratoplasty (DMEK), where the reported hyperopic shift was 0.49 D (range from -1.00 to +1.50).705
If the indication for considering corneal transplantation is the presence of a central opacity rather than endothelial dysfunction and adequate clear cornea is present in the midperiphery, the surgeon has the option of performing cataract surgery followed by a sphincterotomy, establishing a clear entrance pupil.706 The use of a capsule-staining dye can facilitate the ability to perform cataract surgery safely in the presence of a mild corneal opacity, possibly avoiding the need for corneal transplantation when the principal indication for a corneal transplant is to improve surgical visualization.707
Cataract Surgery and Uveitis
There are special issues to consider when patients with uveitis undergo cataract surgery.708,709 Patients with active anterior segment inflammation are at substantial risk for postoperative problems. Patients with anterior or intermediate uveitis are at particular risk of postoperative complications. A major potential problem, especially among patients with pre-existing iris damage or extensive posterior synechiae, is the development of adhesions between the iris and lens capsule postoperatively. Other potential problems include membrane formation, IOL deposits, zonular problems, and CME.
The optimal timing of cataract surgery in the presence of uveitis is a function of many factors. Inflammation should be inactive or at its best level of control prior to elective surgery.605 Even if the patient is on chronic anti-inflammatory therapy, additional topical or oral corticosteroids are often prescribed prior to surgery. In one study, pre-operative treatment with oral corticosteroids seemed to decrease the risk of postoperative CME.710 The medical regimen should be individualized based on the severity and sequelae of past episodes of uveitis and the ease with which inflammation has been previously controlled. Surgical planning should take into account the possible need for other procedures, which are often required because of associated uveitic complications such as secondary glaucoma. Surgical procedures may need to be modified to manage pre-existing posterior synechiae, pupillary membranes, and fibrotic scarring of the pupillary margin.
The safety of IOLs in most eyes with uveitis is now generally accepted. Intraocular lens material does not seem to be a major influence on the course of postoperative inflammation. Intraocular lens-related complications may include inflammatory deposits, surface membrane formation, and inflammatory capsular complications capable of causing IOL subluxation. Leaving the eye aphakic may be considered in severely damaged uveitic eyes with extensive pupillary or ciliary membrane formation or signs of intractable inflammation such as hypotony and severe flare. In most cases, standard placement of the IOL haptics into the capsular bag is preferred; however, sulcus fixation of the haptics may allow the IOL to block the formation of iridocapsular adhesions in high-risk eyes (e.g., extensive iris damage or pre-operative posterior synechiae). This technique does not seem to increase postoperative inflammation.601 With capsular bag placement, a large diameter capsulorhexis may also decrease the risk of postoperative synechiae to the anterior capsule. Anterior chamber IOLs may stimulate more inflammation and may be problematic if the angle anatomy is compromised.
Although the pupil may dilate poorly in eyes with uveitis, excessive iris manipulation should be avoided so as not to exacerbate inflammation and stimulate new posterior synechiae formation. Postoperative use of short-acting topical mydriatic agents may help to prevent postoperative synechiae formation; however, fixed dilation with long-acting cycloplegic agents such as atropine may lead to formation of posterior synechiae in the dilated state. Adjunctive corticosteroids at the time of surgery (intravenous, periocular, or intraocular) may be considered. Postoperatively, eyes with uveitis generally require greater frequency and duration of topical corticosteroid treatment and should be monitored closely for complications such as severe iridocyclitis, secondary glaucoma, posterior synechiae, secondary membranes, and CME.711
Cataract Surgery and Vitreoretinal Surgery
Cataract surgery is often necessary prior to, during, or following vitreoretinal surgery. Vitreoretinal procedures, including intravitreal injections, may cause pre-existing cataracts to progress, typically manifesting as increased nuclear sclerosis.712-717 Management of such cataracts may be more complex, because capsular defects or weakened zonules may be present.
Combined vitreoretinal and cataract surgery offers the advantage of a single operative procedure and anesthesia, potentially faster recovery, and cost-effectiveness.718 A wide range of vitreoretinal disorders may be dealt with concomitantly including vitreous hemorrhage, diabetic retinopathy, epiretinal membrane, macular hole, and retinal detachment.719-721 Phacoemulsification with in-the-bag placement of a foldable IOL is a good option when combined with many vitreoretinal procedures. However, pars plana lens fragmentation with simultaneous or later sulcus placement of a posterior chamber IOL is still often employed for more complex cases.722 Secure wound closure is important to permit safe vitreoretinal maneuvers.723-725 Surgeons should consider the nature of the posterior segment pathology and need for visualization when selecting the IOL style, biomaterial, and optic size.71,726,727 Specifically, intraoperative visualization of the posterior segment may become impaired when a silicone optic comes into contact with silicone oil or a gas bubble. A mild myopic shift has been recognized in some cases of combined surgery.728,729
Possible disadvantages of simultaneous cataract and vitreoretinal surgery include prolonged surgical time, cataract-wound dehiscence caused by globe manipulation during subsequent vitreoretinal surgery, intraoperative miosis after cataract extraction, IOL decentration or optic capture, and undesirable optical effects during vitreoretinal surgery if the IOL is implanted before the posterior segment procedure.
Cataract Surgery Following Refractive Surgery
Patients who have had prior corneal refractive surgery present a number of challenges for IOL power calculation. In addition to an inability to measure the central corneal power accurately, many IOL formulas predict the effective lens position based on the corneal steepness. Keratorefractive steepening or flattening of the cornea therefore introduces a formula artifact. Surgical strategies vary with the nature of the prior refractive surgery.
Following radial keratotomy, it is best to avoid having the new cataract-surgery incision cross or intersect pre-existing incisions, as this could lead to incision dehiscence, wound leak, delayed healing, and irregular astigmatism.730-733 Microincision methods may be helpful in this situation, and when many incisions are present, a scleral incision may lessen the chance of involving the original incisions.
In general, prior laser refractive surgery does not cause anatomic challenges during cataract surgery. On the other hand, in cases with previously implanted phakic refractive IOLs, the refractive IOL must be removed prior to or concomitant with cataract surgery.
Each type of refractive surgery presents a unique problem for determining the correct IOL power.
In the case of radial keratotomy, the induced central corneal flattening renders traditional keratometric readings inaccurate. This is because keratometers estimate the central corneal curvature based on paracentral measurements, and they will therefore fail to detect the full degree of central flattening.734,735 The clinical history method (which requires knowledge of presurgical keratometry and refraction) is generally not helpful following radial keratotomy due to the common occurrence of progressive central corneal flattening (hyperopic drift) that may continue for years to decades. Certain specific forms of automated computerized videokeratography (topography or tomography) can help in determining true central corneal power.736,737
After excimer laser refractive surgery (by either surface or intrastromal photoablation), corneal power readings with traditional keratometers, automated refractors, and topographers are often incorrect as result of the surgical alteration of the anterior corneal curvature and the changed relationship between anterior and posterior corneal powers. As a result, there is a tendency for hyperopic refractive errors after cataract surgery in eyes with prior myopic photoablation.653,738-741 Similarly, eyes that have had prior hyperopic photoablation are prone to myopic optical errors after cataract surgery.
A number of calculation methods and correction algorithms, some of which require knowledge of prior corneal power, refraction, and the change in manifest refraction, have been developed to help determine IOL power following refractive surgery, but there is presently no consensus about a best method.742-747 It may be beneficial to utilize the Aramberri Double-K method to refine IOL power determination, because the surgically altered corneal curvature may render some calculation formulas less accurate.748 Patients should be informed of the potential inaccuracies of IOL power calculation and that further surgery may be necessary to achieve the desired target refraction.
In order to bring together the most accurate IOL power calculation methodologies for patients who have previously undergone radial keratotomy, myopic or hyperopic photoablation, ASCRS has developed a regularly updated online IOL power calculator available at http://iol.ascrs.org or http://one.aao.org/ce/iol.html.244,749
Postoperative corneal hydration or edema and elevated IOP may amplify the effect of radial keratotomy incisions, causing transient hyperopia and changes in astigmatism. The timing of any further refractive surgical intervention should be delayed until the refraction is stable.730
Cataract in the Functionally Monocular Patient
A functionally monocular patient is one who is primarily dependent on the eye being considered for cataract surgery. There may be significant ocular comorbidity or other high-risk characteristics in such eyes.750,751 The indications for surgery in the functionally monocular patient are the same as for other patients; that is, when the cataract-impaired vision no longer meets the patient's needs and the anticipated benefits of surgery exceed the risks. Cataract surgery for these patients results in a greater improvement in functional vision than surgery in binocularly sighted patients.752 When cataract surgery is contemplated in a functionally monocular patient, the ophthalmologist has an obligation to inform the patient that blindness is one of the risks of cataract surgery and that it can also result from worsening ocular comorbidity following surgery.753
The ophthalmologist and patient should consider that delaying surgery until the cataract is very advanced may increase surgical risk and slow visual recovery.
Clinical studies have providedconvincing evidence that binocular summation occurs in individualswho have similar visual acuities in the two eyes and at low illuminance levels.754-759 In addition, these studies have demonstratedthat binocular gain or summation is less likely when the visualacuities in the two eyes are dissimilar or when the individualis older. Indeed, these individuals with dissimilar acuitiesin the two eyes may exhibit binocular inhibition. Patients with a cataract and dissimilar visionin the two eyes (or one eye with cataract extraction and the second eye with a cataract) have demonstrated binocular inhibition.759 A large epidemiological study demonstrated that persons who exhibited binocular inhibition were more likely to have driving difficulties compared with those who did not have binocular inhibition.754 These data taken together suggest an improvement in binocular visual function and quality of life if cataract surgery in the second eye provides similar visual acuities in the two eyes.
Studies comparing the outcomes of first- and second-eye cataract surgeries concluded that patients who had surgery in both eyes had greater improvement in functional status than those who underwent surgery in only one eye.173,760-765 Patients who had surgery in both eyes were significantly more satisfied with their visual function than patients who had surgery in only one eye.760,766 Another study demonstrated that the cataractous eye interfered with the visual function of the pseudophakic eye and that complaints of visual disability were eliminated after second-eye surgery.767 One study found that stereoacuity increased from 32% of patients after first-eye surgery to 90% after second-eye surgery. Also, binocular horizontal field of vision improved in 36% of patients. The number of patients able to meet the driving standard increased from 52% after first-eye surgery to 86% after second-eye surgery.768 Cataract surgery for both eyes is an appropriate treatment for patients with bilateral cataract-induced visual impairment.760,762,763,769
The indications for second-eye surgery are the same as for the first eye. The outcome of surgery on the first eye may affect the timing of second eye surgery. In some patients, a byproduct of reducing ametropia in the first operated eye may be anisometropia. This may result in impaired stereoacuity and a reduction in a patient's ability to perform daily activities. In patients whose anisometropia interferes with visual function, second-eye surgery may be appropriate at an earlier stage of cataract development.762,770
Determining the appropriate interval between the first-eye surgery and the second-eye surgery is influenced by several factors: the patient's visual needs and preferences, visual acuity and function of the second eye, the medical and refractive stability of the first eye, and the degree of anisometropia. Prior to performing second-eye surgery, the refractive error of the first eye should be determined in order to select the appropriate IOL power for the second eye.771,772
One study has suggested that a change in refraction from 1 week to 1 month postoperatively of 0.5 D or more occurs in only 1.2% of patients.771
Sufficient time should elapse to diagnose and treat any early postoperative complication such as endophthalmitis, and for the patient and the ophthalmologist to be satisfied with the recovery and outcome of the first-eye surgery.
Immediate Sequential (Same Day) Bilateral Cataract Surgery
Most ophthalmologists do not perform immediate sequential bilateral cataract surgery on the same day. The rapid visual recovery and low complication rates associated with small-incision cataract surgery under topical anesthesia has led to increased interest in this approach in some international centers,773-786particularly in health care delivery systems with long waiting times for cataract surgery in the second eye.773,783-785Prospective comparative trials of immediate sequential (same day) versus delayed sequential (different day) cataract extraction document some cost reduction with same-day bilateral surgery and a short-term functional advantage until the second surgery is performed.780-785 Assuming that it is the preference of a patient anticipating cataract surgery in both eyes, immediate sequential bilateral surgery has advantages and disadvantages that must be carefully weighed and discussed by the surgeon and patient. Foremost is the risk of potentially blinding complications in both eyes. For this reason the second eye should be treated like the eye of a different patient using separate povidone iodine prepping, draping, instrumentation, and supplies such as irrigating solutions, OVD, and medications. In published reviews, bilateral complications are rare,773-779but there have been case reports of bilateral endophthalmitisoccurring with simultaneous surgery when these guidelines for strict separation of the two surgical setups were not followed.781782,787,788
Another potential disadvantage of this approach is the inability to adjust surgical plans for the second eye on the basis of results from the first eye surgery.772 In addition to an unanticipated refractive outcome in the first eye, IOL selection for the second eye may also be altered because the patient decides on a different refractive target or type of IOL based on his or her experience with the first eye.772
Indications that have been reported for immediate sequential bilateral cataract surgery include the need for general anesthesia in the presence of bilateral visually significant cataracts, rare occasions where travel for surgery and follow-up care is a significant hardship for the patient, and when the health of the patient may limit surgery to one surgical encounter.774,777,786
Discharge from Surgical Facility
Typical criteria for discharge after ambulatory surgery are as follows:
- Vital signs are stable
- Preoperative mental state is restored
- Nausea and vomiting are controlled
- Pain is absent or minimal
- An escort is available if necessary
- Postsurgical care has been reviewed with the patient and/or escort and written postoperative instructions have been provided
- A follow-up appointment has been scheduled
Operative complications of an ocular or medical nature are possible indications for transfer and postoperative hospitalization. In the Study of Medical Testing for Cataract Surgery (n=19,250 surgeries), there were 61 (0.3%) hospitalizations on the day of cataract surgery.231 Ocular complications that may require hospitalization include hyphema, uncontrolled elevated IOP, threatened or actual expulsive suprachoroidal hemorrhage, retrobulbar hemorrhage, severe pain, other ocular problems requiring acute management or careful observation. Medical complications can include cardiac or respiratory instability, a cerebrovascular episode, diabetes mellitus or hypertension requiring acute management, uncontrolled nausea or vomiting, acute urinary retention, acute psychiatric disorientation, or other medical conditions requiring management in an acute-care setting with careful monitoring.
Situations under which extended observation might be warranted include the following:
- Medical conditions are present that require prolonged postoperative observation by nurses or other skilled personnel
- Patient is mentally debilitated or diagnosed as mentally ill
- Patient cannot exercise self-care (or responsible care is unavailable) during the immediate postoperative period
- Patient is functionally monocular and has had cataract surgery in the eye on which he or she is dependent
The ophthalmologist who performs the cataract surgery has a unique perspective and thorough understanding of the patient's intraoperative course, postoperative condition, and response to surgery. The operating ophthalmologist is responsible for the care of the patient during the postoperative interval, the time in which most complications occur and within which stable visual function is achieved, as well as an ethical obligation to the patient that continues until postoperative rehabilitation is complete.
The operating ophthalmologist should also provide those aspects of postoperative eye care that are within the unique competence of the ophthalmologist. These do not necessarily include those aspects of postoperative care permitted by law to be performed by auxiliaries. If such follow-up care is not possible, the operating ophthalmologist must make arrangements before surgery to refer the patient to another ophthalmologist for postoperative care with the prior approval of the patient and the ophthalmologist.228,789,790 In rare special circumstances, such as emergencies or if no ophthalmologist is available, the operating ophthalmologist may make different arrangements for the provision of those aspects of postoperative eye care within the unique competence of the ophthalmologist, as long as the patient's rights and welfare are the primary considerations.
The ophthalmologist who performs surgery has an obligation to inform patients about appropriate signs and symptoms of possible complications, eye protection, activities, medications, required visits, and details for access to emergency care. The ophthalmologist should also inform patients of their responsibility to follow advice and instructions provided during the postoperative phase and to notify the ophthalmologist promptly if problems occur. Patients should always have access to an ophthalmologist for appropriate care if serious problems arise.
Most ophthalmologists provide all postoperative care in their offices. Other members of a team of eye care professionals may also participate in the comanagement of postoperative care. The operating ophthalmologist is responsible to the patient for those aspects of postoperative care delegated to other eye care professionals.228
Postoperative regimens of topically applied antibiotics, corticosteroids, and NSAIDs vary among practitioners. There are no controlled investigations that establish optimal regimens for the use of topical agents; therefore, it is the decision of the operating surgeon to use any or all of these products singly or in combination. Complications of postoperative medications include elevated IOP with corticosteroids and allergic reactions to antibiotics. Significant corneal reactions, including epithelial defects and stromal ulceration and melting, have rarely been reported with topical ocular NSAIDs.791-793
The frequency of postoperative examinations is based on the goal of optimizing the outcome of surgery and swiftly recognizing and managing complications. This requires prompt and accurate diagnosis and treatment of complications of surgery, providing satisfactory optical correction, educating and supporting the patient, and reviewing postoperative instructions. Table 5 provides guidelines for follow-up based on consensus in the absence of evidence for optimal follow-up schedules. Prospective studies from the United Kingdom have reported that omitting an examination on the day after uncomplicated cataract surgery for the routine patient was associated with a low frequency of serious ocular complications.794-797
TABLE 5. Postoperative Follow-up Schedule (PDF 71k)
Patients should be instructed to contact the ophthalmologist promptly if they experience symptoms such as a significant reduction in vision, increasing pain, progressive redness, or periocular swelling, because these symptoms may indicate the onset of endophthalmitis.
In the absence of complications, the frequency and timing of subsequent postoperative visits depend largely on the size or configuration of the incision; the need to cut or remove sutures; and when refraction, visual function, and the medical condition of the eye are stabilized. More frequent postoperative visits are generally indicated if unusual findings, symptoms, or complications occur, and the patient should have ready access to the ophthalmologist's office to ask questions or seek care.
Components of each postoperative examination should include the following:
- Interval history, including use of postoperative medications, new symptoms, and self-assessment of vision
- Measurement of visual function (e.g., visual acuity, including pinhole testing or refraction when appropriate)
- Measurement of IOP
- Slit-lamp biomicroscopy
- Counseling/education for the patient or patient's caretaker
- Management plan
A dilated fundus examination is indicated if there is a reasonable suspicion or higher risk of posterior segment problems. In the absence of symptoms or surgical complications, no study has demonstrated that a dilated fundus examination results in earlier detection of retinal detachment.
When postoperative visual improvement is less than anticipated, the ophthalmologist may perform additional diagnostic testing to evaluate the cause. For example, if maculopathy is suspected, OCT or fluorescein angiography would be appropriate to diagnose cystoid or diffuse macular edema, epiretinal membranes, or AMD. Likewise, corneal topography could diagnose irregular corneal astigmatism. Automated visual fields may diagnose a neuro-ophthalmic abnormality. Other testing may be conducted if appropriate.
A final refractive visit should be made to provide an accurate prescription for eyeglasses to allow for the patient's optimal visual function. The timing and frequency of refraction will depend on patient needs and the stability of the measurement. Sutures, if used, may be cut or removed by the ophthalmologist to reduce astigmatism. Optical correction can usually be prescribed between 1 and 4 weeks after small-incision cataract surgery798 and between 6 and 12 weeks after sutured large-incision cataract extraction surgery.
Posterior Capsular Opacification
Posterior capsular opacification often occurs following ECCE by any method and can cause a gradual decrease in visual function. In a comparative study, the incidence of PCO was significantly higher at 1 year in the manual ECCE group than in the phacoemulsification group.385 Analysis of 23 randomized controlled trials found that sharp-edged hydrophobic acrylic IOLs and silicone IOLs were more effective in preventing PCO and Nd:YAG laser capsulotomy than PMMA IOLs and hydrophilic acrylic (hydrogel) IOLs. A Cochrane systematic review found no significant differences in PCO development between different IOL materials (PMMA, hydrogel, hydrophobic acrylic, and silicone). However, the hydrogel IOLs tended to have higher PCO scores and the silicone IOLs had lower PCO scores than the other IOL materials. This analysis did find that there was a significantly lower PCO score and Nd:YAG laser capsulotomy rate with sharp-edged versus round-edged IOLs.806
Substantial evidence supports a lower PCO rate when the anterior capsulorrhexis completely overlaps the entire optic.807,808 However, this may be a less important factor with single-piece foldable acrylic IOLs.809
Polishing of the anterior capsule has a variable effect on reducing PCO rates.810,811 However, anterior capsule fibrosis and contracture is more frequent with silicone than acrylic optic materials, and anterior capsule polishing may reduce this postoperative phenomenon.810-812 No difference in PCO rates has been found with more prolonged administration of topical corticosteroids or topical NSAIDs.655-657
Nd:YAG laser capsulotomy is an effective surgical procedure to clear the visual pathway and restore visual function, and to improve contrast sensitivity.813The indication for performing Nd:YAG laser capsulotomy is PCO consistent with an impairment of vision to a level that does not meet the patient's functional needs or that critically interferes with visualization of the fundus. The decision to perform capsulotomy should take into account the benefits and risks of the laser surgery. Posterior capsulotomy may be indicated earlier in patients with multifocal IOLs because of a greater functional impact of early PCO in low-contrast and glare conditions. These lenses reduce contrast sensitivity, which is further impaired by early PCO. Nd:YAG laser capsulotomy should not be performed prophylactically (i.e., when the capsule remains clear). Same-day bilateral Nd:YAG laser posterior capsulotomy may be appropriate when indicated.
Complications of Nd:YAG laser capsulotomy include increased IOP,814 retinal detachment, damage to the IOL, and dislocation of the IOL.815 Axial myopia increases the risk of retinal detachment after Nd:YAG laser capsulotomy,816 as does pre-existing vitreoretinal disease, male gender, young age, vitreous prolapse into the anterior chamber, and spontaneous extension of the capsulotomy.817 Two case series reported a 0% to 0.4% incidence of retinal detachment 1 to 8 years following uncomplicated phacoemulsification and capsular fixation of the IOL.499,818 In one of these series, there were no retinal detachments in eyes with an axial length less than 24.0 mm.499A case-control study found that, in the absence of a posterior capsule tear at the time of cataract surgery, subsequent Nd:YAG capsulotomy did not increase the risk of retinal detachment.819
In the absence of risk factors for IOP elevation, routine prophylaxis with ocular hypotensive agents at the time of capsulotomy is not consistently supported by the literature.820,821 In the presence of risk factors, such as pre-existing glaucoma or inflammation, a variety of agents to lower IOP have demonstrated efficacy at blunting IOP elevation.822-827 Therefore, in high-risk patients, the surgeon should monitor the IOP in the early postoperative period.
Because retinal breaks or detachments are acute events that can occur weeks to years after laser capsulotomy, a routine dilated fundus examination is unlikely to detect retinal pathology that requires treatment in the absence of symptoms. Educating high-risk patients about the symptoms of retinal tears or detachment may facilitate early diagnosis.828
PROVIDER AND SETTING
It is the unique role of the ophthalmologist who performs cataract surgery to confirm the presence of the cataract, determine the need for surgery, and formulate and carry out a treatment plan, including postoperative care.227,228Diagnosis and management require medical expertise, surgical skills, and specialized diagnostic and surgical equipment. The ophthalmologist's training, clinical experience, and judgment are necessary to evaluate the medical, ocular, and psychosocial factors used to determine the appropriateness and timing of surgery. Cataract surgery, including use of the femtosecond laser, should be performed only by an appropriately trained ophthalmologist.829
While the performance of certain diagnostic procedures (e.g., measurement of IOP, refraction, biometry) may be delegated to appropriately trained personnel supervised by the ophthalmologist, interpretation of these procedures requires the clinical judgment of the ophthalmologist.
Nearly all cataract surgery is performed in an outpatient setting, which may be in a hospital-based outpatient department (HOPD) or freestanding ambulatory surgery center (ASC). The surgical facility should comply with local, state, and federal regulations and standards governing the particular setting of care. Inpatient surgery may be necessary if there is a need for complex anesthetic or surgical care, multiple procedures, or postoperative care requiring an acute-care setting.
COUNSELING AND REFERRAL
Patients with functionally limiting postoperative visual impairment should be referred for vision rehabilitation and social services.830 More information on vision rehabilitation, including materials for patients, is available at www.aao.org/smartsight.
Utilization of Cataract Surgery in the United States
In 2010, a total of 1.82 million cataract procedures were performed on Medicare beneficiaries who were not enrolled in health maintenance organizations. A longitudinal study of Americans 62 or older (n=8670 in 1998) estimated that the annual rate of cataract surgery was 5.3% for the period January 1, 1995 to December 31, 2002.831 The study also found that the prevalence of unilateral pseudophakia increased from 7.6% in 1998 (n=8670) to 9.8% in 2002 (n=6199) and that the prevalence of bilateral pseudophakia increased from 10.5% in 1998 to 22.3% in 2002.
When assessed across populations residing in different states or metropolitan areas, there is some variation in the rate of cataract surgery, but these differences are relatively low compared with geographic variations observed with other surgical procedures. In one study, factors associated with a higher rate of cataract surgery were female gender, living in a more southerly latitude, a higher concentration of optometrists in a specific geographic area, and a higher allowed charge for cataract surgery.832 A higher concentration of ophthalmologists was not associated with a higher rate of cataract surgery. A decreased likelihood of undergoing cataract surgery was reported among African American Medicare beneficiaries when compared with Caucasian Americans.832The rate of cataract surgery in the Veterans Health Administration (VHA) ranged between 104.8 to 133.6 per 10,000 VHA beneficiaries in 2007. These figures include surgery performed in VHA hospitals and surgical centers and those performed outside the VHA system but paid for by the VHA.833
The utilization of cataract surgery in the United States has been found to be appropriate for the majority of cases studied. A study at 10 academic medical centers found that 2% of cataract surgeries performed were classified as inappropriate based on available records.34 An inappropriate rating meant that the risks of surgery were deemed to exceed the potential benefits as rated by a physician review panel. The percentage deemed inappropriate in this study correlates to earlier estimates of 2.5% by the 1993 U.S. General Accounting Office and a rate of 1.7% by the U.S. Inspector General.34 Cataract appropriateness ratings are comparable to the rate found for coronary artery bypass graft surgery (2.4% inappropriate) and lower than the rate for carotid endarterectomies (10.6% inappropriate).834,835 The criteria for appropriateness of cataract surgery were based on indicators of visual acuity and functional impairment, such as difficulty driving, reading, and other activities of daily living. The study did note that the information that was recorded varied, particularly on functional impairment, and increased attention to documenting specific functional impairments is appropriate. A study of Medicare beneficiaries in 13 large areas in the United States found that cataract surgery ranked among procedures with the least variation in use.836 Also, second-opinion programs implemented for cataract surgery have not lowered surgical rates, because the initial recommendations for surgery were found to be appropriate. The validity of the appropriateness methodology used to evaluate the utilization of cataract surgery was supported by a study of the association between the appropriateness rating and postoperative visual acuity.837 More recent studies have added a self-reported visual function questionnaire.838 For a sample of 768 patients, 89% of those who had surgeries rated as appropriate were found to have a visual acuity improvement of at least 2 lines postoperatively. For the group that had surgeries rated as inappropriate, 36% had a visual acuity improvement of at least 2 lines postoperatively. This finding suggests that the functional benefit of cataract surgery can be unpredictable in some individuals and cannot always be accurately predicted preoperatively.
Cost of Cataract Surgery in the United States
Since the first freestanding ASCs were started in the early 1970s, there has been a significant movement of eye surgery from HOPDs to ASCs. According to the Medicare Payment Advisory Commission, ASCs may offer more convenient locations, shorter waiting times, and easier scheduling for patients compared with HOPDs.839 In 2009, 69% of cataract surgery with IOL insertion was performed in ASCs.840 Medicare payments to ASCs for all types of surgery totaled $3.2 billion or $102 per Medicare beneficiary in 2009.841 Cataract surgery with IOL implantation was the most frequently performed surgical service in ASCs in 2009, accounting for 18% of the volume.842 Eye procedures accounted for 46% of total Medicare ASC payments. In 2010, the Medicare facility payment to an ASC for cataract surgery was $961.34 and $1637.15 for an HOPD. Patients' coinsurance payments are lower in an ASC facility at $192 compared with $327 in HOPDs. Cataract surgery with IOL implantation accounted for 40% of Medicare eye-procedure payments.
The 2006 National Survey of Ambulatory Surgery by the Centers for Disease Control and Prevention's National Center for Health Statistics found that the total operating room times (including surgery and turnover) were over 50% longer in HOPDs.843
In 2010, the national average surgeon reimbursement for cataract surgery/IOL implantation was $713.86. Since the institution of the Resource-Based Relative Value Scale in 1992, there has been a 40% decrease in this fee, not adjusted for inflation. The total cost for cataract surgery/IOL implantation for a Medicare beneficiary in the ASC setting is about $2335 for 2010. This includes the initial office evaluation as well as refraction, biometry, surgical facility fee, surgeon and anesthesia professional fees, medications, and new postoperative eyeglasses. The Medicare patient's copayment is approximately $450. Typically, the facility fee for cataract surgery/IOL implantation will be approximately 50% higher in the HOPD setting.
Cataract surgery with IOL implantation was the most frequently performed operation and the single largest expenditure for any Part B procedure in the Medicare program, calculated by Part B procedure codes based on allowed charges. In 2009 (latest year available), payment for cataract was $2.1 billion, which is 1.8% of total allowed charges.844
Cost-effectiveness of Cataract Surgery
Methods to evaluate whether the cost of a medical intervention is a good use of available resources include cost-effectiveness or cost-utility calculations. The quality-adjusted life year (QALY) is a measure of a disease burden, including both the quality and the quantity of life lived. It is used in assessing the monetary value of a medical intervention. The QALY is based on the number of years of life that would be added by the intervention. Each year in perfect health is assigned the value of 1.0 down to a value of 0.0 for death. If the extra years would not be lived in full health, for example, if the patient would be blind, lose a limb, or have to use a wheelchair, then the extra life-years are given a value between 0 and 1 to account for this. The QALY is used in cost-utility analysis to calculate the ratio of cost to QALY improvement and compare the value of interventions of different health conditions. Lower cost per QALY represents a more cost-effective medical intervention.
Estimates of the hypothetical cost per QALY gained for cataract surgery in one eye was estimated at US$4500 in Sweden845 and US$2023 in the United States.846 In a U.S. study done in 2003, the estimated cost per QALY gained for cataract surgery in the second eye was US$2727.847 These calculations compare favorably with other medical treatments. Single-vessel coronary artery bypass surgery for disease of the left anterior descending artery costs $7000/QALY, treatment of arterial hypertension costs $58,000/QALY, and ambulatory peritoneal dialysis costs $90,000/QALY.
Medical technology is valuable if the benefits of medical advances exceed the costs. Cutler and McClellum analyzed technological advances in treatment of five conditions, including cataracts.27 In four of the conditions-heart attacks, low-birthweight infants, depression, and cataracts-the estimated benefit of technological changes is much greater than the cost. The medical advances in cataract surgery from the late 1960s to present have resulted in increased safety and improved outcomes. One estimate of the present benefit value of cataract surgery is $95,000, which is far greater than the cost of treatment at $2300 to $3000. This value compares favorably with the estimated present values for other treatments: $20,000 for breast cancer, $6000 for depression, $240,000 for a low birthweight infant, and $70,000 for a heart attack. These various analyses suggest that on a relative basis, cataract surgery is very cost-effective and beneficial for the patient and society.
With large projected increases in the elderly population worldwide, the significant cost burden of cataract surgery will continue to increase for every global medical system. Because of the societal imperative that cataract surgery be both safe and cost-effective, it is important to evaluate unproven and potentially unnecessary practices based on carefully monitored studies of surgical outcomes. In many countries, sterilization and aseptic protocols for ophthalmic surgery have been arbitrarily defined by national regulatory agencies. Many of these measures originated from studies in nonophthalmic specialties and may not be specifically validated for ophthalmic surgery, where the source of most infections is the patient's own eyelid and external ocular flora. For example, using infection-control protocols based on continuous monitoring of outcomes data, one eye hospital in India reported an endophthalmitis rate of only 0.09% (0.02% of phacoemulsification cases) in more than 42,000 consecutive cataract surgeries using short-cycle steam sterilization and continuous reuse of gowns, gloves, surgical tubing, and irrigating solutions.298 Costlier new infection control measures for ophthalmic surgery should not be arbitrarily imposed by regulatory agencies without evidence-based support.
Physician Quality Reporting System
The Physician Quality Reporting System program, initially launched by the Centers for Medicare and Medicaid Services in July 2007, encourages quality improvement through the use of clinical performance measures on a variety of clinical conditions. There are two measures in the 2011 Physician Quality Reporting System program for cataract surgery. One measure is related to the visual outcome achieved and the other to major postoperative complications.848
APPENDIX 1. QUALITY OF OPHTHALMIC CARE CORE CRITERIA
Providing quality care
is the physician's foremost ethical obligation, and is
the basis of public trust in physicians.
AMA Board of Trustees, 1986
Quality ophthalmic care is provided in a manner and with the skill that is consistent with the best interests of the patient. The discussion that follows characterizes the core elements of such care.
The ophthalmologist is first and foremost a physician. As such, the ophthalmologist demonstrates compassion and concern for the individual, and utilizes the science and art of medicine to help alleviate patient fear and suffering. The ophthalmologist strives to develop and maintain clinical skills at the highest feasible level, consistent with the needs of patients, through training and continuing education. The ophthalmologist evaluates those skills and medical knowledge in relation to the needs of the patient and responds accordingly. The ophthalmologist also ensures that needy patients receive necessary care directly or through referral to appropriate persons and facilities that will provide such care, and he or she supports activities that promote health and prevent disease and disability.
The ophthalmologist recognizes that disease places patients in a disadvantaged, dependent state. The ophthalmologist respects the dignity and integrity of his or her patients, and does not exploit their vulnerability.
Quality ophthalmic care has the following optimal attributes, among others.
- The essence of quality care is a meaningful partnership relationship between patient and physician. The ophthalmologist strives to communicate effectively with his or her patients, listening carefully to their needs and concerns. In turn, the ophthalmologist educates his or her patients about the nature and prognosis of their condition and about proper and appropriate therapeutic modalities. This is to ensure their meaningful participation (appropriate to their unique physical, intellectual and emotional state) in decisions affecting their management and care, to improve their motivation and compliance with the agreed plan of treatment, and to help alleviate their fears and concerns.
- The ophthalmologist uses his or her best judgment in choosing and timing appropriate diagnostic and therapeutic modalities as well as the frequency of evaluation and follow-up, with due regard to the urgency and nature of the patient's condition and unique needs and desires.
- The ophthalmologist carries out only those procedures for which he or she is adequately trained, experienced and competent, or, when necessary, is assisted by someone who is, depending on the urgency of the problem and availability and accessibility of alternative providers.
- Patients are assured access to, and continuity of, needed and appropriate ophthalmic care, which can be described as follows.
- The ophthalmologist treats patients with due regard to timeliness, appropriateness, and his or her own ability to provide such care.
- The operating ophthalmologist makes adequate provision for appropriate pre- and postoperative patient care.
- When the ophthalmologist is unavailable for his or her patient, he or she provides appropriate alternate ophthalmic care, with adequate mechanisms for informing patients of the existence of such care and procedures for obtaining it.
- The ophthalmologist refers patients to other ophthalmologists and eye care providers based on the timeliness and appropriateness of such referral, the patient's needs, the competence and qualifications of the person to whom the referral is made, and access and availability.
- The ophthalmologist seeks appropriate consultation with due regard to the nature of the ocular or other medical or surgical problem. Consultants are suggested for their skill, competence, and accessibility. They receive as complete and accurate an accounting of the problem as necessary to provide efficient and effective advice or intervention, and in turn respond in an adequate and timely manner.
- The ophthalmologist maintains complete and accurate medical records.
- On appropriate request, the ophthalmologist provides a full and accurate rendering of the patient's records in his or her possession.
- The ophthalmologist reviews the results of consultations and laboratory tests in a timely and effective manner and takes appropriate actions.
- The ophthalmologist and those who assist in providing care identify themselves and their profession.
- For patients whose conditions fail to respond to treatment and for whom further treatment is unavailable, the ophthalmologist provides proper professional support, counseling, rehabilitative and social services, and referral as appropriate and accessible.
- Prior to therapeutic or invasive diagnostic procedures, the ophthalmologist becomes appropriately conversant with the patient's condition by collecting pertinent historical information and performing relevant preoperative examinations. Additionally, he or she enables the patient to reach a fully informed decision by providing an accurate and truthful explanation of the diagnosis; the nature, purpose, risks, benefits, and probability of success of the proposed treatment and of alternative treatment; and the risks and benefits of no treatment.
- The ophthalmologist adopts new technology (e.g., drugs, devices, surgical techniques) in judicious fashion, appropriate to the cost and potential benefit relative to existing alternatives and to its demonstrated safety and efficacy.
- The ophthalmologist enhances the quality of care he or she provides by periodically reviewing and assessing his or her personal performance in relation to established standards, and by revising or altering his or her practices and techniques appropriately.
- The ophthalmologist improves ophthalmic care by communicating to colleagues, through appropriate professional channels, knowledge gained through clinical research and practice. This includes alerting colleagues of instances of unusual or unexpected rates of complications and problems related to new drugs, devices or procedures.
- The ophthalmologist provides care in suitably staffed and equipped facilities adequate to deal with potential ocular and systemic complications requiring immediate attention.
- The ophthalmologist also provides ophthalmic care in a manner that is cost effective without unacceptably compromising accepted standards of quality.
Reviewed by: Council
Approved by: Board of Trustees
October 12, 1988
2nd Printing: January 1991
3rd Printing: August 2001
4th Printing: July 2005
APPENDIX 2. NUTRITION AND CATARACTS
Most randomized controlled studies of nutritional supplements have not demonstrated a beneficial effect on cataract development or progression (Table A2-1). Observational studies of nutrition and cataract with more than 10,000 participants (Table A2-2) have reported either no association849 or a reduced risk.850-855
TABLE A2-1. Summary of Randomized Controlled Trials of Nutritional Supplements and Cataracts (PDF 110k)
TABLE A2-2. Summary of Observational Studies of Nutrition and Cataracts (N >10,000) (PDF 106k)
APPENDIX 3. WRONG-SITE WRONG-IOL SURGERY CHECKLIST
Wrong-Site Wrong-IOL Surgery Checklist (PDF 177k)
This checklist may be downloaded from http://one.aao.org/CE/PracticeGuidelines/Patient.aspx. Choose the Recommendations of American Academy of Ophthalmology Wrong-Site Task Force Patient Safety Bulletin (November 2008) and click on Full Text.
LIST OF ABBREVIATIONS
ADVS: Activities of Daily Vision Scale
AMD: age-related macular degeneration
ASC: ambulatory surgery center
ASCRS: American Society of Cataract and Refractive Surgery
BCVA: best-corrected visual acuity
CME: cystoid macular edema
ECCE: extracapsular cataract extraction
ESCRS: European Society of Cataract and Refractive Surgeons
EVS: Endophthalmitis Vitrectomy Study
HEMA: hydroxy ethyl methacrylate
HOPD: hospital-based outpatient department
IFIS: intraoperative floppy iris syndrome
IOL: intraocular lens
IOP: intraocular pressure
Nd:YAG: neodymium: yttrium-aluminum-garnet laser
NEI-VFQ: National Eye Institute-Visual Function Questionnaire
NEON: National Eyecare Outcomes Network
NSAID: nonsteroidal anti-inflammatory drug
OVD: ophthalmic viscosurgical device
PCO: posterior capsular opacification
PMMA: polymethyl methacrylate
PORT: Patient Outcomes Research Team
PPP: Preferred Practice Pattern
PSC: posterior subcapsular
TASS: toxic anterior segment syndrome
QALY: quality-adjusted life year
VF-14: Visual Function Index
VHA: Veterans Health Administration
RELATED ACADEMY MATERIALS
Basic and Clinical Science Course
Lens and Cataract (Section 11, 2011-2012)
Expert Management DVDs
Challenging Cases in Cataract Surgery (2009)
Complications During Cataract Surgery: Anterior Capsule (2009)
Complications During Cataract Surgery: Posterior Capsule (2010)
Cataract Surgery in the Developing World (2011)
Patient Education Booklet
Cataract Surgery (2011)
Patient Education Brochures
Cataract (Spanish: Catarata) (2011)
Cataract Surgery (2011)
Eye Care Facts & Myths (2010)
Seeing Well as You Grow Older (2011)
Patient Education DVD
Understanding Cataract Surgery (2009) (includes English and Spanish)
Understanding IOL Options for Cataract Surgery (2009) (includes English and Spanish)
Patient Safety Bulletin
Recommendations of American Academy of Ophthalmology Wrong-Site Task Force (2008) - Available at: http://one.aao.org/CE/PracticeGuidelines/Patient.aspx
Performance Improvement CME
Wrong Site/Wrong IOL Performance Improvement CME - Available at: http://one.aao.org/ce/educationalcontent/performanceimprovementcme.aspx
Preferred Practice Pattern
Comprehensive Adult Medical Eye Evaluation (2010) - Available at: www.aao.org/ppp
To order any of these materials, please call the Academy's Customer Service number, 866.561.8558 (U.S. only) or 415.561.8540 or visit www.aao.org/store.
- Scottish Intercollegiate Guidelines Network. SIGN 50: a guideline developer's handbook. Available at: www.sign.ac.uk/methodology/index.html. Accessed May 4, 2011.
- Guyatt GH, Oxman AD, Vist GE, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336:924-6.
- GRADE Working Group. Organizations that have endorsed or that are using GRADE. Available at: www.gradeworkinggroup.org/society/index.htm. Accessed May 4, 2011.
- Schein OD, Steinberg EP, Javitt JC, et al. Variation in cataract surgery practice and clinical outcomes. Ophthalmology 1994;101:1142-52. [II+]
- Mangione CM, Phillips RS, Lawrence MG, et al. Improved visual function and attenuation of declines in health-related quality of life after cataract extraction. Arch Ophthalmol 1994;112:1419-25. [II+]
- Desai P, Minassian DC, Reidy A. National cataract surgery survey 1997-8: a report of the results of the clinical outcomes. Br J Ophthalmol 1999;83:1336-40. [II-]
- McGwin G Jr, Scilley K, Brown J, Owsley C. Impact of cataract surgery on self-reported visual difficulties: comparison with a no-surgery reference group. J Cataract Refract Surg 2003;29:941-8. [II-]
- Brenner MH, Curbow B, Javitt JC, et al. Vision change and quality of life in the elderly. Response to cataract surgery and treatment of other chronic ocular conditions. Arch Ophthalmol 1993;111:680-5. [II+]
- Ishii K, Kabata T, Oshika T. The impact of cataract surgery on cognitive impairment and depressive mental status in elderly patients. Am J Ophthalmol 2008;146:404-9. [III]
- Monestam E, Wachtmeister L. Impact of cataract surgery on visual acuity and subjective functional outcomes: a population-based study in Sweden. Eye 1999;13 (Pt 6):711-9. [II+]
- Steinberg EP, Tielsch JM, Schein OD, et al. National study of cataract surgery outcomes. Variation in 4-month postoperative outcomes as reflected in multiple outcome measures. Ophthalmology 1994;101:1131-40; discussion 1140-1. [II+]
- Harwood RH, Foss AJ, Osborn F, et al. Falls and health status in elderly women following first eye cataract surgery: a randomised controlled trial. Br J Ophthalmol 2005;89:53-9. [I+]
- Gray CS, Karimova G, Hildreth AJ, et al. Recovery of visual and functional disability following cataract surgery in older people: Sunderland Cataract Study. J Cataract Refract Surg 2006;32:60-6. [II+]
- Lee P, Smith JP, Kington R. The relationship of self-rated vision and hearing to functional status and well-being among seniors 70 years and older. Am J Ophthalmol 1999;127:447-52. [II++]
- Lee PP, Spritzer K, Hays RD. The impact of blurred vision on functioning and well-being. Ophthalmology 1997;104:390-6. [II++]
- Lundstrom M, Fregell G, Sjoblom A. Vision related daily life problems in patients waiting for a cataract extraction. Br J Ophthalmol 1994;78:608-11. [II-]
- Broman AT, Munoz B, Rodriguez J, et al. The impact of visual impairment and eye disease on vision-related quality of life in a Mexican-American population: proyecto VER. Invest Ophthalmol Vis Sci 2002;43:3393-8. [II++]
- Tinetti ME, Speechley M, Ginter SF. Risk factors for falls among elderly persons living in the community. N Engl J Med 1988;319:1701-7. [II++]
- De Coster C, Dik N, Bellan L. Health care utilization for injury in cataract surgery patients. Can J Ophthalmol 2007;42:567-72. [II++]
- Felson DT, Anderson JJ, Hannan MT, et al. Impaired vision and hip fracture. The Framingham Study. J Am Geriatr Soc 1989;37:495-500. [II+]
- Sloane ME, Ball K, Owsley C, et al. The Visual Activities Questionnaire: developing an instrument for assessing problems in everyday visual tasks. Technical Digest, Noninvasive Assessment of the Visual System 1992;1:26-9. [II+]
- Datta S, Foss AJ, Grainge MJ, et al. The importance of acuity, stereopsis, and contrast sensitivity for health-related quality of life in elderly women with cataracts. Invest Ophthalmol Vis Sci 2008;49:1-6. [II++]
- Steinberg EP, Tielsch JM, Schein OD, et al. The VF-14. An index of functional impairment in patients with cataract. Arch Ophthalmol 1994;112:630-8. [II++]
- Bilbao A, Quintana JM, Escobar A, et al. Responsiveness and clinically important differences for the VF-14 index, SF-36, and visual acuity in patients undergoing cataract surgery. Ophthalmology 2009;116:418-24. [II+]
- Lundstrom M, Pesudovs K. Catquest-9SF patient outcomes questionnaire: nine-item short-form Rasch-scaled revision of the Catquest questionnaire. J Cataract Refract Surg 2009;35:504-13. [II++]
- Gothwal VK, Wright TA, Lamoureux EL, Pesudovs K. Visual Activities Questionnaire: assessment of subscale validity for cataract surgery outcomes. J Cataract Refract Surg 2009;35:1961-9. [II+]
- Cutler DM, McClellan M. Is technological change in medicine worth it? Health Aff (Millwood) 2001;20:11-29. [II++]
- Quintana JM, Arostegui I, Alberdi T, et al, IRYSS-Cataract Group. Decision trees for indication of cataract surgery based on changes in visual acuity. Ophthalmology 2010;117:1471-8. [II+]
- Charalampidou S, Loughman J, Nolan J, et al. Prognostic indicators and outcome measures for surgical removal of symptomatic nonadvanced cataract. Arch Ophthalmol 2011;129:1155-61. [II-]
- Schein OD, Steinberg EP, Cassard SD, et al. Predictors of outcome in patients who underwent cataract surgery. Ophthalmology 1995;102:817-23. [II+]
- Mangione CM, Phillips RS, Seddon JM, et al. Development of the 'Activities of Daily Vision Scale'. A measure of visual functional status. Med Care 1992;30:1111-26. [II+]
- Cassard SD, Patrick DL, Damiano AM, et al. Reproducibility and responsiveness of the VF-14. An index of functional impairment in patients with cataracts. Arch Ophthalmol 1995;113:1508-13. [II+]
- Rosen PN, Kaplan RM, David K. Measuring outcomes of cataract surgery using the Quality of Well-Being Scale and VF-14 Visual Function Index. J Cataract Refract Surg 2005;31:369-78. [II-]
- Tobacman JK, Lee P, Zimmerman B, et al. Assessment of appropriateness of cataract surgery at ten academic medical centers in 1990. Ophthalmology 1996;103:207-15. [II+]
- Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. J Cataract Refract Surg 2005;31:664-73. [II-]
- Chang DF, Braga-Mele R, Mamalis N, et al, ASCRS Cataract Clinical Committee. ASCRS White Paper: clinical review of intraoperative floppy-iris syndrome. J Cataract Refract Surg 2008;34:2153-62. [review article; not rated]
- Chang DF, Osher RH, Wang L, Koch DD. Prospective multicenter evaluation of cataract surgery in patients taking tamsulosin (Flomax). Ophthalmology 2007;114:957-64. [II+]
- Chang DF, Braga-Mele R, Mamalis N, et al, ASCRS Cataract Clinical Committee. Clinical experience with intraoperative floppy-iris syndrome. Results of the 2008 ASCRS member survey. J Cataract Refract Surg 2008;34:1201-9. [III]
- Bell CM, Hatch WV, Fischer HD, et al. Association between tamsulosin and serious ophthalmic adverse events in older men following cataract surgery. JAMA 2009;301:1991-6. [II++]
- Chatziralli IP, Sergentanis TN. Risk factors for intraoperative floppy iris syndrome: a meta-analysis. Ophthalmology 2011;118:730-5. [II++]
- Shingleton BJ, Gamell LS, O'Donoghue MW, et al. Long-term changes in intraocular pressure after clear corneal phacoemulsification: normal patients versus glaucoma suspect and glaucoma patients. J Cataract Refract Surg 1999;25:885-90. [III]
- Tennen DG, Masket S. Short-and long-term effect of clear corneal incisions on intraocular pressure. J Cataract Refract Surg 1996;22:568-70. [III]
- Tong JT, Miller KM. Intraocular pressure change after sutureless phacoemulsification and foldable posterior chamber lens implantation. J Cataract Refract Surg 1998;24:256-62. [II+]
- Poley BJ, Lindstrom RL, Samuelson TW, Schulze R Jr. Intraocular pressure reduction after phacoemulsification with intraocular lens implantation in glaucomatous and nonglaucomatous eyes: evaluation of a causal relationship between the natural lens and open-angle glaucoma. J Cataract Refract Surg 2009;35:1946-55. [II-]
- Vizzeri G, Weinreb RN. Cataract surgery and glaucoma. Curr Opin Ophthalmol 2010;21:20-4. [review article; not rated]
- Shrivastava A, Singh K. The effect of cataract extraction on intraocular pressure. Curr Opin Ophthalmol 2010;21:118-22. [review article; not rated]
- Hayashi K, Hayashi H, Nakao F, Hayashi F. Effect of cataract surgery on intraocular pressure control in glaucoma patients. J Cataract Refract Surg 2001;27:1779-86. [II-]
- Friedman DS, Jampel HD, Lubomski LH, et al. Surgical strategies for coexisting glaucoma and cataract: an evidence-based update. Ophthalmology 2002;109:1902-13. [II++]
- Endophthalmitis Vitrectomy Study Group. Results of the Endophthalmitis Vitrectomy Study. A randomized trial of immediate vitrectomy and of intravenous antibiotics for the treatment of postoperative bacterial endophthalmitis. Arch Ophthalmol 1995;113:1479-96. [I+]
- Mollan SP, Gao A, Lockwood A, et al. Postcataract endophthalmitis: incidence and microbial isolates in a United Kingdom region from 1996 through 2004. J Cataract Refract Surg 2007;33:265-8. [III]
- Wejde G, Montan P, Lundstrom M, et al. Endophthalmitis following cataract surgery in Sweden: national prospective survey 1999-2001. Acta Ophthalmol Scand 2005;83:7-10. [II+]
- Deramo VA, Lai JC, Fastenberg DM, Udell IJ. Acute endophthalmitis in eyes treated prophylactically with gatifloxacin and moxifloxacin. Am J Ophthalmol 2006;142:721-5. [II+]
- Deramo VA, Lai JC, Winokur J, et al. Visual outcome and bacterial sensitivity after methicillin-resistant Staphylococcus aureus-associated acute endophthalmitis. Am J Ophthalmol 2008;145:413-7. [III]
- Recchia FM, Busbee BG, Pearlman RB, et al. Changing trends in the microbiologic aspects of postcataract endophthalmitis. Arch Ophthalmol 2005;123:341-6. [III]
- Altan T, Acar N, Kapran Z, et al. Acute-onset endophthalmitis after cataract surgery: success of initial therapy, visual outcomes, and related factors. Retina 2009;29:606-12. [III]
- Olson R, Donnenfeld E, Bucci FA, et al. Methicillin resistance of Staphylococcus species among health care and nonhealth care workers undergoing cataract surgery. Clin Ophthalmol 2010;4:1505-14. [III]
- Murphy CC, Nicholson S, Quah SA, et al. Pharmacokinetics of vancomycin following intracameral bolus injection in patients undergoing phacoemulsification cataract surgery. Br J Ophthalmol 2007;91:1350-3. [II++]
- Barry P, Seal DV, Gettinby G, et al. ESCRS study of prophylaxis of postoperative endophthalmitis after cataract surgery: preliminary report of principal results from a European multicenter study. J Cataract Refract Surg 2006;32:407-10. [I-]
- Lundstrom M, Wejde G, Stenevi U, et al. Endophthalmitis after cataract surgery: a nationwide prospective study evaluating incidence in relation to incision type and location. Ophthalmology 2007;114:866-70. [II+]
- Montan P, Lundstrom M, Stenevi U, Thorburn W. Endophthalmitis following cataract surgery in Sweden. The 1998 national prospective survey. Acta Ophthalmol Scand 2002;80:258-61. [III]
- Jensen MK, Fiscella RG, Crandall AS, et al. A retrospective study of endophtalmitis rates comparing quinolone antibiotics. Am J Ophthalmol 2005;139:141-8. [II+]
- Jensen MK, Fiscella RG, Moshirfar M, Mooney B. Third- and fourth-generation fluoroquinolones: retrospective comparison of endophthalmitis after cataract surgery performed over 10 years. J Cataract Refract Surg 2008;34:1460-7. [II+]
- Lloyd JC, Braga-Mele R. Incidence of postoperative endophthalmitis in a high-volume cataract surgicentre in Canada. Can J Ophthalmol 2009;44:288-92. [III]
- Thoms SS, Musch DC, Soong HK. Postoperative endophthalmitis associated with sutured versus unsutured clear corneal cataract incisions. Br J Ophthalmol 2007;91:728-30. [III]
- Wallin T, Parker J, Jin Y, et al. Cohort study of 27 cases of endophthalmitis at a single institution. J Cataract Refract Surg 2005;31:735-41. [II-]
- Ng JQ, Morlet N, Bulsara MK, Semmens JB. Reducing the risk for endophthalmitis after cataract surgery: population-based nested case-control study: endophthalmitis population study of Western Australia sixth report. J Cataract Refract Surg 2007;33:269-80. [II+]
- Sengupta S, Chang DF, Gandhi R, et al. Incidence and long-term outcomes of toxic anterior segment syndrome at Aravind Eye Hospital. J Cataract Refract Surg 2011;37:1673-8. [III]
- Cutler Peck CM, Brubaker J, Clouser S, et al. Toxic anterior segment syndrome: common causes. J Cataract Refract Surg 2010;36:1073-80. [III]
- Chang DF, Masket S, Miller KM, et al, ASCRS Cataract Clinical Committee. Complications of sulcus placement of single-piece acrylic intraocular lenses: recommendations for backup IOL implantation following posterior capsule rupture. J Cataract Refract Surg 2009;35:1445-58. [III]
- Kusaka S, Kodama T, Ohashi Y. Condensation of silicone oil on the posterior surface of a silicone intraocular lens during vitrectomy. Am J Ophthalmol 1996;121:574-5. [III]
- Porter RG, Peters JD, Bourke RD. De-misting condensation on intraocular lenses. Ophthalmology 2000;107:778-82. [III]
- Suto C. Sliding scale of IOL power for sulcus fixation using computer simulation. J Cataract Refract Surg 2004;30:2452-4. [computer simulation; not rated]
- Bayramlar H, Hepsen IF, Yilmaz H. Myopic shift from the predicted refraction after sulcus fixation of PMMA posterior chamber intraocular lenses. Can J Ophthalmol 2006;41:78-82. [III]
- Gimbel HV, DeBroff BM. Intraocular lens optic capture. J Cataract Refract Surg 2004;30:200-6. [III]
- Altmann GE, Nichamin LD, Lane SS, Pepose JS. Optical performance of 3 intraocular lens designs in the presence of decentration. J Cataract Refract Surg 2005;31:574-85. [experimental study; not rated]
- Wang L, Koch DD. Effect of decentration of wavefront-corrected intraocular lenses on the higher-order aberrations of the eye. Arch Ophthalmol 2005;123:1226-30. [experimental study; not rated]
- American Academy of Ophthalmology Wrong-Site Task Force. Patient Safety Bulletin. Recommendations of American Academy of Ophthalmology Wrong-Site Task Force. San Francisco, CA: American Academy of Ophthalmology; 2008. Available at: http://one.aao.org/CE/PracticeGuidelines/Patient.aspx. [position paper; not rated]
- de Vries EN, Prins HA, Crolla RM, et al. Effect of a comprehensive surgical safety system on patient outcomes. N Engl J Med 2010;363:1928-37. [II+]
- Kelly SP, Jalil A. Wrong intraocular lens implant; learning from reported patient safety incidents. Eye (Lond) 2011;25:730-4. [III]
- Stahel PF, Sabel AL, Victoroff MS, et al. Wrong-site and wrong-patient procedures in the universal protocol era: analysis of a prospective database of physician self-reported occurrences. Arch Surg 2010;145:978-84. [II-]
- Pennsylvania Patient Safety Authority. The evidence base for the principles for reliable performance of the Universal Protocol. 2010. Available at: www.patientsafetyauthority.org/EducationalTools/PatientSafetyTools/PWSS/Documents/u_principles.pdf. Accessed July 20, 2011. [III]
- Pennsylvania Patient Safety Authority. Quarterly update: the evidence base for best practices for preventing wrong-site surgery. Pa Patient Saf Advis [online]. Dec 2010. Available at: www.patientsafetyauthority.org/ADVISORIES/AdvisoryLibrary/2010/Dec7%284%29/Pages/151.aspx. Accessed July 20, 2011. [III]
- Congdon N, Vingerling JR, Klein BE, et al. Prevalence of cataract and pseudophakia/aphakia among adults in the United States. Arch Ophthalmol 2004;122:487-94.
- Cotter SA, Varma R, Ying-Lai M, et al. Causes of low vision and blindness in adult Latinos: the Los Angeles Latino Eye Study. Ophthalmology 2006;113:1574-82.
- Vivino MA, Chintalagiri S, Trus B, Datiles M. Development of a Scheimpflug slit lamp camera system for quantitative densitometric analysis. Eye 1993;7 (Pt 6):791-8.
- Magno BV, Freidlin V, Datiles MB III. Reproducibility of the NEI Scheimpflug Cataract Imaging System. Invest Ophthalmol Vis Sci 1994;35:3078-84.
- Chylack LT Jr, Wolfe JK, Singer DM, et al. The Lens Opacities Classification System III. The Longitudinal Study of Cataract Study Group. Arch Ophthalmol 1993;111:831-6.
- Taylor HR, West SK. The clinical grading of lens opacities. Aust N Z J Ophthalmol 1989;17:81-6.
- Klein BE, Klein R, Linton KL, et al. Assessment of cataracts from photographs in the Beaver Dam Eye Study. Ophthalmology 1990;97:1428-33.
- Ventura L, Lam KW, Lin TY. The differences between brunescent and opalescent nucleosclerosis. Lens Research 1987;4:79-86.
- Klein BE, Klein R, Moss SE. Incident cataract surgery: the Beaver Dam Eye Study. Ophthalmology 1997;104:573-80.
- Panchapakesan J, Mitchell P, Tumuluri K, et al. Five year incidence of cataract surgery: the Blue Mountains Eye Study. Br J Ophthalmol 2003;87:168-72.
- Lewis A, Congdon N, Munoz B, et al. Cataract surgery and subtype in a defined, older population: the SEECAT Project. Br J Ophthalmol 2004;88:1512-7.
- Prevent Blindness America. Vision problems in the U.S.: prevalence of adult vision impairment and age-related eye disease in America. 2008 update to the fourth edition. Chicago, IL: Prevent Blindness America;2008:23. Available at: www.preventblindness.net/site/DocServer/VPUS_2008_update.pdf?docID=1561. Accessed August 11, 2011.
- West SK, Munoz B, Schein OD, et al. Racial differences in lens opacities: the Salisbury Eye Evaluation (SEE) Project. Am J Epidemiol 1998;148:1033-9.
- Varma R, Torres M. Prevalence of lens opacities in Latinos: the Los Angeles Latino Eye Study. Ophthalmology 2004;111:1449-56.
- West SK, Valmadrid CT. Epidemiology of risk factors for age-related cataract. Surv Ophthalmol 1995;39:323-34.
- Cumming RG, Mitchell P, Leeder SR. Use of inhaled corticosteroids and the risk of cataracts. N Engl J Med 1997;337:8-14.
- Jick SS, Vasilakis-Scaramozza C, Maier WC. The risk of cataract among users of inhaled steroids. Epidemiology 2001;12:229-34.
- Klein BE, Klein R, Lee KE, Danforth LG. Drug use and five-year incidence of age-related cataracts: The Beaver Dam Eye Study. Ophthalmology 2001;108:1670-4.
- Smeeth L, Boulis M, Hubbard R, Fletcher AE. A population based case-control study of cataract and inhaled corticosteroids. Br J Ophthalmol 2003;87:1247-51.
- Urban RC Jr, Cotlier E. Corticosteroid-induced cataracts. Surv Ophthalmol 1986;31:102-10.
- Hennis A, Wu SY, Nemesure B, Leske MC. Risk factors for incident cortical and posterior subcapsular lens opacities in the Barbados Eye Studies. Arch Ophthalmol 2004;122:525-30.
- Klein BE, Klein R, Lee KE. Diabetes, cardiovascular disease, selected cardiovascular disease risk factors, and the 5-year incidence of age-related cataract and progression of lens opacities: the Beaver Dam Eye Study. Am J Ophthalmol 1998;126:782-90.
- Leske MC, Wu SY, Hennis A, et al. Diabetes, hypertension, and central obesity as cataract risk factors in a black population. The Barbados Eye Study. Ophthalmology 1999;106:35-41.
- Belkacemi Y, Labopin M, Vernant JP, et al. Cataracts after total body irradiation and bone marrow transplantation in patients with acute leukemia in complete remission: a study of the European Group for Blood and Marrow Transplantation. Int J Radiat Oncol Biol Phys 1998;41:659-68.
- Ainsbury EA, Bouffler SD, Dorr W, et al. Radiation cataractogenesis: a review of recent studies. Radiat Res 2009;172:1-9.
- Hamon MD, Gale RF, Macdonald ID, et al. Incidence of cataracts after single fraction total body irradiation: the role of steroids and graft versus host disease. Bone Marrow Transplant 1993;12:233-6.
- Pardo-Munoz A, Muriel-Herrero A, Abraira V, et al. Phacoemulsification in previously vitrectomized patients: an analysis of the surgical results in 100 eyes as well as the factors contributing to the cataract formation. Eur J Ophthalmol 2006;16:52-9.
- Asbell PA, Dualan I, Mindel J, et al. Age-related cataract. Lancet 2005;365:599-609.
- Leske MC, Wu SY, Nemesure B, et al. Nine-year incidence of lens opacities in the Barbados Eye Studies. Ophthalmology 2004;111:483-90.
- McCarty CA, Mukesh BN, Dimitrov PN, Taylor HR. Incidence and progression of cataract in the Melbourne Visual Impairment Project. Am J Ophthalmol 2003;136:10-7.
- Leske MC, Chylack LT Jr, He Q, et al. Incidence and progression of cortical and posterior subcapsular opacities: the Longitudinal Study of Cataract. The LSC Group. Ophthalmology 1997;104:1987-93.
- Leske MC, Chylack LT Jr, Wu SY, et al. Incidence and progression of nuclear opacities in the Longitudinal Study of Cataract. Ophthalmology 1996;103:705-12.
- Kelly SP, Thornton J, Edwards R, et al. Smoking and cataract: review of causal association. J Cataract Refract Surg 2005;31:2395-404.
- West S, Munoz B, Emmett EA, Taylor HR. Cigarette smoking and risk of nuclear cataracts. Arch Ophthalmol 1989;107:1166-9.
- Christen WG, Manson JE, Seddon JM, et al. A prospective study of cigarette smoking and risk of cataract in men. JAMA 1992;268:989-93.
- Christen WG, Glynn RJ, Ajani UA, et al. Smoking cessation and risk of age-related cataract in men. JAMA 2000;284:713-6.
- Leske MC, Chylack LT Jr, He Q, et al. Risk factors for nuclear opalescence in a longitudinal study. LSC Group. Longitudinal Study of Cataract. Am J Epidemiol 1998;147:36-41.
- Mukesh BN, Le A, Dimitrov PN, et al. Development of cataract and associated risk factors: the Visual Impairment Project. Arch Ophthalmol 2006;124:79-85.
- Hankinson SE, Willett WC, Colditz GA, et al. A prospective study of cigarette smoking and risk of cataract surgery in women. JAMA 1992;268:994-8.
- Klein BE, Klein R, Linton KL, Franke T. Cigarette smoking and lens opacities: the Beaver Dam Eye Study. Am J Prev Med 1993;9:27-30.
- Leske MC, Chylack LT Jr, Wu SY. The Lens Opacities Case-Control Study. Risk factors for cataract. Arch Ophthalmol 1991;109:244-51.
- Lindblad BE, Hakansson N, Svensson H, et al. Intensity of smoking and smoking cessation in relation to risk of cataract extraction: a prospective study of women. Am J Epidemiol 2005;162:73-9.
- Weintraub JM, Willett WC, Rosner B, et al. Smoking cessation and risk of cataract extraction among US women and men. Am J Epidemiol 2002;155:72-9.
- Delcourt C, Carriere I, Ponton-Sanchez A, et al, POLA Study Group. Light exposure and the risk of cortical, nuclear, and posterior subcapsular cataracts: the Pathologies Oculaires Liees a l'Age (POLA) study. Arch Ophthalmol 2000;118:385-92.
- McCarty CA, Mukesh BN, Fu CL, Taylor HR. The epidemiology of cataract in Australia. Am J Ophthalmol 1999;128:446-65.
- Taylor HR, West SK, Rosenthal FS, et al. Effect of ultraviolet radiation on cataract formation. N Engl J Med 1988;319:1429-33.
- West SK, Duncan DD, Munoz B, et al. Sunlight exposure and risk of lens opacities in a population-based study: the Salisbury Eye Evaluation Project. JAMA 1998;280:714-8.
- Neale RE, Purdie JL, Hirst LW, Green AC. Sun exposure as a risk factor for nuclear cataract. Epidemiology 2003;14:707-12.
- McCarty CA, Taylor HR. A review of the epidemiologic evidence linking ultraviolet radiation and cataracts. Dev Ophthalmol 2002;35:21-31.
- McCarty CA, Nanjan MB, Taylor HR. Attributable risk estimates for cataract to prioritize medical and public health action. Invest Ophthalmol Vis Sci 2000;41:3720-5.
- Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E and beta carotene for age-related cataract and vision loss: AREDS report no. 9. Arch Ophthalmol 2001;119:1439-52.
- Christen W, Glynn R, Sperduto R, et al. Age-related cataract in a randomized trial of beta-carotene in women. Ophthalmic Epidemiol 2004;11:401-12.
- Christen WG, Manson JE, Glynn RJ, et al. A randomized trial of beta carotene and age-related cataract in US physicians. Arch Ophthalmol 2003;121:372-8.
- Gritz DC, Srinivasan M, Smith SD, et al. The Antioxidants in Prevention of Cataracts Study: effects of antioxidant supplements on cataract progression in South India. Br J Ophthalmol 2006;90:847-51.
- McNeil JJ, Robman L, Tikellis G, et al. Vitamin E supplementation and cataract: randomized controlled trial. Ophthalmology 2004;111:75-84.
- Teikari JM, Virtamo J, Rautalahti M, et al. Long-term supplementation with alpha-tocopherol and beta-carotene and age-related cataract. Acta Ophthalmol Scand 1997;75:634-40.
- Christen WG, Glynn RJ, Chew EY, Buring JE. Vitamin E and age-related cataract in a randomized trial of women. Ophthalmology 2008;115:822-9.
- Christen WG, Glynn RJ, Sesso HD, et al. Age-related cataract in a randomized trial of vitamins E and C in men. Arch Ophthalmol 2010;128:1397-405.
- Huang HY, Caballero B, Chang S, et al. Multivitamin/Mineral Supplements and Prevention of Chronic Disease. Evidence Report/Technology Assessment No. 139. (Prepared by The Johns Hopkins University Evidence-Based Practice Center under Contract No. 290-02-0018.) AHRQ Publication No. 06-E012. Rockville, MD: Agency for Healthcare Research and Quality. May 2006.
- Chylack LT Jr, Brown NP, Bron A, et al. The Roche European American Cataract Trial (REACT): a randomized clinical trial to investigate the efficacy of an oral antioxidant micronutrient mixture to slow progression of age-related cataract. Ophthalmic Epidemiol 2002;9:49-80.
- Maraini G, Sperduto RD, Ferris F, et al, Clinical Trial of Nutritional Supplements and Age-Related Cataract Study Group. A randomized, double-masked, placebo-controlled clinical trial of multivitamin supplementation for age-related lens opacities: Clinical Trial of Nutritional Supplements and Age-Related Cataract report no. 3. Ophthalmology 2008;115:599-607.
- Sperduto RD, Hu TS, Milton RC, et al. The Linxian cataract studies. Two nutrition intervention trials. Arch Ophthalmol 1993;111:1246-53.
- Peto R, Gray R, Collins R, et al. Randomised trial of prophylactic daily aspirin in British male doctors. Br Med J (Clin Res Ed) 1988;296:313-6.
- Chew EY, Williams GA, Burton TC, et al. Aspirin effects on the development of cataracts in patients with diabetes mellitus. Early Treatment Diabetic Retinopathy Study report number 16. Arch Ophthalmol 1992;110:339-42.
- Seddon JM, Christen WG, Manson JE, et al. Low-dose aspirin and risks of cataract in a randomized trial of US physicians. Arch Ophthalmol 1991;109:252-5.
- Christen WG, Manson JE, Glynn RJ, et al. Low-dose aspirin and risk of cataract and subtypes in a randomized trial of U.S. physicians. Ophthalmic Epidemiol 1998;5:133-42.
- Christen WG, Ajani UA, Schaumberg DA, et al. Aspirin use and risk of cataract in posttrial follow-up of Physicians' Health Study I. Arch Ophthalmol 2001;119:405-12.
- Ernst P, Baltzan M, Deschenes J, Suissa S. Low-dose inhaled and nasal corticosteroid use and the risk of cataracts. Eur Respir J 2006;27:1168-74.
- Garbe E, Suissa S, LeLorier J. Association of inhaled corticosteroid use with cataract extraction in elderly patients. JAMA 1998;280:539-43.
- Hammond CJ, Duncan DD, Snieder H, et al. The heritability of age-related cortical cataract: the twin eye study. Invest Ophthalmol Vis Sci 2001;42:601-5.
- Heiba IM, Elston RC, Klein BE, Klein R. Evidence for a major gene for cortical cataract. Invest Ophthalmol Vis Sci 1995;36:227-35.
- Familial aggregation of lens opacities: the Framingham Eye Study and the Framingham Offspring Eye Study. Am J Epidemiol 1994;140:555-64.
- Congdon N, Broman KW, Lai H, et al. Cortical, but not posterior subcapsular, cataract shows significant familial aggregation in an older population after adjustment for possible shared environmental factors. Ophthalmology 2005;112:73-7.
- Younan C, Mitchell P, Cumming R, et al. Cardiovascular disease, vascular risk factors and the incidence of cataract and cataract surgery: the Blue Mountains Eye Study. Ophthalmic Epidemiol 2003;10:227-40.
- Hammond CJ, Snieder H, Spector TD, Gilbert CE. Genetic and environmental factors in age-related nuclear cataracts in monozygotic and dizygotic twins. N Engl J Med 2000;342:1786-90.
- Heiba IM, Elston RC, Klein BE, Klein R. Genetic etiology of nuclear cataract: evidence for a major gene. Am J Med Genet 1993;47:1208-14.
- Kanthan GL, Wang JJ, Rochtchina E, Mitchell P. Use of antihypertensive medications and topical beta-blockers and the long-term incidence of cataract and cataract surgery. Br J Ophthalmol 2009;93:1210-4.
- Klein AP, Duggal P, Lee KE, et al. Polygenic effects and cigarette smoking account for a portion of the familial aggregation of nuclear sclerosis. Am J Epidemiol 2005;161:707-13.
- Age-Related Eye Disease Study Research Group. Risk factors associated with age-related nuclear and cortical cataract: a case-control study in the Age-Related Eye Disease Study: AREDS report no. 5. Ophthalmology 2001;108:1400-8.
- Wong TY, Klein BE, Klein R, Tomany SC. Relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataracts: the Beaver Dam Eye Study. Br J Ophthalmol 2002;86:152-5.
- Fishman GA, Anderson RJ, Lourenco P. Prevalence of posterior subcapsular lens opacities in patients with retinitis pigmentosa. Br J Ophthalmol 1985;69:263-6.
- Pruett RC. Retinitis pigmentosa: clinical observations and correlations. Trans Am Ophthalmol Soc 1983;81:693-735.
- Heckenlively J. The frequency of posterior subcapsular cataract in the hereditary retinal degenerations. Am J Ophthalmol 1982;93:733-8.
- Giuffre G, Dardanoni G, Lodato G. A case-control study on risk factors for nuclear, cortical and posterior subcapsular cataract: the Casteldaccia Eye Study. Acta Ophthalmol Scand 2005;83:567-73.
- Raju P, George R, Ve Ramesh S, et al. Influence of tobacco use on cataract development. Br J Ophthalmol 2006;90:1374-7.
- Fernandez MM, Afshari NA. Nutrition and the prevention of cataracts. Curr Opin Ophthalmol 2008;19:66-70.
- Hippisley-Cox J, Coupland C. Unintended effects of statins in men and women in England and Wales: population based cohort study using the QResearch database. BMJ 2010;340:c2197.
- Klein BE, Klein R, Lee KE, Grady LM. Statin use and incident nuclear cataract. JAMA 2006;295:2752-8.
- Tan JS, Mitchell P, Rochtchina E, Wang JJ. Statin use and the long-term risk of incident cataract: the Blue Mountains Eye Study. Am J Ophthalmol 2007;143:687-9.
- Salive ME, Guralnik J, Glynn RJ, et al. Association of visual impairment with mobility and physical function. J Am Geriatr Soc 1994;42:287-92.
- Foss AJ, Harwood RH, Osborn F, et al. Falls and health status in elderly women following second eye cataract surgery: a randomised controlled trial. Age Ageing 2006;35:66-71.
- Laforge RG, Spector WD, Sternberg J. The relationship of vision and hearing impairment to one-year mortality and functional decline. J Aging Health 1992;4:126-48.
- Klein BE, Klein R, Knudtson MD. Lens opacities associated with performance-based and self-assessed visual functions. Ophthalmology 2006;113:1257-63.
- Chandrasekaran S, Wang JJ, Rochtchina E, Mitchell P. Change in health-related quality of life after cataract surgery in a population-based sample. Eye (Lond) 2008;22:479-84.
- Asplund R, Ejdervik Lindblad B. The development of sleep in persons undergoing cataract surgery. Arch Gerontol Geriatr 2002;35:179-87.
- Asplund R, Lindblad BE. Sleep and sleepiness 1 and 9 months after cataract surgery. Arch Gerontol Geriatr 2004;38:69-75.
- Cummings SR, Nevitt MC, Browner WS, et al. Risk factors for hip fracture in white women. Study of Osteoporotic Fractures Research Group. N Engl J Med 1995;332:767-73.
- Wang JJ, Mitchell P, Cumming RG, Smith W. Visual impairment and nursing home placement in older Australians: the Blue Mountains Eye Study. Ophthalmic Epidemiol 2003;10:3-13.
- McGwin G Jr, Chapman V, Owsley C. Visual risk factors for driving difficulty among older drivers. Accid Anal Prev 2000;32:735-44.
- Owsley C, Stalvey BT, Wells J, et al. Visual risk factors for crash involvement in older drivers with cataract. Arch Ophthalmol 2001;119:881-7.
- Subzwari S, Desapriya E, Scime G, et al. Effectiveness of cataract surgery in reducing driving-related difficulties: a systematic review and meta-analysis. Inj Prev 2008;14:324-8.
- Wood JM, Carberry TP. Bilateral cataract surgery and driving performance. Br J Ophthalmol 2006;90:1277-80.
- Owsley C, Stalvey B, Wells J, Sloane ME. Older drivers and cataract: driving habits and crash risk. J Gerontol A Biol Sci Med Sci 1999;54:M203-11.
- Owsley C, McGwin G, Jr, Sloane M, et al. Impact of cataract surgery on motor vehicle crash involvement by older adults. JAMA 2002;288:841-9.
- Bassett K, Noertjojo K, Nirmalan P, et al. RESIO revisited: visual function assessment and cataract surgery in British Columbia. Can J Ophthalmol 2005;40:27-33.
- Rocha KM, Nose W, Bottos K, et al. Higher-order aberrations of age-related cataract. J Cataract Refract Surg 2007;33:1442-6.
- Sachdev N, Ormonde SE, Sherwin T, McGhee CN. Higher-order aberrations of lenticular opacities. J Cataract Refract Surg 2004;30:1642-8.
- Ware JE Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Med Care 1992;30:473-83.
- Bergner M, Bobbitt RA, Carter WB, Gilson BS. The Sickness Impact Profile: development and final revision of a health status measure. Med Care 1981;19:787-805.
- Damiano AM, Steinberg EP, Cassard SD, et al. Comparison of generic versus disease-specific measures of functional impairment in patients with cataract. Med Care 1995;33:AS120-30.
- Bernth-Petersen P. Visual functioning in cataract patients. Methods of measuring and results. Acta Ophthalmol (Copenh) 1981;59:198-205.
- Gothwal VK, Wright TA, Lamoureux EL, Pesudovs K. Measuring outcomes of cataract surgery using the Visual Function Index-14. J Cataract Refract Surg 2010;36:1181-8.
- Mangione CM, Lee PP, Gutierrez PR, et al. Development of the 25-item National Eye Institute Visual Function Questionnaire. Arch Ophthalmol 2001;119:1050-8.
- Clemons TE, Chew EY, Bressler SB, McBee W. National Eye Institute Visual Function Questionnaire in the Age-Related Eye Disease Study (AREDS): AREDS report no. 10. Arch Ophthalmol 2003;121:211-7.
- Bellan L. Why are patients with no visual symptoms on cataract waiting lists? Can J Ophthalmol 2005;40:433-8.
- American Academy of Ophthalmology Preferred Practice Patterns Committee. Preferred Practice Pattern® Guidelines. Comprehensive Adult Medical Eye Evaluation. San Francisco, CA: American Academy of Ophthalmology; 2010. Available at: www.aao.org/ppp.
- Adamsons I, Rubin GS, Vitale S, et al. The effect of early cataracts on glare and contrast sensitivity. A pilot study. Arch Ophthalmol 1992;110:1081-6.
- Rubin GS, Adamsons IA, Stark WJ. Comparison of acuity, contrast sensitivity, and disability glare before and after cataract surgery. Arch Ophthalmol 1993;111:56-61.
- Holladay JT, Prager TC, Trujillo J, Ruiz RS. Brightness acuity test and outdoor visual acuity in cataract patients. J Cataract Refract Surg 1987;13:67-9.
- Prager TC, Urso RG, Holladay JT, Stewart RH. Glare testing in cataract patients: instrument evaluation and identification of sources of methodological error. J Cataract Refract Surg 1989;15:149-57.
- Yamaguchi T, Negishi K, Tsubota K. Functional visual acuity measurement in cataract and intraocular lens implantation. Curr Opin Ophthalmol 2011;22:31-6.
- Pfoff DS, Werner JS. Effect of cataract surgery on contrast sensitivity and glare in patients with 20/50 or better Snellen acuity. J Cataract Refract Surg 1994;20:620-5.
- Adamsons IA, Vitale S, Stark WJ, Rubin GS. The association of postoperative subjective visual function with acuity, glare, and contrast sensitivity in patients with early cataract. Arch Ophthalmol 1996;114:529-36.
- Elliott DB, Bullimore MA. Assessing the reliability, discriminative ability, and validity of disability glare tests. Invest Ophthalmol Vis Sci 1993;34:108-19.
- Wang L, Santaella RM, Booth M, Koch DD. Higher-order aberrations from the internal optics of the eye. J Cataract Refract Surg 2005;31:1512-9.
- Beiko GH. Personalized correction of spherical aberration in cataract surgery. J Cataract Refract Surg 2007;33:1455-60.
- Melki SA, Safar A, Martin J, et al. Potential acuity pinhole: a simple method to measure potential visual acuity in patients with cataracts, comparison to potential acuity meter. Ophthalmology 1999;106:1262-7.
- Gus PI, Kwitko I, Roehe D, Kwitko S. Potential acuity meter accuracy in cataract patients. J Cataract Refract Surg 2000;26:1238-41.
- Tetz MR, Klein U, Volcker HE. Measurement of potential visual acuity in 343 patients with cataracts. A prospective clinical study. Ger J Ophthalmol 1992;1:403-8.
- Lasa MS, Datiles MB III, Freidlin V. Potential vision tests in patients with cataracts. Ophthalmology 1995;102:1007-11.
- Hofeldt AJ, Weiss MJ. Illuminated near card assessment of potential acuity in eyes with cataract. Ophthalmology 1998;105:1531-6.
- Cuzzani OE, Ellant JP, Young PW, et al. Potential acuity meter versus scanning laser ophthalmoscope to predict visual acuity in cataract patients. J Cataract Refract Surg 1998;24:263-9.
- Chang MA, Airiani S, Miele D, Braunstein RE. A comparison of the potential acuity meter (PAM) and the illuminated near card (INC) in patients undergoing phacoemulsification. Eye (Lond) 2006;20:1345-51.
- Vryghem JC, Van Cleynenbreugel H, Van Calster J, Leroux K. Predicting cataract surgery results using a macular function test. J Cataract Refract Surg 2004;30:2349-53.
- Bourne WM, Nelson LR, Hodge DO. Continued endothelial cell loss ten years after lens implantation. Ophthalmology 1994;101:1014-22; discussion 1022-3.
- Bates AK, Cheng H. Bullous keratopathy: a study of endothelial cell morphology in patients undergoing cataract surgery. Br J Ophthalmol 1988;72:409-12.
- Safran SG. How spectral-domain OCT has changed my practice. Cataract & Refractive Surgery Today 2010. Available at: http://bmctoday.net/crstoday/pdfs/crst0310_cs_safran.pdf. Accessed May 4, 2011.
- Safran SG. SD-OCT: a quantam leap for anterior segment surgeons. Current Insight. San Francisco, CA: American Academy of Ophthalmology; 2009. Available at: http://one.aao.org/CE/NEWS/CurrentInsight/Archive.aspx. Accessed May 4, 2011.
- National Cancer Institute. Tobacco and the clinician: interventions for medical and dental practice. Monograph #5 (Publ #M492). Bethesda, MD: National Cancer Institute, 1994;1-22.
- Ockene JK. Smoking intervention: the expanding role of the physician. Am J Public Health 1987;77:782-3.
- Pederson LL, Baskerville JC, Wanklin JM. Multivariate statistical models for predicting change in smoking behavior following physician advice to quit smoking. Prev Med 1982;11:536-49.
- Ranney L, Melvin C, Lux L, et al. Tobacco Use: Prevention, Cessation, and Control. Evidence Report/Technology Assessment No. 140. (Prepared by the RTI International -- University of North Carolina Evidence-Based Practice Center under Contract No. 290-02-0016.) AHRQ Publication No. 06-E015. Rockville, MD: Agency for Healthcare Research and Quality. June 2006.
- Wang JJ, Rochtchina E, Tan AG, et al. Use of inhaled and oral corticosteroids and the long-term risk of cataract. Ophthalmology 2009;116:652-7.
- Lagerlund M, Dixon HG, Simpson JA, et al. Observed use of sunglasses in public outdoor settings around Melbourne, Australia: 1993 to 2002. Prev Med 2006;42:291-6.
- American Academy of Ophthalmology. Policy Statement. Pretreatment Assessment: Responsibilities of the Ophthalmologist. San Francisco, CA: American Academy of Ophthalmology; 2006. Available at: http://one.aao.org/CE/PracticeGuidelines/ClinicalStatements.aspx.
- American Academy of Ophthalmology. Policy Statement. An Ophthalmologist's Duties Concerning Postoperative Care. San Francisco, CA: American Academy of Ophthalmology; 2006. Available at: http://one.aao.org/CE/PracticeGuidelines/ClinicalStatements.aspx.
- American Academy of Ophthalmology Committee for Practice Improvement and Ophthalmic Mutual Insurance Company. Patient Safety Bulletin. Practice Guidelines for Informed Consent. San Francisco, CA: American Academy of Ophthalmology; 2010. Available at: http://one.aao.org/CE/PracticeGuidelines/Patient.aspx.
- Lee TH, Marcantonio ER, Mangione CM, et al. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation 1999;100:1043-9.
- Schein OD, Katz J, Bass EB, et al. The value of routine preoperative medical testing before cataract surgery. Study of Medical Testing for Cataract Surgery. N Engl J Med 2000;342:168-75.
- Keay L, Lindsley K, Tielsch J, et al. Routine preoperative medical testing for cataract surgery. Cochrane Database Syst Rev 2009, Issue 2. Art. No.: CD007293. DOI: 10.1002/14651858.CD007293.pub2.
- Findl O, Kriechbaum K, Sacu S, et al. Influence of operator experience on the performance of ultrasound biometry compared to optical biometry before cataract surgery. J Cataract Refract Surg 2003;29:1950-5.
- Shammas HJ. A comparison of immersion and contact techniques for axial length measurement. J Am Intraocul Implant Soc 1984;10:444-7.
- Schelenz J, Kammann J. Comparison of contact and immersion techniques for axial length measurement and implant power calculation. J Cataract Refract Surg 1989;15:425-8.
- Eleftheriadis H. IOLMaster biometry: refractive results of 100 consecutive cases. Br J Ophthalmol 2003;87:960-3.
- Connors R III, Boseman P III, Olson RJ. Accuracy and reproducibility of biometry using partial coherence interferometry. J Cataract Refract Surg 2002;28:235-8.
- Haigis W, Lege B, Miller N, Schneider B. Comparison of immersion ultrasound biometry and partial coherence interferometry for intraocular lens calculation according to Haigis. Graefes Arch Clin Exp Ophthalmol 2000;238:765-73.
- Packer M, Fine IH, Hoffman RS, et al. Immersion A-scan compared with partial coherence interferometry: outcomes analysis. J Cataract Refract Surg 2002;28:239-42.
- Landers J, Goggin M. Comparison of refractive outcomes using immersion ultrasound biometry and IOLMaster biometry. Clin Experiment Ophthalmol 2009;37:566-9.
- Vogel A, Dick HB, Krummenauer F. Reproducibility of optical biometry using partial coherence interferometry: intraobserver and interobserver reliability. J Cataract Refract Surg 2001;27:1961-8.
- Lege BA, Haigis W. Laser interference biometry versus ultrasound biometry in certain clinical conditions. Graefes Arch Clin Exp Ophthalmol 2004;242:8-12.
- Dietlein TS, Roessler G, Luke C, et al. Signal quality of biometry in silicone oil-filled eyes using partial coherence laser interferometry. J Cataract Refract Surg 2005;31:1006-10.
- Hill W, Li W, Koch DD. IOL power calculation in eyes that have undergone LASIK/PRK/RK. Version 3.9. American Society of Cataract and Refractive Surgery. Available at: http://iol.ascrs.org/. Accessed July 8, 2011.
- Hill W, Angeles R, Otani T. Evaluation of a new IOLMaster algorithm to measure axial length. J Cataract Refract Surg 2008;34:920-4.
- Freeman G, Pesudovs K. The impact of cataract severity on measurement acquisition with the IOLMaster. Acta Ophthalmol Scand 2005;83:439-42.
- Tehrani M, Krummenauer F, Blom E, Dick HB. Evaluation of the practicality of optical biometry and applanation ultrasound in 253 eyes. J Cataract Refract Surg 2003;29:741-6.
- Hoffer KJ. The Hoffer Q formula: a comparison of theoretic and regression formulas. J Cataract Refract Surg 1993;19:700-12. Erratum. J Cataract Refract Surg 1994;20:677.
- Zuberbuhler B, Morrell AJ. Errata in printed Hoffer Q formula. J Cataract Refract Surg 2007;33:2; author reply 32-3.
- Hoffer KJ. Clinical results using the Holladay 2 intraocular lens power formula. J Cataract Refract Surg 2000;26:1233-7.
- Olsen T, Corydon L, Gimbel H. Intraocular lens power calculation with an improved anterior chamber depth prediction algorithm. J Cataract Refract Surg 1995;21:313-9.
- Hoffmann PC, Hutz WW, Eckhardt HB. Significance of optic formula selection for postoperative refraction after cataract operation [in German]. Klin Monatsbl Augenheilkd 1997;211:168-77.
- Retzlaff JA, Sanders DR, Kraff MC. Development of the SRK/T intraocular lens implant power calculation formula. J Cataract Refract Surg 1990;16:333-40.
- Haigis W. Intraocular lens calculation in extreme myopia. J Cataract Refract Surg 2009;35:906-11.
- Findl O, Menapace R, Rainer G, Georgopoulos M. Contact zone of piggyback acrylic intraocular lenses. J Cataract Refract Surg 1999;25:860-2.
- Werner L, Shugar JK, Apple DJ, et al. Opacification of piggyback IOLs associated with an amorphous material attached to interlenticular surfaces. J Cataract Refract Surg 2000;26:1612-9.
- Shugar JK, Keeler S. Interpseudophakos intraocular lens surface opacification as a late complication of piggyback acrylic posterior chamber lens implantation. J Cataract Refract Surg 2000;26:448-55.
- Hill WE, Byrne SF. Complex axial length measurements and unusual IOL power calculations. Focal Points: Clinical Modules for Ophthalmologists. Module 9. San Francisco, CA: American Academy of Ophthalmology; 2004:10-11.
- Shugar JK, Lewis C, Lee A. Implantation of multiple foldable acrylic posterior chamber lenses in the capsular bag for high hyperopia. J Cataract Refract Surg 1996;22 Suppl 2:1368-72.
- Gayton JL, Sanders V, Van der Karr M, Raanan MG. Piggybacking intraocular implants to correct pseudophakic refractive error. Ophthalmology 1999;106:56-9.
- Agency for Healthcare Research and Quality. Evidence Report/Technology Assessment: No. 16. Anesthesia management during cataract surgery. Washington, DC: AHRQ Publication No. 00-E015. Rockville, MD: Agency for Healthcare Research and Quality. 2000. Available at: http://archive.ahrq.gov/clinic/epcsums/anestsum.htm. Accessed July 14, 2011.
- Katz J, Feldman MA, Bass EB, et al, The Study of Medical Testing for Cataract Surgery Study Team. Injectable versus topical anesthesia for cataract surgery: patient perceptions of pain and side effects. Ophthalmology 2000;107:2054-60.
- Katz J, Feldman MA, Bass EB, et al. Adverse intraoperative medical events and their association with anesthesia management strategies in cataract surgery. Ophthalmology 2001;108:1721-6.
- Alhassan MB, Kyari F, Ejere HOD. Peribulbar versus retrobulbar anasthesia for cataract surgery. Cochrane Database Syst Rev 2008, Issue 3. Art. No.: CD004083. DOI: 10.1002/14651858.CD004083.pub2.
- Davison M, Padroni S, Bunce C, Rushcen H. Sub-Tenon's anaesthesia versus topical anaesthesia for cataract surgery. Cochrane Database Syst Rev 2007, Issue 3. Art. No.: CD006291. DOI: 10.1002/14651858.CD006291.pub2.
- El-Hindy N, Johnston RL, Jaycock P, et al. The Cataract National Dataset Electronic Multi-centre Audit of 55,567 operations: anaesthetic techniques and complications. Eye (Lond) 2009;23:50-5.
- Ezra DG, Allan BDS. Topical anaesthesia alone versus topical anaesthesia with intracameral lidocaine for phacoemulsification. Cochrane Database Syst Rev 2007, Issue 3. Art. No.: CD005276. DOI: 10.1002/14651858.CD005276.pub2.
- Navaleza JS, Pendse SJ, Blecher MH. Choosing anesthesia for cataract surgery. Ophthalmol Clin North Am 2006;19:233-7.
- Boezaart A, Berry R, Nell M. Topical anesthesia versus retrobulbar block for cataract surgery: the patients' perspective. J Clin Anesth 2000;12:58-60.
- Voon LW, Au Eong KG, Saw SM, et al. Effect of preoperative counseling on patient fear from the visual experience during phacoemulsification under topical anesthesia: Multicenter randomized clinical trial. J Cataract Refract Surg 2005;31:1966-9.
- Haripriya A, Tan CS, Venkatesh R, et al. Effect of preoperative counseling on fear from visual sensations during phacoemulsification under topical anesthesia. J Cataract Refract Surg 2011;37:814-8.
- Roberts T, Boytell K. A comparison of cataract surgery under topical anaesthesia with and without intracameral lignocaine. Clin Experiment Ophthalmol 2002;30:19-22.
- Rosenfeld SI, Litinsky SM, Snyder DA, et al. Effectiveness of monitored anesthesia care in cataract surgery. Ophthalmology 1999;106:1256-60; discussion 1261.
- 27Zakrzewski PA, Friel T, Fox G, Braga-Mele R. Monitored anesthesia care provided by registered respiratory care practitioners during cataract surgery: a report of 1957 cases. Ophthalmology 2005;112:272-7.
- Tantri A, Clark C, Huber P, et al. Anesthesia monitoring by registered nurses during cataract surgery: assessment of need for intraoperative anesthesia consultation. J Cataract Refract Surg 2006;32:1115-8.
- Bellan L, Gooi A, Rehsia S. The Misericordia Health Centre cataract comfort study. Can J Ophthalmol 2002;37:155-60.
- Erb T, Sluga M, Hampl KF, et al. Preoperative anxiolysis with minimal sedation in elderly patients: bromazepam or clorazepate-dipotassium? Acta Anaesthesiol Scand 1998;42:97-101.
- Boezaart AP, Berry RA, Laubscher JJ, Nell ML. Evaluation of anxiolysis and pain associated with combined peri- and retrobulbar eye block for cataract surgery. J Clin Anesth 1998;10:204-10.
- West ES, Behrens A, McDonnell PJ, et al. The incidence of endophthalmitis after cataract surgery among the U.S. Medicare population increased between 1994 and 2001. Ophthalmology 2005;112:1388-94.
- Taban M, Behrens A, Newcomb RL, et al. Acute endophthalmitis following cataract surgery: a systematic review of the literature. Arch Ophthalmol 2005;123:613-20.
- Taban M, Behrens A, Newcomb RL, et al. Incidence of acute endophthalmitis following penetrating keratoplasty: a systematic review. Arch Ophthalmol 2005;123:605-9.
- Cooper BA, Holekamp NM, Bohigian G, Thompson PA. Case-control study of endophthalmitis after cataract surgery comparing scleral tunnel and clear corneal wounds. Am J Ophthalmol 2003;136:300-5.
- Colleaux KM, Hamilton WK. Effect of prophylactic antibiotics and incision type on the incidence of endophthalmitis after cataract surgery. Can J Ophthalmol 2000;35:373-8.
- Nagaki Y, Hayasaka S, Kadoi C, et al. Bacterial endophthalmitis after small-incision cataract surgery. effect of incision placement and intraocular lens type. J Cataract Refract Surg 2003;29:20-6.
- McDonnell PJ, Taban M, Sarayba M, et al. Dynamic morphology of clear corneal cataract incisions. Ophthalmology 2003;110:2342-8.
- Taban M, Rao B, Reznik J, et al. Dynamic morphology of sutureless cataract wounds--effect of incision angle and location. Surv Ophthalmol 2004;49 Suppl 2:S62-72.
- 28Sarayba MA, Taban M, Ignacio TS, et al. Inflow of ocular surface fluid through clear corneal cataract incisions: a laboratory model. Am J Ophthalmol 2004;138:206-10.
- Nichamin LD, Chang DF, Johnson SH, et al. ASCRS White Paper: what is the association between clear corneal cataract incisions and postoperative endophthalmitis? J Cataract Refract Surg 2006;32:1556-9.
- Taban M, Sarayba MA, Ignacio TS, et al. Ingress of India ink into the anterior chamber through sutureless clear corneal cataract wounds. Arch Ophthalmol 2005;123:643-8.
- Eifrig CW, Flynn HW Jr, Scott IU, Newton J. Acute-onset postoperative endophthalmitis: review of incidence and visual outcomes (1995-2001). Ophthalmic Surg Lasers 2002;33:373-8.
- Miller JJ, Scott IU, Flynn HW Jr, et al. Acute-onset endophthalmitis after cataract surgery (2000-2004): incidence, clinical settings, and visual acuity outcomes after treatment. Am J Ophthalmol 2005;139:983-7.
- Oshika T, Hatano H, Kuwayama Y, et al. Incidence of endophthalmitis after cataract surgery in Japan. Acta Ophthalmol Scand 2007;85:848-51.
- Wong TY, Chee SP. The epidemiology of acute endophthalmitis after cataract surgery in an Asian population. Ophthalmology 2004;111:699-705.
- Koc F, Sen E, Demirbay P, et al. Factors influencing treatment results in pseudophakic endophthalmitis. Eur J Ophthalmol 2002;12:34-9.
- Schmitz S, Dick HB, Krummenauer F, Pfeiffer N. Endophthalmitis in cataract surgery: results of a German survey. Ophthalmology 1999;106:1869-77.
- Hatch WV, Cernat G, Wong D, et al. Risk factors for acute endophthalmitis after cataract surgery: a population-based study. Ophthalmology 2009;116:425-30.
- Haapala TT, Nelimarkka L, Saari JM, et al. Endophthalmitis following cataract surgery in southwest Finland from 1987 to 2000. Graefes Arch Clin Exp Ophthalmol 2005;243:1010-7.
- Ravindran RD, Venkatesh R, Chang DF, et al. Incidence of post-cataract endophthalmitis at Aravind Eye Hospital: outcomes of more than 42,000 consecutive cases using standardized sterilization and prophylaxis protocols. J Cataract Refract Surg 2009;35:629-36.
- Wejde G, Samolov B, Seregard S, et al. Risk factors for endophthalmitis following cataract surgery: a retrospective case-control study. J Hosp Infect 2005;61:251-6.
- Prophylaxis of postoperative endophthalmitis following cataract surgery: results of the ESCRS multicenter study and identification of risk factors. J Cataract Refract Surg 2007;33:978-88.
- Raskin EM, Speaker MG, McCormick SA, et al. Influence of haptic materials on the adherence of staphylococci to intraocular lenses. Arch Ophthalmol 1993;111:250-3.
- Patwardhan A, Rao GP, Saha K, Craig EA. Incidence and outcomes evaluation of endophthalmitis management after phacoemulsification and 3-piece silicone intraocular lens implantation over 6 years in a single eye unit. J Cataract Refract Surg 2006;32:1018-21.
- Kodjikian L, Renaud FN, Roques C, et al. In vitro influence of vancomycin on adhesion of a Staphylococcus epidermidis strain encoding intercellular adhesion locus ica to intraocular lenses. J Cataract Refract Surg 2005;31:1050-8.
- Ozkan B, Karabas VL, Gundes S, et al. Effect of vancomycin, teicoplanin, and cefuroxime on Staphylococcus epidermidis adherence to intraocular lenses. J Cataract Refract Surg 2005;31:1814-20.
- Mayer E, Cadman D, Ewings P, et al. A 10 year retrospective survey of cataract surgery and endophthalmitis in a single eye unit: injectable lenses lower the incidence of endophthalmitis. Br J Ophthalmol 2003;87:867-9.
- Leslie T, Aitken DA, Barrie T, Kirkness CM. Residual debris as a potential cause of postphacoemulsification endophthalmitis. Eye 2003;17:506-12.
- Zaluski S, Clayman HM, Karsenti G, et al. Pseudomonas aeruginosa endophthalmitis caused by contamination of the internal fluid pathways of a phacoemulsifier. J Cataract Refract Surg 1999;25:540-5.
- Outbreaks of postoperative bacterial endophthalmitis caused by intrinsically contaminated ophthalmic solutions--Thailand, 1992, and Canada, 1993. MMWR Morb Mortal Wkly Rep 1996;45:491-4.
- Mino de Kaspar H, Grasbon T, Kampik A. Automated surgical equipment requires routine disinfection of vacuum control manifold to prevent postoperative endophthalmitis. Ophthalmology 2000;107:685-90.
- Tarkkanen A, Raivio V, Anttila VJ, et al. Fungal endophthalmitis caused by Paecilomyces variotii following cataract surgery: a presumed operating room air-conditioning system contamination. Acta Ophthalmol Scand 2004;82:232-5.
- Fridkin SK, Kremer FB, Bland LA, et al. Acremonium kiliense endophthalmitis that occurred after cataract extraction in an ambulatory surgical center and was traced to an environmental reservoir. Clin Infect Dis 1996;22:222-7.
- Speaker MG, Milch FA, Shah MK, et al. Role of external bacterial flora in the pathogenesis of acute postoperative endophthalmitis. Ophthalmology 1991;98:639-49; discussion 650.
- Ciulla TA, Starr MB, Masket S. Bacterial endophthalmitis prophylaxis for cataract surgery: an evidence-based update. Ophthalmology 2002;109:13-24.
- Speaker MG, Menikoff JA. Prophylaxis of endophthalmitis with topical povidone-iodine. Ophthalmology 1991;98:1769-75.
- Carrim ZI, Mackie G, Gallacher G, Wykes WN. The efficacy of 5% povidone-iodine for 3 minutes prior to cataract surgery. Eur J Ophthalmol 2009;19:560-4.
- Ferguson AW, Scott JA, McGavigan J, et al. Comparison of 5% povidone-iodine solution against 1% povidone-iodine solution in preoperative cataract surgery antisepsis: a prospective randomised double blind study. Br J Ophthalmol 2003;87:163-7.
- Boden JH, Myers ML, Lee T, et al. Effect of lidocaine gel on povidone-iodine antisepsis and microbial survival. J Cataract Refract Surg 2008;34:1773-5.
- Hariprasad SM, Shah GK, Mieler WF, et al. Vitreous and aqueous penetration of orally administered moxifloxacin in humans. Arch Ophthalmol 2006;124:178-82.
- Kampougeris G, Antoniadou A, Kavouklis E, et al. Penetration of moxifloxacin into the human aqueous humour after oral administration. Br J Ophthalmol 2005;89:628-31.
- Garcia-Saenz MC, Arias-Puente A, Fresnadillo-Martinez MJ, Carrasco-Font C. Human aqueous humor levels of oral ciprofloxacin, levofloxacin, and moxifloxacin. J Cataract Refract Surg 2001;27:1969-74.
- Ng JQ, Morlet N, Pearman JW, et al. Management and outcomes of postoperative endophthalmitis since the Endophthalmitis Vitrectomy Study: the Endophthalmitis Population Study of Western Australia (EPSWA)'s fifth report. Ophthalmology 2005;112:1199-206.
- Montan PG, Wejde G, Koranyi G, Rylander M. Prophylactic intracameral cefuroxime. Efficacy in preventing endophthalmitis after cataract surgery. J Cataract Refract Surg 2002;28:977-81.
- Garat M, Moser CL, Alonso-Tarres C, et al. Intracameral cefazolin to prevent endophthalmitis in cataract surgery: 3-year retrospective study. J Cataract Refract Surg 2005;31:2230-4.
- Ndegwa S, Cimon K, Severn M. Rapid Response Report: Peer-Reviewed Summary with Critical Appraisal. Intracameral antibiotics for the prevention of endophthalmitis post-cataract surgery: review of clinical and cost-effectiveness and guidelines. Ottawa, Canada: Canadian Agency for Drugs and Technologies in Health; October 2010. Available at: www.cadth.ca/media/pdf/M0019_Intracameral_Antiobiotics_L3_e.pdf. Accessed May 4, 2011.
- Romero P, Mendez I, Salvat M, et al. Intracameral cefazolin as prophylaxis against endophthalmitis in cataract surgery. J Cataract Refract Surg 2006;32:438-41.
- Yu-Wai-Man P, Morgan SJ, Hildreth AJ, et al. Efficacy of intracameral and subconjunctival cefuroxime in preventing endophthalmitis after cataract surgery. J Cataract Refract Surg 2008;34:447-51.
- Arbisser LB. Safety of intracameral moxifloxacin for prophylaxis of endophthalmitis after cataract surgery. J Cataract Refract Surg 2008;34:1114-20.
- Espiritu CR, Caparas VL, Bolinao JG. Safety of prophylactic intracameral moxifloxacin 0.5% ophthalmic solution in cataract surgery patients. J Cataract Refract Surg 2007;33:63-8.
- Lane SS, Osher RH, Masket S, Belani S. Evaluation of the safety of prophylactic intracameral moxifloxacin in cataract surgery. J Cataract Refract Surg 2008;34:1451-9.
- Delyfer MN, Rougier MB, Leoni S, et al. Ocular toxicity after intracameral injection of very high doses of cefuroxime during cataract surgery. J Cataract Refract Surg 2011;37:271-8.
- Chang DF, Braga-Mele R, Mamalis N, et al, ASCRS Cataract Clinical Committee. Prophylaxis of postoperative endophthalmitis after cataract surgery: results of the 2007 ASCRS member survey. J Cataract Refract Surg 2007;33:1801-5.
- Brown GC, Eagle RC, Shakin EP, et al. Retinal toxicity of intravitreal gentamicin. Arch Ophthalmol 1990;108:1740-4.
- Rosha DS, Ng JQ, Morlet N, et al. Cataract surgery practice and endophthalmitis prevention by Australian and New Zealand ophthalmologists. Clin Experiment Ophthalmol 2006;34:535-44.
- Sharifi E, Porco TC, Naseri A. Cost-effectiveness analysis of intracameral cefuroxime use for prophylaxis of endophthalmitis after cataract surgery. Ophthalmology 2009;116:1887-96.
- Wu PC, Li M, Chang SJ, et al. Risk of endophthalmitis after cataract surgery using different protocols for povidone- iodine preoperative disinfection. J Ocul Pharmacol Ther 2006;22:54-61.
- Mamalis N, Edelhauser HF, Dawson DG, et al. Toxic anterior segment syndrome. J Cataract Refract Surg 2006;32:324-33.
- Mamalis N. Toxic anterior segment syndrome. Focal Points: Clinical Modules for Ophthalmologists. Module 10. San Francisco, CA: American Academy of Ophthalmology; 2009.
- Analeyz, Inc. 2010 survey practice styles and preferences of U.S. ASCRS members. Available at: www.analeyz.com/. Accessed June 24, 2011.
- Minassian DC, Rosen P, Dart JK, et al. Extracapsular cataract extraction compared with small incision surgery by phacoemulsification: a randomised trial. Br J Ophthalmol 2001;85:822-9.
- Nagy Z, Takacs A, Filkorn T, Sarayba M. Initial clinical evaluation of an intraocular femtosecond laser in cataract surgery. J Refract Surg 2009;25:1053-60.
- Masket S, Sarayba M, Ignacio T, Fram N. Femtosecond laser-assisted cataract incisions: architectural stability and reproducibility. J Cataract Refract Surg 2010;36:1048-9.
- Fine IH, Hoffman RS, Packer M. Profile of clear corneal cataract incisions demonstrated by ocular coherence tomography. J Cataract Refract Surg 2007;33:94-7.
- Alio J, Rodriguez-Prats JL, Galal A, Ramzy M. Outcomes of microincision cataract surgery versus coaxial phacoemulsification. Ophthalmology 2005;112:1997-2003.
- Elkady B, Pinero D, Alio JL. Corneal incision quality: microincision cataract surgery versus microcoaxial phacoemulsification. J Cataract Refract Surg 2009;35:466-74.
- Calladine D, Packard R. Clear corneal incision architecture in the immediate postoperative period evaluated using optical coherence tomography. J Cataract Refract Surg 2007;33:1429-35.
- Mardelli PG, Mehanna CJ. Phacoanaphylactic endophthalmitis secondary to capsular block syndrome. J Cataract Refract Surg 2007;33:921-2.
- Wilczynski M, Supady E, Loba P, et al. Comparison of early corneal endothelial cell loss after coaxial phacoemulsification through 1.8 mm microincision and bimanual phacoemulsification through 1.7 mm microincision. J Cataract Refract Surg 2009;35:1570-4.
- Hu V, Hughes EH, Patel N, Whitefield LA. The effect of aqualase and phacoemulsification on the corneal endothelium. Cornea 2010;29:247-50.
- Liyanage SE, Angunawela RI, Wong SC, Little BC. Anterior chamber instability caused by incisional leakage in coaxial phacoemulsification. J Cataract Refract Surg 2009;35:1003-5.
- Bissen-Miyajima H. Ophthalmic viscosurgical devices. Curr Opin Ophthalmol 2008;19:50-4.
- Gimbel HV, Neuhann T. Development, advantages, and methods of the continuous circular capsulorhexis technique. J Cataract Refract Surg 1990;16:31-7.
- Nixon DR. In vivo digital imaging of the square-edged barrier effect of a silicone intraocular lens. J Cataract Refract Surg 2004;30:2574-84.
- Koch DD, Liu JF. Multilamellar hydrodissection in phacoemulsification and planned extracapsular surgery. J Cataract Refract Surg 1990;16:559-62.
- Peng Q, Apple DJ, Visessook N, et al. Surgical prevention of posterior capsule opacification. Part 2: Enhancement of cortical cleanup by focusing on hydrodissection. J Cataract Refract Surg 2000;26:188-97.
- Vasavada AR, Dholakia SA, Raj SM, Singh R. Effect of cortical cleaving hydrodissection on posterior capsule opacification in age-related nuclear cataract. J Cataract Refract Surg 2006;32:1196-200.
- Gimbel HV. Divide and conquer nucleofractis phacoemulsification: development and variations. J Cataract Refract Surg 1991;17:281-91.
- Koch PS, Katzen LE. Stop and chop phacoemulsification. J Cataract Refract Surg 1994;20:566-70.
- Packer M, Fine IH, Hoffman RS, Smith JH. Techniques of phacoemulsification. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology on DVD-ROM. 2009 edition. Philadelphia, PA: Lippincott Williams & Wilkins, 2009.
- Hoffman RS, Fine IH, Packer M. Scleral fixation without conjunctival dissection. J Cataract Refract Surg 2006;32:1907-12.
- Rainer G, Stifter E, Luksch A, Menapace R. Comparison of the effect of Viscoat and DuoVisc on postoperative intraocular pressure after small-incision cataract surgery. J Cataract Refract Surg 2008;34:253-7.
- Vasavada AR, Praveen MR, Pandita D, et al. Effect of stromal hydration of clear corneal incisions: quantifying ingress of trypan blue into the anterior chamber after phacoemulsification. J Cataract Refract Surg 2007;33:623-7.
- Chee SP. Clear corneal incision leakage after phacoemulsification--detection using povidone iodine 5%. Int Ophthalmol 2005;26:175-9.
- Nielsen PJ. Prospective evaluation of surgically induced astigmatism and astigmatic keratotomy effects of various self-sealing small incisions. J Cataract Refract Surg 1995;21:43-8.
- Kaufmann C, Peter J, Ooi K, et al. Queen Elizabeth Astigmatism Study Group. Limbal relaxing incisions versus on-axis incisions to reduce corneal astigmatism at the time of cataract surgery. J Cataract Refract Surg 2005;31:2261-5.
- Borasio E, Mehta JS, Maurino V. Surgically induced astigmatism after phacoemulsification in eyes with mild to moderate corneal astigmatism: temporal versus on-axis clear corneal incisions. J Cataract Refract Surg 2006;32:565-72.
- Olson RJ, Crandall AS. Prospective randomized comparison of phacoemulsification cataract surgery with a 3.2-mm vs a 5.5-mm sutureless incision. Am J Ophthalmol 1998;125:612-20.
- Laurell CG, Zetterstrom C, Philipson B, Syren-Nordqvist S. Randomized study of the blood-aqueous barrier reaction after phacoemulsification and extracapsular cataract extraction. Acta Ophthalmol Scand 1998;76:573-8.
- Pande MV, Spalton DJ, Kerr-Muir MG, Marshall J. Postoperative inflammatory response to phacoemulsification and extracapsular cataract surgery: aqueous flare and cells. J Cataract Refract Surg 1996;22 Suppl 1:770-4.
- Steinert RF, Brint SF, White SM, Fine IH. Astigmatism after small incision cataract surgery. A prospective, randomized, multicenter comparison of 4- and 6.5-mm incisions. Ophthalmology 1991;98:417-23; discussion 423-4.
- Hayashi K, Hayashi H, Nakao F, Hayashi F. The correlation between incision size and corneal shape changes in sutureless cataract surgery. Ophthalmology 1995;102:550-6.
- Kohnen T, Dick B, Jacobi KW. Comparison of the induced astigmatism after temporal clear corneal tunnel incisions of different sizes. J Cataract Refract Surg 1995;21:417-24.
- Oshika T, Nagahara K, Yaguchi S, et al. Three year prospective, randomized evaluation of intraocular lens implantation through 3.2 and 5.5 mm incisions. J Cataract Refract Surg 1998;24:509-14.
- Wang J, Zhang EK, Fan WY, et al. The effect of micro-incision and small-incision coaxial phaco-emulsification on corneal astigmatism. Clin Experiment Ophthalmol 2009;37:664-9.
- Masket S, Wang L, Belani S. Induced astigmatism with 2.2- and 3.0-mm coaxial phacoemulsification incisions. J Refract Surg 2009;25:21-4.
- Packer M, Fine IH, Hoffman RS. Refractive lens surgery. Ophthalmol Clin North Am 2006;19:77-88, vi.
- Denoyer A, Denoyer L, Marotte D, et al. Intraindividual comparative study of corneal and ocular wavefront aberrations after biaxial microincision versus coaxial small-incision cataract surgery. Br J Ophthalmol 2008;92:1679-84.
- Baranano AE, Wu J, Mazhar K, et al, Los Angeles Latino Eye Study Group. Visual acuity outcomes after cataract extraction in adult latinos. The Los Angeles Latino Eye Study. Ophthalmology 2008;115:815-21.
- Dick HB, Augustin AJ. Lens implant selection with absence of capsular support. Curr Opin Ophthalmol 2001;12:47-57.
- Werner L, Tetz M, Feldmann I, Bucker M. Evaluating and defining the sharpness of intraocular lenses: microedge structure of commercially available square-edged hydrophilic intraocular lenses. J Cataract Refract Surg 2009;35:556-66.
- Bournas P, Drazinos S, Kanellas D, et al. Dysphotopsia after cataract surgery: comparison of four different intraocular lenses. Ophthalmologica 2007;221:378-83.
- Buehl W, Findl O. Effect of intraocular lens design on posterior capsule opacification. J Cataract Refract Surg 2008;34:1976-85.
- Vock L, Crnej A, Findl O, et al. Posterior capsule opacification in silicone and hydrophobic acrylic intraocular lenses with sharp-edge optics six years after surgery. Am J Ophthalmol 2009;147:683-90.
- Kohnen S, Ferrer A, Brauweiler P. Visual function in pseudophakic eyes with poly(methyl methacrylate), silicone, and acrylic intraocular lenses. J Cataract Refract Surg 1996;22 Suppl 2:1303-7.
- Brown DC, Grabow HB, Martin RG, et al. Staar Collamer intraocular lens: clinical results from the phase I FDA core study. J Cataract Refract Surg 1998;24:1032-8.
- Cheng JW, Wei RL, Cai JP, et al. Efficacy of different intraocular lens materials and optic edge designs in preventing posterior capsular opacification: a meta-analysis. Am J Ophthalmol 2007;143:428-36.
- Werner L. Glistenings and surface light scattering in intraocular lenses. J Cataract Refract Surg 2010;36:1398-420.
- Richter-Mueksch S, Kahraman G, Amon M, et al. Uveal and capsular biocompatibility after implantation of sharp-edged hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses in eyes with pseudoexfoliation syndrome. J Cataract Refract Surg 2007;33:1414-8.
- Schild G, Amon M, Abela-Formanek C, et al. Uveal and capsular biocompatibility of a single-piece, sharp-edged hydrophilic acrylic intraocular lens with collagen (Collamer): 1-year results. J Cataract Refract Surg 2004;30:1254-8.
- Abela-Formanek C, Amon M, Schild G, et al. Uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses. J Cataract Refract Surg 2002;28:50-61.
- Mamalis N. Incision width after phacoemulsification with foldable intraocular lens implantation. J Cataract Refract Surg 2000;26:237-41.
- Shimizu K, Kobayashi K, Takayama S, Zhaobin G. Preloaded injector for intraocular lens implantation without the use of ophthalmic viscosurgical devices. J Cataract Refract Surg 2008;34:1157-60.
- Wagoner MD, Cox TA, Ariyasu RG, et al. Intraocular lens implantation in the absence of capsular support: a report by the American Academy of Ophthalmology. Ophthalmology 2003;110:840-59.
- Donaldson KE, Gorscak JJ, Budenz DL, et al. Anterior chamber and sutured posterior chamber intraocular lenses in eyes with poor capsular support. J Cataract Refract Surg 2005;31:903-9.
- Kwong YY, Yuen HK, Lam RF, et al. Comparison of outcomes of primary scleral-fixated versus primary anterior chamber intraocular lens implantation in complicated cataract surgeries. Ophthalmology 2007;114:80-5.
- Condon GP, Masket S, Kranemann C, et al. Small-incision iris fixation of foldable intraocular lenses in the absence of capsule support. Ophthalmology 2007;114:1311-8.
- Assia EI, Nemet A, Sachs D. Bilateral spontaneous subluxation of scleral-fixated intraocular lenses. J Cataract Refract Surg 2002;28:2214-6.
- Price MO, Price FW Jr, Werner L, et al. Late dislocation of scleral-sutured posterior chamber intraocular lenses. J Cataract Refract Surg 2005;31:1320-6.
- Sasahara M, Kiryu J, Yoshimura N. Endoscope-assisted transscleral suture fixation to reduce the incidence of intraocular lens dislocation. J Cataract Refract Surg 2005;31:1777-80.
- Kamal AM, Hanafy M, Ehsan A, Tomerak RH. Ultrasound biomicroscopy comparison of ab interno and ab externo scleral fixation of posterior chamber intraocular lenses. J Cataract Refract Surg 2009;35:881-4.
- Mura JJ, Pavlin CJ, Condon GP, et al. Ultrasound biomicroscopic analysis of iris-sutured foldable posterior chamber intraocular lenses. Am J Ophthalmol 2010;149:245-52.
- Bellucci R, Scialdone A, Buratto L, et al. Visual acuity and contrast sensitivity comparison between Tecnis and AcrySof SA60AT intraocular lenses: A multicenter randomized study. J Cataract Refract Surg 2005;31:712-7.
- Packer M, Fine IH, Hoffman RS, Piers PA. Improved functional vision with a modified prolate intraocular lens. J Cataract Refract Surg 2004;30:986-92.
- Holladay JT, Piers PA, Koranyi G, et al. A new intraocular lens design to reduce spherical aberration of pseudophakic eyes. J Refract Surg 2002;18:683-91.
- Kurz S, Krummenauer F, Thieme H, Dick HB. Contrast sensitivity after implantation of a spherical versus an aspherical intraocular lens in biaxial microincision cataract surgery. J Cataract Refract Surg 2007;33:393-400.
- Packer M, Fine IH, Hoffman RS, Piers PA. Prospective randomized trial of an anterior surface modified prolate intraocular lens. J Refract Surg 2002;18:692-6.
- Kohnen T, Klaproth OK, Buhren J. Effect of intraocular lens asphericity on quality of vision after cataract removal: an intraindividual comparison. Ophthalmology 2009;116:1697-706.
- Chen WR, Ye HH, Qian YY, et al. Comparison of higher-order aberrations and contrast sensitivity between Tecnis Z9001 and CeeOn 911A intraocular lenses: a prospective randomized study. Chin Med J (Engl) 2006;119:1779-84.
- Ohtani S, Gekka S, Honbou M, et al. One-year prospective intrapatient comparison of aspherical and spherical intraocular lenses in patients with bilateral cataract. Am J Ophthalmol 2009;147:984-9.
- Kasper T, Buhren J, Kohnen T. Intraindividual comparison of higher-order aberrations after implantation of aspherical and spherical intraocular lenses as a function of pupil diameter. J Cataract Refract Surg 2006;32:78-84.
- Tzelikis PF, Akaishi L, Trindade FC, Boteon JE. Spherical aberration and contrast sensitivity in eyes implanted with aspheric and spherical intraocular lenses: a comparative study. Am J Ophthalmol 2008;145:827-33.
- Tzelikis PF, Akaishi L, Trindade FC, Boteon JE. Ocular aberrations and contrast sensitivity after cataract surgery with AcrySof IQ intraocular lens implantation Clinical comparative study. J Cataract Refract Surg 2007;33:1918-24.
- Santhiago MR, Netto MV, Barreto J, Jr., et al. Wavefront analysis, contrast sensitivity, and depth of focus after cataract surgery with aspherical intraocular lens implantation. Am J Ophthalmol 2010;149:383-9.
- Nochez Y, Favard A, Majzoub S, Pisella PJ. Measurement of corneal aberrations for customisation of intraocular lens asphericity: impact on quality of vision after micro-incision cataract surgery. Br J Ophthalmol 2010;94:440-4.
- van Gaalen KW, Koopmans SA, Jansonius NM, Kooijman AC. Clinical comparison of the optical performance of aspheric and spherical intraocular lenses. J Cataract Refract Surg 2010;36:34-43.
- Su PY, Hu FR. Intraindividual comparison of functional vision and higher order aberrations after implantation of aspheric and spherical intraocular lenses. J Refract Surg 2009;25:265-72.
- Munoz G, Albarran-Diego C, Montes-Mico R, et al. Spherical aberration and contrast sensitivity after cataract surgery with the Tecnis Z9000 intraocular lens. J Cataract Refract Surg 2006;32:1320-7.
- Nanavaty MA, Spalton DJ, Boyce J, et al. Wavefront aberrations, depth of focus, and contrast sensitivity with aspheric and spherical intraocular lenses: fellow-eye study. J Cataract Refract Surg 2009;35:663-71.
- Yamaguchi T, Negishi K, Ono T, et al. Feasibility of spherical aberration correction with aspheric intraocular lenses in cataract surgery based on individual pupil diameter. J Cataract Refract Surg 2009;35:1725-33.
- Baumeister M, Buhren J, Kohnen T. Tilt and decentration of spherical and aspheric intraocular lenses: effect on higher-order aberrations. J Cataract Refract Surg 2009;35:1006-12.
- Packer M, Fine IH, Hoffman RS. Aspheric intraocular lens selection based on corneal wavefront. J Refract Surg 2009;25:12-20.
- Montes-Mico R, Ferrer-Blasco T, Cervino A. Analysis of the possible benefits of aspheric intraocular lenses: review of the literature. J Cataract Refract Surg 2009;35:172-81.
- Hoffer KJ. Biometry of 7,500 cataractous eyes. Am J Ophthalmol 1980;90:360-8, correction 890.
- Grabow HB. Intraocular correction of refractive errors. In: Kershner RM, ed. Refractive Keratotomy for Cataract Surgery and the Correction of Astigmatism. Thorofare, NJ: SLACK, 1994.
- Lane SS, Ernest P, Miller KM, et al. Comparison of clinical and patient-reported outcomes with bilateral AcrySof toric or spherical control intraocular lenses. J Refract Surg 2009;25:899-901.
- Ruiz-Mesa R, Carrasco-Sanchez D, Diaz-Alvarez SB, et al. Refractive lens exchange with foldable toric intraocular lens. Am J Ophthalmol 2009;147:990-6.
- Gills JP, Gayton JL. Reducing pre-existing astigmatism. In: Gills JP, Fenzl R, Martin RG, eds. Cataract Surgery : The State of the Art. Thorofare, NJ: SLACK, 1998.
- Till JS, Yoder PR, Jr, Wilcox TK, Spielman JL. Toric intraocular lens implantation: 100 consecutive cases. J Cataract Refract Surg 2002;28:295-301.
- Chang DF. Comparative rotational stability of single-piece open-loop acrylic and plate-haptic silicone toric intraocular lenses. J Cataract Refract Surg 2008;34:1842-7.
- McDonnell PJ, Lee P, Spritzer K, et al. Associations of presbyopia with vision-targeted health-related quality of life. Arch Ophthalmol 2003;121:1577-81.
- Dick HB, Krummenauer F, Schwenn O, et al. Objective and subjective evaluation of photic phenomena after monofocal and multifocal intraocular lens implantation. Ophthalmology 1999;106:1878-86.
- Vaquero-Ruano M, Encinas JL, Millan I, et al. AMO array multifocal versus monofocal intraocular lenses: long-term follow-up. J Cataract Refract Surg 1998;24:118-23.
- Greenbaum S. Monovision pseudophakia. J Cataract Refract Surg 2002;28:1439-43.
- Zhang F, Sugar A, Jacobsen G, Collins M. Visual function and spectacle independence after cataract surgery: bilateral diffractive multifocal intraocular lenses versus monovision pseudophakia. J Cataract Refract Surg 2011;37:853-8.
- Finkelman YM, Ng JQ, Barrett GD. Patient satisfaction and visual function after pseudophakic monovision. J Cataract Refract Surg 2009;35:998-1002.
- Ito M, Shimizu K, Amano R, Handa T. Assessment of visual performance in pseudophakic monovision. J Cataract Refract Surg 2009;35:710-4.
- Leyland M, Zinicola E. Multifocal versus monofocal intraocular lenses in cataract surgery: a systematic review. Ophthalmology 2003;110:1789-98.
- Woodward MA, Randleman JB, Stulting RD. Dissatisfaction after multifocal intraocular lens implantation. J Cataract Refract Surg 2009;35:992-7.
- Packer M, Chu YR, Waltz KL, et al. Evaluation of the aspheric Tecnis multifocal intraocular lens: one-year results from the first cohort of the food and drug administration clinical trial. Am J Ophthalmol 2010;149:577-84.
- Cumming JS, Colvard DM, Dell SJ, et al. Clinical evaluation of the Crystalens AT-45 accommodating intraocular lens Results of the U.S. Food and Drug Administration clinical trial. J Cataract Refract Surg 2006;32:812-25.
- Pepose JS, Qazi MA, Davies J, et al. Visual performance of patients with bilateral vs combination Crystalens, ReZoom, and ReSTOR intraocular lens implants. Am J Ophthalmol 2007;144:347-57.
- Lundstrom M, Barry P, Leite E, et al. 1998 European Cataract Outcome Study: report from the European Cataract Outcome Study Group. J Cataract Refract Surg 2001;27:1176-84.
- Lum F, Schein O, Schachat AP, et al. Initial two years of experience with the AAO National Eyecare Outcomes Network (NEON) cataract surgery database. Ophthalmology 2000;107:691-7.
- Jaycock P, Johnston RL, Taylor H, et al. The Cataract National Dataset electronic multi-centre audit of 55,567 operations: updating benchmark standards of care in the United Kingdom and internationally. Eye (Lond) 2009;23:38-49.
- Albanis CV, Dwyer MA, Ernest JT. Outcomes of extracapsular cataract extraction and phacoemulsification performed in a university training program. Ophthalmic Surg Lasers 1998;29:643-8.
- Blomquist PH, Rugwani RM. Visual outcomes after vitreous loss during cataract surgery performed by residents. J Cataract Refract Surg 2002;28:847-52.
- Corey RP, Olson RJ. Surgical outcomes of cataract extractions performed by residents using phacoemulsification. J Cataract Refract Surg 1998;24:66-72.
- Karp KO, Albanis CV, Pearlman JB, Goins KM. Outcomes of temporal clear cornea versus superior scleral tunnel phacoemulsification incisions in a university training program. Ophthalmic Surg Lasers 2001;32:228-32.
- Randleman JB, Srivastava SK, Aaron MM. Phacoemulsification with topical anesthesia performed by resident surgeons. J Cataract Refract Surg 2004;30:149-54.
- Tarbet KJ, Mamalis N, Theurer J, et al. Complications and results of phacoemulsification performed by residents. J Cataract Refract Surg 1995;21:661-5.
- Quillen DA, Phipps SJ. Visual outcomes and incidence of vitreous loss for residents performing phacoemulsification without prior planned extracapsular cataract extraction experience. Am J Ophthalmol 2003;135:732-3.
- Mangione CM, Orav EJ, Lawrence MG, et al. Prediction of visual function after cataract surgery. A prospectively validated model. Arch Ophthalmol 1995;113:1305-11.
- Amesbury EC, Grossberg AL, Hong DM, Miller KM. Functional visual outcomes of cataract surgery in patients with 20/20 or better preoperative visual acuity. J Cataract Refract Surg 2009;35:1505-8.
- Mozaffarieh M, Heinzl H, Sacu S, Wedrich A. Clinical outcomes of phacoemulsification cataract surgery in diabetes patients: visual function (VF-14), visual acuity and patient satisfaction. Acta Ophthalmol Scand 2005;83:176-83.
- Pham TQ, Cugati S, Rochtchina E, et al. Age-related maculopathy and cataract surgery outcomes: visual acuity and health-related quality of life. Eye 2007;21:324-30.
- Forooghian F, Agron E, Clemons TE, et al. Visual acuity outcomes after cataract surgery in patients with age-related macular degeneration: Age-Related Eye Disease Study report no. 27. Ophthalmology 2009;116:2093-100.
- Powe NR, Schein OD, Gieser SC, et al, Cataract Patient Outcome Research Team. Synthesis of the literature on visual acuity and complications following cataract extraction with intraocular lens implantation. Arch Ophthalmol 1994;112:239-52.
- Greenberg PB, Tseng VL, Wu WC, et al. Prevalence and predictors of ocular complications associated with cataract surgery in United States veterans. Ophthalmology 2011;118:507-14.
- Stein JD, Grossman DS, Mundy KM, et al. Severe adverse events after cataract surgery among medicare beneficiaries. Ophthalmology 2011;118:1716-23.
- Zaidi FH, Corbett MC, Burton BJ, Bloom PA. Raising the benchmark for the 21st century--the 1000 cataract operations audit and survey: outcomes, consultant-supervised training and sourcing NHS choice. Br J Ophthalmol 2007;91:731-6.
- Clark A, Morlet N, Ng JQ, et al. Whole population trends in complications of cataract surgery over 22 years in Western Australia. Ophthalmology 2011;118:1055-61.
- Chen CK, Tseng VL, Wu WC, Greenberg PB. A survey of the current role of manual extracapsular cataract extraction. J Cataract Refract Surg 2010;36:692-3.
- Ernest P, Rhem M, McDermott M, et al. Phacoemulsification conditions resulting in thermal wound injury. J Cataract Refract Surg 2001;27:1829-39.
- Sorensen T, Chan CC, Bradley M, et al. An ultrasound induced incision contracture survey of the United States and Canada. J Cataract Refract Surg. In press 2012.
- Cho YK, Kim MS. Perioperative modulating factors on astigmatism in sutured cataract surgery. Korean J Ophthalmol 2009;23:240-8.
- Marcon AS, Rapuano CJ, Jones MR, et al. Descemet's membrane detachment after cataract surgery: management and outcome. Ophthalmology 2002;109:2325-30.
- Hui JI, Fishler J, Karp CL, et al. Retained nuclear fragments in the anterior chamber after phacoemulsification with an intact posterior capsule. Ophthalmology 2006;113:1949-53.
- Van Gelder RN, Leveque TK. Cataract surgery in the setting of uveitis. Curr Opin Ophthalmol 2009;20:42-5.
- Clark WL, Kaiser PK, Flynn HW Jr, et al. Treatment strategies and visual acuity outcomes in chronic postoperative Propionibacterium acnes endophthalmitis. Ophthalmology 1999;106:1665-70.
- Cao X, Liu A, Zhang J, et al. Clinical analysis of endophthalmitis after phacoemulsification. Can J Ophthalmol 2007;42:844-8.
- Carrim ZI, Richardson J, Wykes WN. Incidence and visual outcome of acute endophthalmitis after cataract surgery--the experience of an eye department in Scotland. Br J Ophthalmol 2009;93:721-5.
- Fang YT, Chien LN, Ng YY, et al. Association of hospital and surgeon operation volume with the incidence of postoperative endophthalmitis: Taiwan experience. Eye (Lond) 2006;20:900-7.
- Lalitha P, Rajagopalan J, Prakash K, et al. Postcataract endophthalmitis in South India incidence and outcome. Ophthalmology 2005;112:1884-9.
- Garcia-Arumi J, Fonollosa A, Sararols L, et al. Topical anesthesia: possible risk factor for endophthalmitis after cataract extraction. J Cataract Refract Surg 2007;33:989-92.
- Lundstrom M. Endophthalmitis and incision construction. Curr Opin Ophthalmol 2006;17:68-71.
- Monica ML, Long DA. Nine-year safety with self-sealing corneal tunnel incision in clear cornea cataract surgery. Ophthalmology 2005;112:985-6.
- Lemley CA, Han DP. Endophthalmitis: a review of current evaluation and management. Retina 2007;27:662-80.
- Kernt M, Kampik A. Endophthalmitis: pathogenesis, clinical presentation, management, and perspectives. Clin Ophthalmol 2010;4:121-35.
- Montan PG, Koranyi G, Setterquist HE, et al. Endophthalmitis after cataract surgery: risk factors relating to technique and events of the operation and patient history: a retrospective case-control study. Ophthalmology 1998;105:2171-7.
- Somani S, Grinbaum A, Slomovic AR. Postoperative endophthalmitis: incidence, predisposing surgery, clinical course and outcome. Can J Ophthalmol 1997;32:303-10.
- Lalwani GA, Flynn HW Jr., Scott IU, et al. Acute-onset endophthalmitis after clear corneal cataract surgery (1996-2005). Clinical features, causative organisms, and visual acuity outcomes. Ophthalmology 2008;115:473-6.
- Ang GS, Whyte IF. Effect and outcomes of posterior capsule rupture in a district general hospital setting. J Cataract Refract Surg 2006;32:623-7.
- Chan FM, Mathur R, Ku JJ, et al. Rates of posterior capsule rupture during cataract surgery among different races in Singapore. Ann Acad Med Singapore 2006;35:698-700.
- Szijarto Z, Haszonits B, Biro Z, Kovacs B. Phacoemulsification on previously vitrectomized eyes: results of a 10-year-period. Eur J Ophthalmol 2007;17:601-4.
- Narendran N, Jaycock P, Johnston RL, et al. The Cataract National Dataset electronic multicentre audit of 55,567 operations: risk stratification for posterior capsule rupture and vitreous loss. Eye (Lond) 2009;23:31-7.
- Artzen D, Lundstrom M, Behndig A, et al. Capsule complication during cataract surgery: Case-control study of preoperative and intraoperative risk factors: Swedish Capsule Rupture Study Group report 2. J Cataract Refract Surg 2009;35:1688-93.
- Burk SE, Da Mata AP, Snyder ME, et al. Visualizing vitreous using Kenalog suspension. J Cataract Refract Surg 2003;29:645-51.
- von Lany H, Mahmood S, James CR, et al. Displacement of nuclear fragments into the vitreous complicating phacoemulsification surgery in the UK: clinical features, outcomes and management. Br J Ophthalmol 2008;92:493-5.
- Ho LY, Doft BH, Wang L, Bunker CH. Clinical predictors and outcomes of pars plana vitrectomy for retained lens material after cataract extraction. Am J Ophthalmol 2009;147:587-94.
- Schaal S, Barr CC. Management of retained lens fragments after cataract surgery with and without pars plana vitrectomy. J Cataract Refract Surg 2009;35:863-7.
- Chen CL, Wang TY, Cheng JH, et al. Immediate pars plana vitrectomy improves outcome in retained intravitreal lens fragments after phacoemulsification. Ophthalmologica 2008;222:277-83.
- Treumer F, Bunse A, Rudolf M, Roider J. Pars plana vitrectomy, phacoemulsification and intraocular lens implantation. Comparison of clinical complications in a combined versus two-step surgical approach. Graefes Arch Clin Exp Ophthalmol 2006;244:808-15.
- Alio JL, Ruiz-Moreno JM, Shabayek MH, et al. The risk of retinal detachment in high myopia after small incision coaxial phacoemulsification. Am J Ophthalmol 2007;144:93-8.
- Bhagwandien AC, Cheng YY, Wolfs RC, et al. Relationship between retinal detachment and biometry in 4262 cataractous eyes. Ophthalmology 2006;113:643-9.
- Boberg-Ans G, Henning V, Villumsen J, la Cour M. Longterm incidence of rhegmatogenous retinal detachment and survival in a defined population undergoing standardized phacoemulsification surgery. Acta Ophthalmol Scand 2006;84:613-8.
- Jakobsson G, Montan P, Zetterberg M, et al. Capsule complication during cataract surgery: Retinal detachment after cataract surgery with capsule complication: Swedish Capsule Rupture Study Group report 4. J Cataract Refract Surg 2009;35:1699-705.
- Neuhann IM, Neuhann TF, Heimann H, et al. Retinal detachment after phacoemulsification in high myopia: analysis of 2356 cases. J Cataract Refract Surg 2008;34:1644-57.
- Russell M, Gaskin B, Russell D, Polkinghorne PJ. Pseudophakic retinal detachment after phacoemulsification cataract surgery: Ten-year retrospective review. J Cataract Refract Surg 2006;32:442-5.
- Erie JC, Raecker MA, Baratz KH, et al. Risk of retinal detachment after cataract extraction, 1980-2004: a population-based study. Ophthalmology 2006;113:2026-32.
- Olsen G, Olson RJ. Update on a long-term, prospective study of capsulotomy and retinal detachment rates after cataract surgery. J Cataract Refract Surg 2000;26:1017-21.
- Speaker MG, Guerriero PN, Met JA, et al. A case-control study of risk factors for intraoperative suprachoroidal expulsive hemorrhage. Ophthalmology 1991;98:202-9; discussion 210.
- Obuchowska I, Mariak Z. Risk factors of massive suprachoroidal hemorrhage during extracapsular cataract extraction surgery. Eur J Ophthalmol 2005;15:712-7.
- Benzimra JD, Johnston RL, Jaycock P, et al. The Cataract National Dataset electronic multicentre audit of 55,567 operations: antiplatelet and anticoagulant medications. Eye (Lond) 2009;23:10-6.
- Ling R, Cole M, James C, et al. Suprachoroidal haemorrhage complicating cataract surgery in the UK: epidemiology, clinical features, management, and outcomes. Br J Ophthalmol 2004;88:478-80.
- Singal N, Hopkins J. Pseudophakic cystoid macular edema: ketorolac alone vs. ketorolac plus prednisolone. Can J Ophthalmol 2004;39:245-50.
- Wittpenn JR, Silverstein S, Heier J, et al. A randomized, masked comparison of topical ketorolac 0.4% plus steroid vs steroid alone in low-risk cataract surgery patients. Am J Ophthalmol 2008;146:554-60.
- Rho DS. Treatment of acute pseudophakic cystoid macular edema: Diclofenac versus ketorolac. J Cataract Refract Surg 2003;29:2378-84.
- Laurell CG, Zetterstrom C. Effects of dexamethasone, diclofenac, or placebo on the inflammatory response after cataract surgery. Br J Ophthalmol 2002;86:1380-4.
- Missotten L, Richard C, Trinquand C. Topical 0.1% indomethacin solution versus topical 0.1% dexamethasone solution in the prevention of inflammation after cataract surgery. The Study Group. Ophthalmologica 2001;215:43-50.
- Solomon KD, Cheetham JK, DeGryse R, et al. Topical ketorolac tromethamine 0.5% ophthalmic solution in ocular inflammation after cataract surgery. Ophthalmology 2001;108:331-7.
- Miyake K, Masuda K, Shirato S, et al. Comparison of diclofenac and fluorometholone in preventing cystoid macular edema after small incision cataract surgery: a multicentered prospective trial. Jpn J Ophthalmol 2000;44:58-67.
- Herbort CP, Jauch A, Othenin-Girard P, et al. Diclofenac drops to treat inflammation after cataract surgery. Acta Ophthalmol Scand 2000;78:421-4.
- Snyder RW, Siekert RW, Schwiegerling J, et al. Acular as a single agent for use as an antimiotic and anti-inflammatory in cataract surgery. J Cataract Refract Surg 2000;26:1225-7.
- Heier JS, Topping TM, Baumann W, et al. Ketorolac versus prednisolone versus combination therapy in the treatment of acute pseudophakic cystoid macular edema. Ophthalmology 2000;107:2034-8; discussion 2039.
- Wolf EJ, Braunstein A, Shih C, Braunstein RE. Incidence of visually significant pseudophakic macular edema after uneventful phacoemulsification in patients treated with nepafenac. J Cataract Refract Surg 2007;33:1546-9.
- Asano S, Miyake K, Ota I, et al. Reducing angiographic cystoid macular edema and blood-aqueous barrier disruption after small-incision phacoemulsification and foldable intraocular lens implantation: multicenter prospective randomized comparison of topical diclofenac 0.1% and betamethasone 0.1%. J Cataract Refract Surg 2008;34:57-63.
- Almeida DR, Johnson D, Hollands H, et al. Effect of prophylactic nonsteroidal antiinflammatory drugs on cystoid macular edema assessed using optical coherence tomography quantification of total macular volume after cataract surgery. J Cataract Refract Surg 2008;34:64-9.
- Spitzer MS, Ziemssen F, Yoeruek E, et al. Efficacy of intravitreal bevacizumab in treating postoperative pseudophakic cystoid macular edema. J Cataract Refract Surg 2008;34:70-5.
- Moser CL, Martin-Baranera M, Garat M, et al. Corneal edema and intraocular pressure after cataract surgery: randomized comparison of Healon5 and Amvisc Plus. J Cataract Refract Surg 2004;30:2359-65.
- Cekic O, Batman C. Effect of intracameral carbachol on intraocular pressure following clear corneal phacoemulsification. Eye 1999;13 (Pt 2):209-11.
- Abbasoglu E, Tekeli O, Celikdogan A, Gursel E. A topical or oral carbonic anhydrase inhibitor to control ocular hypertension after cataract surgery. Eur J Ophthalmol 2000;10:27-31.
- Cetinkaya A, Akman A, Akova YA. Effect of topical brinzolamide 1% and brimonidine 0.2% on intraocular pressure after phacoemulsification. J Cataract Refract Surg 2004;30:1736-41.
- Dayanir V, Ozcura F, Kir E, et al. Medical control of intraocular pressure after phacoemulsification. J Cataract Refract Surg 2005;31:484-8.
- Ermis SS, Ozturk F, Inan UU. Comparing the effects of travoprost and brinzolamide on intraocular pressure after phacoemulsification. Eye 2005;19:303-7.
- Fry LL. Comparison of the postoperative intraocular pressure with Betagan, Betoptic, Timoptic, Iopidine, Diamox, Pilopine Gel, and Miostat. J Cataract Refract Surg 1992;18:14-9.
- Gupta A, Bansal RK, Grewal SP. Natural course of intraocular pressure after cataract extraction and the effect of intracameral carbachol. J Cataract Refract Surg 1992;18:166-9.
- Hollands RH, Drance SM, House PH, Schulzer M. Control of intraocular pressure after cataract extraction. Can J Ophthalmol 1990;25:128-32.
- Kasetti SR, Desai SP, Sivakumar S, Sunderraj P. Preventing intraocular pressure increase after phacoemulsification and the role of perioperative apraclonidine. J Cataract Refract Surg 2002;28:2177-80.
- Katsimpris JM, Siganos D, Konstas AG, et al. Efficacy of brimonidine 0.2% in controlling acute postoperative intraocular pressure elevation after phacoemulsification. J Cataract Refract Surg 2003;29:2288-94.
- Kim JY, Sohn JH, Youn DH. Effects of intracameral carbachol and acetylcholine on early postoperative intraocular pressure after cataract extraction. Korean J Ophthalmol 1994;8:61-5.
- Lai JS, Chua JK, Leung AT, Lam DS. Latanoprost versus timolol gel to prevent ocular hypertension after phacoemulsification and intraocular lens implantation. J Cataract Refract Surg 2000;26:386-91.
- Lai JS, Chua JK, Loo A, et al. Effect of intracameral acetylcholine on latanoprost in preventing ocular hypertension after phacoemulsification and intraocular lens implantation. J Cataract Refract Surg 2001;27:700-5.
- Lai JS, Loo A, Tham CC, et al. Preoperative latanoprost to prevent ocular hypertension after phacoemulsification and intraocular lens implantation. J Cataract Refract Surg 2001;27:1792-5.
- Rainer G, Menapace R, Findl O, et al. Randomised fellow eye comparison of the effectiveness of dorzolamide and apraclonidine on intraocular pressure following phacoemulsification cataract surgery. Eye 2000;14 Pt 5:757-60.
- Rainer G, Menapace R, Findl O, et al. Effect of topical brimonidine on intraocular pressure after small incision cataract surgery. J Cataract Refract Surg 2001;27:1227-31.
- Solomon KD, Stewart WC, Hunt HH, et al. Intraoperative intracameral carbachol in phacoemulsification and posterior chamber lens implantation. Am J Ophthalmol 1998;125:36-43.
- Wedrich A, Menapace R. Intraocular pressure following small-incision cataract surgery and polyHEMA posterior chamber lens implantation. A comparison between acetylcholine and carbachol. J Cataract Refract Surg 1992;18:500-5.
- Whitehouse G. Brimonidine and postoperative pressure spikes in cataract surgery. Clin Experiment Ophthalmol 2000;28:364-6.
- Kersey JP, Broadway DC. Corticosteroid-induced glaucoma: a review of the literature. Eye (Lond) 2006;20:407-16.
- Chang DF, Tan JJ, Tripodis Y. Risk factors for steroid response among cataract patients. J Cataract Refract Surg 2011;37:675-81.
- Mamalis N, Brubaker J, Davis D, et al. Complications of foldable intraocular lenses requiring explantation or secondary intervention--2007 survey update. J Cataract Refract Surg 2008;34:1584-91.
- Masket S. Pseudophakic posterior iris chafing syndrome. J Cataract Refract Surg 1986;12:252-6.
- Hayashi K, Hirata A, Hayashi H. Possible predisposing factors for in-the-bag and out-of-the-bag intraocular lens dislocation and outcomes of intraocular lens exchange surgery. Ophthalmology 2007;114:969-75.
- Jehan FS, Mamalis N, Crandall AS. Spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients. Ophthalmology 2001;108:1727-31.
- Masket S, Osher RH. Late complications with intraocular lens dislocation after capsulorhexis in pseudoexfoliation syndrome. J Cataract Refract Surg 2002;28:1481-4.
- Davis D, Brubaker J, Espandar L, et al. Late in-the-bag spontaneous intraocular lens dislocation: evaluation of 86 consecutive cases. Ophthalmology 2009;116:664-70.
- Tester R, Pace NL, Samore M, Olson RJ. Dysphotopsia in phakic and pseudophakic patients: incidence and relation to intraocular lens type(2). J Cataract Refract Surg 2000;26:810-6.
- Schwiegerling J. Recent developments in pseudophakic dysphotopsia. Curr Opin Ophthalmol 2006;17:27-30.
- Davison JA. Positive and negative dysphotopsia in patients with acrylic intraocular lenses. J Cataract Refract Surg 2000;26:1346-55.
- Coroneo MT, Pham T, Kwok LS. Off-axis edge glare in pseudophakic dysphotopsia. J Cataract Refract Surg 2003;29:1969-73.
- Osher RH. Negative dysphotopsia: long-term study and possible explanation for transient symptoms. J Cataract Refract Surg 2008;34:1699-707.
- Mamalis N. Negative dysphotopsia following cataract surgery. J Cataract Refract Surg 2010;36:371-2.
- Masket S. Truncated edge design, dysphotopsia, and inhibition of posterior capsule opacification. J Cataract Refract Surg 2000;26:145-7.
- Trattler WB, Whitsett JC, Simone PA. Negative dysphotopsia after intraocular lens implantation irrespective of design and material. J Cataract Refract Surg 2005;31:841-5.
- Narvaez J, Banning CS, Stulting RD. Negative dysphotopsia associated with implantation of the Z9000 intraocular lens. J Cataract Refract Surg 2005;31:846-7.
- Davison JA. Clinical performance of Alcon SA30AL and SA60AT single-piece acrylic intraocular lenses. J Cataract Refract Surg 2002;28:1112-23.
- Farbowitz MA, Zabriskie NA, Crandall AS, et al. Visual complaints associated with the AcrySof acrylic intraocular lens(1). J Cataract Refract Surg 2000;26:1339-45.
- Masket S, Fram NR. Pseudophakic negative dysphotopsia: Surgical management and new theory of etiology. J Cataract Refract Surg 2011;37:1199-207.
- Werner L, Apple DJ, Escobar-Gomez M, et al. Postoperative deposition of calcium on the surfaces of a hydrogel intraocular lens. Ophthalmology 2000;107:2179-85.
- Werner L, Apple DJ, Kaskaloglu M, Pandey SK. Dense opacification of the optical component of a hydrophilic acrylic intraocular lens: a clinicopathological analysis of 9 explanted lenses. J Cataract Refract Surg 2001;27:1485-92.
- Tehrani M, Mamalis N, Wallin T, et al. Late postoperative opacification of MemoryLens hydrophilic acrylic intraocular lenses: case series and review. J Cataract Refract Surg 2004;30:115-22.
- Neuhann IM, Werner L, Izak AM, et al. Late postoperative opacification of a hydrophilic acrylic (hydrogel) intraocular lens: a clinicopathological analysis of 106 explants. Ophthalmology 2004;111:2094-101.
- Hunter B, Werner L, Memmen JE, Mamalis N. Postoperative localized opacification of the new MemoryLens design: analyses of an explant. J Cataract Refract Surg 2005;31:1836-40.
- Haymore J, Zaidman G, Werner L, et al. Misdiagnosis of hydrophilic acrylic intraocular lens optic opacification: report of 8 cases with the MemoryLens. Ophthalmology 2007;114:1689-95.
- Werner L, Kollarits CR, Mamalis N, Olson RJ. Surface calcification of a 3-piece silicone intraocular lens in a patient with asteroid hyalosis: a clinicopathologic case report. Ophthalmology 2005;112:447-52.
- Wackernagel W, Ettinger K, Weitgasser U, et al. Opacification of a silicone intraocular lens caused by calcium deposits on the optic. J Cataract Refract Surg 2004;30:517-20.
- Willerscheidt AB, Healey ML, Ireland M. Cataract surgery outcomes: importance of co-morbidities in case mix. J Cataract Refract Surg 1995;21:177-81.
- Tielsch JM, Steinberg EP, Cassard SD, et al. Preoperative functional expectations and postoperative outcomes among patients undergoing first eye cataract surgery. Arch Ophthalmol 1995;113:1312-8.
- Chew EY, Sperduto RD, Milton RC, et al. Risk of advanced age-related macular degeneration after cataract surgery in the Age-Related Eye Disease Study: AREDS report number 25. Ophthalmology 2009;116:297-303.
- Dong LM, Stark WJ, Jefferys JL, et al. Progression of age-related macular degeneration after cataract surgery. Arch Ophthalmol 2009;127:1412-9.
- Takamura Y, Kubo E, Akagi Y. Analysis of the effect of intravitreal bevacizumab injection on diabetic macular edema after cataract surgery. Ophthalmology 2009;116:1151-7.
- Akinci A, Batman C, Ozkilic E, Altinsoy A. Phacoemulsification with intravitreal bevacizumab injection in diabetic patients with macular edema and cataract. Retina 2009;29:1432-5.
- Lanzagorta-Aresti A, Palacios-Pozo E, Menezo Rozalen JL, Navea-Tejerina A. Prevention of vision loss after cataract surgery in diabetic macular edema with intravitreal bevacizumab: a pilot study. Retina 2009;29:530-5.
- Cheema RA, Al-Mubarak MM, Amin YM, Cheema MA. Role of combined cataract surgery and intravitreal bevacizumab injection in preventing progression of diabetic retinopathy: prospective randomized study. J Cataract Refract Surg 2009;35:18-25.
- Lam DS, Chan CK, Mohamed S, et al. Phacoemulsification with intravitreal triamcinolone in patients with cataract and coexisting diabetic macular oedema: a 6-month prospective pilot study. Eye (Lond) 2005;19:885-90.
- Jaffe GJ, Burton TC, Kuhn E, et al. Progression of nonproliferative diabetic retinopathy and visual outcome after extracapsular cataract extraction and intraocular lens implantation. Am J Ophthalmol 1992;114:448-56.
- Chew EY, Benson WE, Remaley NA, et al. Results after lens extraction in patients with diabetic retinopathy: Early Treatment Diabetic Retinopathy Study report number 25. Arch Ophthalmol 1999;117:1600-6.
- Benson WE, Brown GC, Tasman W, et al. Extracapsular cataract extraction with placement of a posterior chamber lens in patients with diabetic retinopathy. Ophthalmology 1993;100:730-8.
- Seitzman GD, Gottsch JD, Stark WJ. Cataract surgery in patients with Fuchs' corneal dystrophy: expanding recommendations for cataract surgery without simultaneous keratoplasty. Ophthalmology 2005;112:441-6.
- Terry MA, Shamie N, Chen ES, et al. Endothelial keratoplasty for Fuchs' dystrophy with cataract: complications and clinical results with the new triple procedure. Ophthalmology 2009;116:631-9.
- Shingleton BJ, Crandall AS, Ahmed II. Pseudoexfoliation and the cataract surgeon: preoperative, intraoperative, and postoperative issues related to intraocular pressure, cataract, and intraocular lenses. J Cataract Refract Surg 2009;35:1101-20.
- Kuchle M, Viestenz A, Martus P, et al. Anterior chamber depth and complications during cataract surgery in eyes with pseudoexfoliation syndrome. Am J Ophthalmol 2000;129:281-5.
- Klein R, Klein BE, Jensen SC, Cruickshanks KJ. The relationship of ocular factors to the incidence and progression of age-related maculopathy. Arch Ophthalmol 1998;116:506-13.
- Wang JJ, Klein R, Smith W, et al. Cataract surgery and the 5-year incidence of late-stage age-related maculopathy: pooled findings from the Beaver Dam and Blue Mountains eye studies. Ophthalmology 2003;110:1960-7.
- Freeman EE, Munoz B, West SK, et al. Is there an association between cataract surgery and age-related macular degeneration? Data from three population-based studies. Am J Ophthalmol 2003;135:849-56.
- Henricsson M, Heijl A, Janzon L. Diabetic retinopathy before and after cataract surgery. Br J Ophthalmol 1996;80:789-93.
- Hayashi K, Hayashi H. Pupil size before and after phacoemulsification in nondiabetic and diabetic patients. J Cataract Refract Surg 2004;30:2543-50.
- Mittra RA, Borrillo JL, Dev S, et al. Retinopathy progression and visual outcomes after phacoemulsification in patients with diabetes mellitus. Arch Ophthalmol 2000;118:912-7.
- Squirrell D, Bhola R, Bush J, et al. A prospective, case controlled study of the natural history of diabetic retinopathy and maculopathy after uncomplicated phacoemulsification cataract surgery in patients with type 2 diabetes. Br J Ophthalmol 2002;86:565-71.
- Aiello LM, Wand M, Liang G. Neovascular glaucoma and vitreous hemorrhage following cataract surgery in patients with diabetes mellitus. Ophthalmology 1983;90:814-20.
- Henderson BA, Kim JY, Ament CS, et al. Clinical pseudophakic cystoid macular edema. Risk factors for development and duration after treatment. J Cataract Refract Surg 2007;33:1550-8.
- Green WT, Muir MG. Corneal complications of cataract surgery. Curr Opin Ophthalmol 1994;5:98-104.
- Kiessling LA, Ernest PH, Lavery KT. Scleral tunnel incision with internal corneal lip in patients with low preoperative corneal endothelial cell counts. J Cataract Refract Surg 1993;19:610-2.
- Jahn CE. Reduced intraocular pressure after phacoemulsification and posterior chamber intraocular lens implantation. J Cataract Refract Surg 1997;23:1260-4.
- Kim DD, Doyle JW, Smith MF. Intraocular pressure reduction following phacoemulsification cataract extraction with posterior chamber lens implantation in glaucoma patients. Ophthalmic Surg Lasers 1999;30:37-40.
- Barak A, Desatnik H, Ma-Naim T, et al. Early postoperative intraocular pressure pattern in glaucomatous and nonglaucomatous patients. J Cataract Refract Surg 1996;22:607-11.
- Drolsum L, Haaskjold E, Sandvig K. Phacoemulsification in eyes with pseudoexfoliation. J Cataract Refract Surg 1998;24:787-92.
- Hayashi H, Hayashi K, Nakao F, Hayashi F. Anterior capsule contraction and intraocular lens dislocation in eyes with pseudoexfoliation syndrome. Br J Ophthalmol 1998;82:1429-32.
- Scorolli L, Scorolli L, Campos EC, et al. Pseudoexfoliation syndrome: a cohort study on intraoperative complications in cataract surgery. Ophthalmologica 1998;212:278-80.
- Krolicki TJ, Tasman W. Cataract extraction in adults with retinopathy of prematurity. Arch Ophthalmol 1995;113:173-7.
- Lai YK, Fan RF. Effect of heparin-surface-modified poly(methyl methacrylate) intraocular lenses on the postoperative inflammation in an Asian population. J Cataract Refract Surg 1996;22 Suppl 1:830-4.
- Holland GN, Van Horn SD, Margolis TP. Cataract surgery with ciliary sulcus fixation of intraocular lenses in patients with uveitis. Am J Ophthalmol 1999;128:21-30.
- Okhravi N, Lightman SL, Towler HM. Assessment of visual outcome after cataract surgery in patients with uveitis. Ophthalmology 1999;106:710-22.
- Krishna R, Meisler DM, Lowder CY, et al. Long-term follow-up of extracapsular cataract extraction and posterior chamber intraocular lens implantation in patients with uveitis. Ophthalmology 1998;105:1765-9.
- Tabbara KF, Al-Kaff AS, Al-Rajhi AA, et al. Heparin surface-modified intraocular lenses in patients with inactive uveitis or diabetes. Ophthalmology 1998;105:843-5.
- Jancevski M, Foster CS. Cataracts and uveitis. Curr Opin Ophthalmol 2010;21:10-4.
- Dada T, Dhawan M, Garg S, et al. Safety and efficacy of intraoperative intravitreal injection of triamcinolone acetonide injection after phacoemulsification in cases of uveitic cataract. J Cataract Refract Surg 2007;33:1613-8.
- Goldman JM, Karp CL. Adjunct devices for managing challenging cases in cataract surgery: capsular staining and ophthalmic viscosurgical devices. Curr Opin Ophthalmol 2007;18:52-7.
- Jacobs DS, Cox TA, Wagoner MD, et al. Capsule staining as an adjunct to cataract surgery: a report from the American Academy of Ophthalmology. Ophthalmology 2006;113:707-13.
- Horiguchi M, Miyake K, Ohta I, Ito Y. Staining of the lens capsule for circular continuous capsulorrhexis in eyes with white cataract. Arch Ophthalmol 1998;116:535-7.
- Bayraktar S, Altan T, Kucuksumer Y, Yilmaz OF. Capsular tension ring implantation after capsulorhexis in phacoemulsification of cataracts associated with pseudoexfoliation syndrome. Intraoperative complications and early postoperative findings. J Cataract Refract Surg 2001;27:1620-8.
- Lee DH, Shin SC, Joo CK. Effect of a capsular tension ring on intraocular lens decentration and tilting after cataract surgery. J Cataract Refract Surg 2002;28:843-6.
- Hasanee K, Ahmed II. Capsular tension rings: update on endocapsular support devices. Ophthalmol Clin North Am 2006;19:507-19.
- Goldman JM, Karp CL. Adjunct devices for managing challenging cases in cataract surgery: pupil expansion and stabilization of the capsular bag. Curr Opin Ophthalmol 2007;18:44-51.
- Gallenga PE, Lobefalo L. Postoperative finding in the intraoperative floppy-iris syndrome. J Cataract Refract Surg 2007;33:1811-2.
- Parssinen O, Leppanen E, Keski-Rahkonen P, et al. Influence of tamsulosin on the iris and its implications for cataract surgery. Invest Ophthalmol Vis Sci 2006;47:3766-71.
- American Urological Association. Chapter 1: guideline on the management of benign prostatic hyperplasia (BPH). In: Benign Prostatic Hyperplasia (BPH) Clinical Guideline. Linthicum, MD: American Urological Association, 2010:12. Available at: www.auanet.org/content/guidelines-and-quality-care/clinical-guidelines/main-reports/bph-management/chap_1_GuidelineManagementof(BPH).pdf. Accessed June 9, 2011.
- Blouin MC, Blouin J, Perreault S, et al. Intraoperative floppy-iris syndrome associated with alpha1-adrenoreceptors: comparison of tamsulosin and alfuzosin. J Cataract Refract Surg 2007;33:1227-34.
- McCormack P, Simcock PR, Tullo AB. Management of the anticoagulated patient for ophthalmic surgery. Eye 1993;7 (Pt 6):749-50.
- Konstantatos A. Anticoagulation and cataract surgery: a review of the current literature. Anaesth Intensive Care 2001;29:11-8.
- Grines CL, Bonow RO, Casey DE Jr, et al. Prevention of premature discontinuation of dual antiplatelet therapy in patients with coronary artery stents: a science advisory from the American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, American College of Surgeons, and American Dental Association, with representation from the American College of Physicians. Circulation 2007;115:813-8.
- Katz J, Feldman MA, Bass EB, et al. Risks and benefits of anticoagulant and antiplatelet medication use before cataract surgery. Ophthalmology 2003;110:1784-8.
- Carter K, Miller KM. Phacoemulsification and lens implantation in patients treated with aspirin or warfarin. J Cataract Refract Surg 1998;24:1361-4.
- Stone LS, Kline OR, Jr, Sklar C. Intraocular lenses and anticoagulation and antiplatelet therapy. J Am Intraocul Implant Soc 1985;11:165-8.
- McMahan LB. Anticoagulants and cataract surgery. J Cataract Refract Surg 1988;14:569-71.
- Robinson GA, Nylander A. Warfarin and cataract extraction. Br J Ophthalmol 1989;73:702-3.
- Hall DL, Steen WH Jr, Drummond JW, Byrd WA. Anticoagulants and cataract surgery. Ophthalmic Surg 1988;19:221-2.
- Gainey SP, Robertson DM, Fay W, Ilstrup D. Ocular surgery on patients receiving long-term warfarin therapy. Am J Ophthalmol 1989;108:142-6.
- Roberts CW, Woods SM, Turner LS. Cataract surgery in anticoagulated patients. J Cataract Refract Surg 1991;17:309-12.
- Morris A, Elder MJ. Warfarin therapy and cataract surgery. Clin Experiment Ophthalmol 2000;28:419-22.
- Ong-Tone L, Paluck EC, Hart-Mitchell RD. Perioperative use of warfarin and aspirin in cataract surgery by Canadian Society of Cataract and Refractive Surgery members: survey. J Cataract Refract Surg 2005;31:991-6.
- Dajani AS, Taubert KA, Wilson W, et al. Prevention of bacterial endocarditis. Recommendations by the American Heart Association. Circulation 1997;96:358-66.
- Wilson W, Taubert KA, Gewitz M, et al. Prevention of infective endocarditis: guidelines from the American Heart Association: a guideline from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the Council on Clinical Cardiology, Council on Cardiovascular Surgery and Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation 2007;116:1736-54.
- American Academy of Orthopaedic Surgeons and American Association of Orthopaedic Surgeons. Clinical Guidelines and Performance Measures. Available at: www.aaos.org/research/guidelines/guide.asp. Accessed May 4, 2011.
- Vasavada A, Singh R. Step-by-step chop in situ and separation of very dense cataracts. J Cataract Refract Surg 1998;24:156-9.
- Kimura H, Kuroda S, Mizoguchi N, et al. Extracapsular cataract extraction with a sutureless incision for dense cataracts. J Cataract Refract Surg 1999;25:1275-9.
- Inatomi M, Ishii K, Koide R, et al. Intraocular lens power calculation for microphthalmos. J Cataract Refract Surg 1997;23:1208-12.
- Brockhurst RJ. Cataract surgery in nanophthalmic eyes. Arch Ophthalmol 1990;108:965-7.
- Gayton JL, Sanders VN. Implanting two posterior chamber intraocular lenses in a case of microphthalmos. J Cataract Refract Surg 1993;19:776-7.
- Fan DS, Lam DS, Li KK. Retinal complications after cataract extraction in patients with high myopia. Ophthalmology 1999;106:688-91; discussion 691-2.
- Fritch CD. Risk of retinal detachment in myopic eyes after intraocular lens implantation: a 7 year study. J Cataract Refract Surg 1998;24:1357-60.
- Alldredge CD, Elkins B, Alldredge OC, Jr. Retinal detachment following phacoemulsification in highly myopic cataract patients. J Cataract Refract Surg 1998;24:777-80.
- Lyle WA, Jin GJ. Phacoemulsification with intraocular lens implantation in high myopia. J Cataract Refract Surg 1996;22:238-42.
- Zauberman H. Extreme deepening of the anterior chamber during phacoemulsification. Ophthalmic Surg 1992;23:555-6.
- Miller KM, Keener GT Jr. Stretch pupilloplasty for small pupil phacoemulsification. Am J Ophthalmol 1994;117:107-8.
- Dinsmore SC. Modified stretch technique for small pupil phacoemulsification with topical anesthesia. J Cataract Refract Surg 1996;22:27-30.
- Fine IH. Pupilloplasty for small pupil phacoemulsification. J Cataract Refract Surg 1994;20:192-6.
- Nichamin LD. Enlarging the pupil for cataract extraction using flexible nylon iris retractors. J Cataract Refract Surg 1993;19:793-6.
- Shepherd DM. The pupil stretch technique for miotic pupils in cataract surgery. Ophthalmic Surg 1993;24:851-2.
- Guzek JP, Holm M, Cotter JB, et al. Risk factors for intraoperative complications in 1000 extracapsular cataract cases. Ophthalmology 1987;94:461-6.
- Manoj B, Chako D, Khan MY. Effect of extracapsular cataract extraction and phacoemulsification performed after trabeculectomy on intraocular pressure. J Cataract Refract Surg 2000;26:75-8.
- Chen PP, Weaver YK, Budenz DL, et al. Trabeculectomy function after cataract extraction. Ophthalmology 1998;105:1928-35.
- Caprioli J, Park HJ, Kwon YH, Weitzman M. Temporal corneal phacoemulsification in filtered glaucoma patients. Trans Am Ophthalmol Soc 1997;95:153-67; discussion 167-70.
- Seitz B, Langenbucher A, Nguyen NX, et al. Underestimation of intraocular lens power for cataract surgery after myopic photorefractive keratectomy. Ophthalmology 1999;106:693-702.
- Lyle WA, Jin GJ. Intraocular lens power prediction in patients who undergo cataract surgery following previous radial keratotomy. Arch Ophthalmol 1997;115:457-61.
- Hoffer KJ. Intraocular lens power calculation for eyes after refractive keratotomy. J Refract Surg 1995;11:490-3.
- Grusha YO, Masket S, Miller KM. Phacoemulsification and lens implantation after pars plana vitrectomy. Ophthalmology 1998;105:287-94.
- Pinter SM, Sugar A. Phacoemulsification in eyes with past pars plana vitrectomy: case-control study. J Cataract Refract Surg 1999;25:556-61.
- McDermott ML, Puklin JE, Abrams GW, Eliott D. Phacoemulsification for cataract following pars plana vitrectomy. Ophthalmic Surg Lasers 1997;28:558-64.
- Ohguro N, Matsuda M, Kinoshita S. Effects of posterior chamber lens implantation on the endothelium of transplanted corneas. Br J Ophthalmol 1997;81:1056-9.
- Tsui JY, Goins KM, Sutphin JE, Wagoner MD. Phakic descemet stripping automated endothelial keratoplasty: prevalence and prognostic impact of postoperative cataracts. Cornea 2011;30:291-5.
- Rao SK, Leung CK, Cheung CY, et al. Descemet stripping endothelial keratoplasty: effect of the surgical procedure on corneal optics. Am J Ophthalmol 2008;145:991-6.
- Eshete A, Bergwerk KL, Masket S, Miller KM. Phacoemulsification and lens implantation after scleral buckling surgery. Am J Ophthalmol 2000;129:286-90.
- Kerrison JB, Marsh M, Stark WJ, Haller JA. Phacoemulsification after retinal detachment surgery. Ophthalmology 1996;103:216-9.
- Ruiz RS, Saatci OA. Extracapsular cataract extraction with intraocular lens implantation after scleral buckling surgery. Am J Ophthalmol 1991;111:174-8.
- Vasavada A, Singh R. Phacoemulsification in eyes with posterior polar cataract. J Cataract Refract Surg 1999;25:238-45.
- Osher RH, Yu BC, Koch DD. Posterior polar cataracts: a predisposition to intraoperative posterior capsular rupture. J Cataract Refract Surg 1990;16:157-62.
- Consultation section. Cataract surgical problem. J Cataract Refract Surg 1997;23:819-24.
- Nihalani BR, Jani UD, Vasavada AR, Auffarth GU. Cataract surgery in relative anterior microphthalmos. Ophthalmology 2005;112:1360-7.
- Vajpayee RB, Bansal A, Sharma N, et al. Phacoemulsification of white hypermature cataract. J Cataract Refract Surg 1999;25:1157-60.
- Vasavada A, Singh R. Surgical techniques for difficult cataracts. Curr Opin Ophthalmol 1999;10:46-52.
- Vasavada A, Singh R, Desai J. Phacoemulsification of white mature cataracts. J Cataract Refract Surg 1998;24:270-7.
- Osher RH. Surgical management of zonular dehiscence and posterior capsular rents. J Am Intraocul Implant Soc 1983;9:186-9.
- Gimbel HV, Sun R, Heston JP. Management of zonular dialysis in phacoemulsification and IOL implantation using the capsular tension ring. Ophthalmic Surg Lasers 1997;28:273-81.
- Cionni RJ, Osher RH. Management of profound zonular dialysis or weakness with a new endocapsular ring designed for scleral fixation. J Cataract Refract Surg 1998;24:1299-306.
- Jampel HD, Friedman DS, Lubomski LH, et al. Effect of technique on intraocular pressure after combined cataract and glaucoma surgery: An evidence-based review. Ophthalmology 2002;109:2215-24.
- 67Gdih GA, Yuen D, Yan P, et al. Meta-analysis of 1- versus 2-Site Phacotrabeculectomy. Ophthalmology 2011;118:71-6.
- Wedrich A, Menapace R, Radax U, Papapanos P. Long-term results of combined trabeculectomy and small incision cataract surgery. J Cataract Refract Surg 1995;21:49-54.
- Wyse T, Meyer M, Ruderman JM, et al. Combined trabeculectomy and phacoemulsification: a one-site vs a two-site approach. Am J Ophthalmol 1998;125:334-9.
- Park HJ, Weitzman M, Caprioli J. Temporal corneal phacoemulsification combined with superior trabeculectomy. A retrospective case-control study. Arch Ophthalmol 1997;115:318-23.
- Shingleton B, Tetz M, Korber N. Circumferential viscodilation and tensioning of Schlemm canal (canaloplasty) with temporal clear corneal phacoemulsification cataract surgery for open-angle glaucoma and visually significant cataract: one-year results. J Cataract Refract Surg 2008;34:433-40.
- Francis BA, Minckler D, Dustin L, et al. Combined cataract extraction and trabeculotomy by the internal approach for coexisting cataract and open-angle glaucoma: initial results. J Cataract Refract Surg 2008;34:1096-103.
- Gayton JL, Van Der Karr M, Sanders V. Combined cataract and glaucoma surgery: trabeculectomy versus endoscopic laser cycloablation. J Cataract Refract Surg 1999;25:1214-9.
- Samuelson TW, Katz LJ, Wells JM, et al. Randomized evaluation of the trabecular micro-bypass stent with phacoemulsification in patients with glaucoma and cataract. Ophthalmology 2011;118:459-67.
- Minckler DS, Hill RA. Use of novel devices for control of intraocular pressure. Exp Eye Res 2009;88:792-8.
- Wilkins M, Indar A, Wormald R. Wilkins M, Indar A, Wormald R. Intraoperative mitomycin C for glaucoma surgery. Cochrane Database Syst Rev 2005, Issue 4. Art. No.: CD002897. DOI: 10.1002/14651858.CD002897.pub2.
- Higginbotham EJ, Stevens RK, Musch DC, et al. Bleb-related endophthalmitis after trabeculectomy with mitomycin C. Ophthalmology 1996;103:650-6.
- Greenfield DS, Suner IJ, Miller MP, et al. Endophthalmitis after filtering surgery with mitomycin. Arch Ophthalmol 1996;114:943-9.
- Jampel HD, Quigley HA, Kerrigan-Baumrind LA, et al. Risk factors for late-onset infection following glaucoma filtration surgery. Arch Ophthalmol 2001;119:1001-8.
- Zacharia PT, Deppermann SR, Schuman JS. Ocular hypotony after trabeculectomy with mitomycin C. Am J Ophthalmol 1993;116:314-26.
- Costa VP, Wilson RP, Moster MR, et al. Hypotony maculopathy following the use of topical mitomycin C in glaucoma filtration surgery. Ophthalmic Surg 1993;24:389-94.
- Greenfield DS, Liebmann JM, Jee J, Ritch R. Late-onset bleb leaks after glaucoma filtering surgery. Arch Ophthalmol 1998;116:443-7.
- Beltrame G, Salvetat ML, Driussi G, Chizzolini M. Effect of incision size and site on corneal endothelial changes in cataract surgery. J Cataract Refract Surg 2002;28:118-25.
- Ozkiris A, Arslan O, Cicik E, et al. Open-sky capsulorrhexis in triple procedure: with or without trypan blue? Eur J Ophthalmol 2003;13:764-9.
- Hayashi K, Hayashi H. Simultaneous versus sequential penetrating keratoplasty and cataract surgery. Cornea 2006;25:1020-5.
- Shimmura S, Ohashi Y, Shiroma H, et al. Corneal opacity and cataract: triple procedure versus secondary approach. Cornea 2003;22:234-8.
- Hoffer KJ. Triple procedure for intraocular lens exchange. Arch Ophthalmol 1987;105:609-10.
- Geggel HS. Intraocular lens implantation after penetrating keratoplasty. Improved unaided visual acuity, astigmatism, and safety in patients with combined corneal disease and cataract. Ophthalmology 1990;97:1460-7.
- Terry MA, Ousley PJ. Replacing the endothelium without corneal surface incisions or sutures: the first United States clinical series using the deep lamellar endothelial keratoplasty procedure. Ophthalmology 2003;110:755-64; discussion 764.
- Price FW Jr, Price MO. Descemet's stripping with endothelial keratoplasty in 200 eyes: Early challenges and techniques to enhance donor adherence. J Cataract Refract Surg 2006;32:411-8.
- Scorcia V, Matteoni S, Scorcia GB, et al. Pentacam assessment of posterior lamellar grafts to explain hyperopization after Descemet's stripping automated endothelial keratoplasty. Ophthalmology 2009;116:1651-5.
- Yoo SH, Kymionis GD, Deobhakta AA, et al. One-year results and anterior segment optical coherence tomography findings of descemet stripping automated endothelial keratoplasty combined with phacoemulsification. Arch Ophthalmol 2008;126:1052-5.
- Prasher P, Muftuoglu O, Bowman RW, et al. Corneal power measurement with a rotating Scheimpflug imaging system after Descemet-stripping automated endothelial keratoplasty. J Cataract Refract Surg 2010;36:1358-64.
- Padmanabhan P, Warade SK, Sejpal K. New endothelial keratoplasty, phacoemulsification, and intraocular lens implantation triple procedure: comparison with conventional triple procedure. J Cataract Refract Surg 2010;36:1142-8.
- Gupta PK, Bordelon A, Vroman DT, et al. Early outcomes of Descemet stripping automated endothelial keratoplasty in pseudophakic eyes with anterior chamber intraocular lenses. Am J Ophthalmol 2011;151:24-8.
- Price MO, Giebel AW, Fairchild KM, Price FW Jr. Descemet's membrane endothelial keratoplasty: prospective multicenter study of visual and refractive outcomes and endothelial survival. Ophthalmology 2009;116:2361-8.
- Sinha R, Sharma N, Vajpayee RB. Visual outcome of cataract surgery with pupillary sphincterotomy in eyes with coexisting corneal opacity. BMC Med 2004;2:10.
- Bhartiya P, Sharma N, Ray M, et al. Trypan blue assisted phacoemulsification in corneal opacities. Br J Ophthalmol 2002;86:857-9.
- Hooper PL, Rao NA, Smith RE. Cataract extraction in uveitis patients. Surv Ophthalmol 1990;35:120-44.
- Sreekantam S, Denniston AK, Murray PI. Survey of expert practice and perceptions of the supporting clinical evidence for the management of uveitis-related cataract and cystoid macular oedema. Ocul Immunol Inflamm. In press 2011.
- Belair ML, Kim SJ, Thorne JE, et al. Incidence of cystoid macular edema after cataract surgery in patients with and without uveitis using optical coherence tomography. Am J Ophthalmol 2009;148:128-35.
- Foster CS, Stavrou P, Zafirakis P, et al. Intraocular lens removal from [corrected] patients with uveitis. Am J Ophthalmol 1999;128:31-7.
- Islam MS, Vernon SA, Negi A. Intravitreal triamcinolone will cause posterior subcapsular cataract in most eyes with diabetic maculopathy within 2 years. Eye (Lond) 2007;21:321-3.
- Cekic O, Chang S, Tseng JJ, et al. Cataract progression after intravitreal triamcinolone injection. Am J Ophthalmol 2005;139:993-8.
- Galor A, Margolis R, Brasil OM, et al. Adverse events after intravitreal triamcinolone in patients with and without uveitis. Ophthalmology 2007;114:1912-8.
- Gillies MC, Simpson JM, Billson FA, et al. Safety of an intravitreal injection of triamcinolone: results from a randomized clinical trial. Arch Ophthalmol 2004;122:336-40.
- Thompson JT. Cataract formation and other complications of intravitreal triamcinolone for macular edema. Am J Ophthalmol 2006;141:629-37.
- Beck RW, Edwards AR, Aiello LP, et al, Diabetic Retinopathy Clinical Research Network (DRCR.net). Three-year follow-up of a randomized trial comparing focal/grid photocoagulation and intravitreal triamcinolone for diabetic macular edema. Arch Ophthalmol 2009;127:245-51.
- Chaudhry NA, Cohen KA, Flynn HW Jr., Murray TG. Combined pars plana vitrectomy and lens management in complex vitreoretinal disease. Semin Ophthalmol 2003;18:132-41.
- Lahey JM, Francis RR, Kearney JJ. Combining phacoemulsification with pars plana vitrectomy in patients with proliferative diabetic retinopathy: a series of 223 cases. Ophthalmology 2003;110:1335-9.
- Lahey JM, Francis RR, Kearney JJ, Cheung M. Combining phacoemulsification and vitrectomy in patients with proliferative diabetic retinopathy. Curr Opin Ophthalmol 2004;15:192-6.
- Dugas B, Ouled-Moussa R, Lafontaine PO, et al. Idiopathic epiretinal macular membrane and cataract extraction: combined versus consecutive surgery. Am J Ophthalmol 2010;149:302-6.
- MacCumber MW, Packo KH, Civantos JM, Greenberg JB. Preservation of anterior capsule during vitrectomy and lensectomy for retinal detachment with proliferative vitreoretinopathy. Ophthalmology 2002;109:329-33.
- Heiligenhaus A, Holtkamp A, Koch J, et al. Combined phacoemulsification and pars plana vitrectomy: clear corneal versus scleral incisions: prospective randomized multicenter study. J Cataract Refract Surg 2003;29:1106-12.
- Hsu SY, Wu WC. Comparison of phacoemulsification and planned extracapsular cataract extraction in combined pars plana vitrectomy and posterior chamber intraocular lens implantation. Ophthalmic Surg Lasers Imaging 2005;36:108-13.
- Wong RW, Kokame GT, Mahmoud TH, et al. Complications associated with clear corneal cataract wounds during vitrectomy. Retina 2010;30:850-5.
- Hainsworth DP, Chen SN, Cox TA, Jaffe GJ. Condensation on polymethylmethacrylate, acrylic polymer, and silicone intraocular lenses after fluid-air exchange in rabbits. Ophthalmology 1996;103:1410-8.
- Demetriades AM, Gottsch JD, Thomsen R, et al. Combined phacoemulsification, intraocular lens implantation, and vitrectomy for eyes with coexisting cataract and vitreoretinal pathology. Am J Ophthalmol 2003;135:291-6.
- Ehmann D, Garcia R. Investigating a possible cause of the myopic shift after combined cataract extraction, intraocular lens implantation, and vitrectomy for treatment of a macular hole. Can J Ophthalmol 2009;44:594-7.
- Falkner-Radler CI, Benesch T, Binder S. Accuracy of preoperative biometry in vitrectomy combined with cataract surgery for patients with epiretinal membranes and macular holes: results of a prospective controlled clinical trial. J Cataract Refract Surg 2008;34:1754-60.
- Draeger J, Schwartz R, Kohlhaas M, et al. Pressure-induced change in corneal curvature in patients with refractive surgery and unoperated probands [in German]. Ophthalmologe 1993;90:711-5.
- Behl S, Kothari K. Rupture of a radial keratotomy incision after 11 years during clear corneal phacoemulsification. J Cataract Refract Surg 2001;27:1132-4.
- Budak K, Friedman NJ, Koch DD. Dehiscence of a radial keratotomy incision during clear corneal cataract surgery. J Cataract Refract Surg 1998;24:278-80.
- Freeman M, Kumar V, Ramanathan US, O'Neill E. Dehiscence of radial keratotomy incision during phacoemulsification. Eye 2004;18:101-3.
- Koch DD, Liu JF, Hyde LL, et al. Refractive complications of cataract surgery after radial keratotomy. Am J Ophthalmol 1989;108:676-82.
- Seitz B, Langenbucher A. Intraocular lens calculations status after corneal refractive surgery. Curr Opin Ophthalmol 2000;11:35-46.
- Fang JP, Hill W, Wang L, et al. Advanced intraocular lens power calculations. In: Kohnen T, Koch DD, eds. Essentials in Ophthalmology: Cataract and Refractive Surgery. Berlin, Germany: Springer Berlin Heidelberg, 2006.
- Hill WE. Question 9: what IOL should I use in the postrefractive patient? In: Chang DF, ed. Curbside Consultation in Cataract Surgery: 49 Clinical Questions. Thorofare, NJ: SLACK Inc., 2007.
- Odenthal MT, Eggink CA, Melles G, et al. Clinical and theoretical results of intraocular lens power calculation for cataract surgery after photorefractive keratectomy for myopia. Arch Ophthalmol 2002;120:431-8.
- Argento C, Cosentino MJ, Badoza D. Intraocular lens power calculation after refractive surgery. J Cataract Refract Surg 2003;29:1346-51.
- Shammas HJ, Shammas MC, Garabet A, et al. Correcting the corneal power measurements for intraocular lens power calculations after myopic laser in situ keratomileusis. Am J Ophthalmol 2003;136:426-32.
- Stakheev AA, Balashevich LJ. Corneal power determination after previous corneal refractive surgery for intraocular lens calculation. Cornea 2003;22:214-20.
- Wang L, Booth MA, Koch DD. Comparison of intraocular lens power calculation methods in eyes that have undergone LASIK. Ophthalmology 2004;111:1825-31.
- Jarade EF, Tabbara KF. New formula for calculating intraocular lens power after laser in situ keratomileusis. J Cataract Refract Surg 2004;30:1711-5.
- Feiz V, Moshirfar M, Mannis MJ, et al. Nomogram-based intraocular lens power adjustment after myopic photorefractive keratectomy and LASIK: a new approach. Ophthalmology 2005;112:1381-7.
- Latkany RA, Chokshi AR, Speaker MG, et al. Intraocular lens calculations after refractive surgery. J Cataract Refract Surg 2005;31:562-70.
- Rosa N, Capasso L, Lanza M, et al. Reliability of a new correcting factor in calculating intraocular lens power after refractive corneal surgery. J Cataract Refract Surg 2005;31:1020-4.
- Masket S, Masket SE. Simple regression formula for intraocular lens power adjustment in eyes requiring cataract surgery after excimer laser photoablation. J Cataract Refract Surg 2006;32:430-4.
- Aramberri J. Intraocular lens power calculation after corneal refractive surgery: double-K method. J Cataract Refract Surg 2003;29:2063-8.
- Wang L, Hill WE, Koch DD. Evaluation of intraocular lens power prediction methods using the American Society of Cataract and Refractive Surgeons Post-Keratorefractive Intraocular Lens Power Calculator. J Cataract Refract Surg 2010;36:1466-73.
- Bergwerk KL, Miller KM. Outcomes of cataract surgery in monocular patients. J Cataract Refract Surg 2000;26:1631-7.
- Trotter WL, Miller KM. Outcomes of cataract extraction in functionally monocular patients. Case-control study. J Cataract Refract Surg 2002;28:1348-54.
- Pomberg ML, Miller KM. Functional visual outcomes of cataract extraction in monocular versus binocular patients. Am J Ophthalmol 2004;138:125-32.
- Rodriguez AA, Olson MD, Miller KM. Bilateral blindness in a monocular patient after cataract surgery. J Cataract Refract Surg 2005;31:438-40.
- Azen SP, Varma R, Preston-Martin S, et al. Binocular visual acuity summation and inhibition in an ocular epidemiological study: the Los Angeles Latino Eye Study. Invest Ophthalmol Vis Sci 2002;43:1742-8.
- Cagenello R, Arditi A, Halpern DL. Binocular enhancement of visual acuity. J Opt Soc Am A Opt Image Sci Vis 1993;10:1841-8.
- Derefeldt G, Lennerstrand G, Lundh B. Age variations in normal human contrast sensitivity. Acta Ophthalmol (Copenh) 1979;57:679-90.
- Home R. Binocular summation: a study of contrast sensitivity, visual acuity and recognition. Vision Res 1978;18:579-85.
- Pardhan S. A comparison of binocular summation in young and older patients. Curr Eye Res 1996;15:315-9.
- Pardhan S. Binocular performance in patients with unilateral cataract using the Regan test: binocular summation and inhibition with low-contrast charts. Eye 1993;7 (Pt 1):59-62.
- Javitt JC, Steinberg EP, Sharkey P, et al. Cataract surgery in one eye or both. A billion dollar per year issue. Ophthalmology 1995;102:1583-92; discussion 1592-3.
- Javitt JC, Brenner MH, Curbow B, et al. Outcomes of cataract surgery. Improvement in visual acuity and subjective visual function after surgery in the first, second, and both eyes. Arch Ophthalmol 1993;111:686-91.
- Lundstrom M, Stenevi U, Thorburn W. Quality of life after first- and second-eye cataract surgery: five-year data collected by the Swedish National Cataract Register. J Cataract Refract Surg 2001;27:1553-9.
- Castells X, Comas M, Alonso J, et al. In a randomized controlled trial, cataract surgery in both eyes increased benefits compared to surgery in one eye only. J Clin Epidemiol 2006;59:201-7.
- Avakian A, Temporini ER, Kara-Jose N. Second eye cataract surgery: perceptions of a population assisted at a university hospital. Clinics (Sao Paulo) 2005;60:401-6.
- Taylor RH, Misson GP, Moseley MJ. Visual acuity and contrast sensitivity in cataract: summation and inhibition of visual performance. Eye 1991;5 (Pt 6):704-7.
- Castells X, Alonso J, Ribo C, et al. Comparison of the results of first and second cataract eye surgery. Ophthalmology 1999;106:676-82.
- Laidlaw A, Harrad R. Can second eye cataract extraction be justified? Eye 1993;7 (Pt 5):680-6.
- Talbot EM, Perkins A. The benefit of second eye cataract surgery. Eye 1998;12 (Pt 6):983-9.
- Laidlaw DA, Harrad RA, Hopper CD, et al. Randomised trial of effectiveness of second eye cataract surgery. Lancet 1998;352:925-9.
- Elliott DB, Patla A, Bullimore MA. Improvements in clinical and functional vision and perceived visual disability after first and second eye cataract surgery. Br J Ophthalmol 1997;81:889-95.
- Percival SP, Vyas AV, Setty SS, Manvikar S. The influence of implant design on accuracy of postoperative refraction. Eye (Lond) 2002;16:309-15.
- Covert DJ, Henry CR, Koenig SB. Intraocular lens power selection in the second eye of patients undergoing bilateral, sequential cataract extraction. Ophthalmology 2010;117:49-54.
- Johansson BA, Lundh BL. Bilateral same day phacoemulsification: 220 cases retrospectively reviewed. Br J Ophthalmol 2003;87:285-90.
- Arshinoff SA, Strube YN, Yagev R. Simultaneous bilateral cataract surgery. J Cataract Refract Surg 2003;29:1281-91.
- Sarikkola AU, Kontkanen M, Kivela T, Laatikainen L. Simultaneous bilateral cataract surgery: a retrospective survey. J Cataract Refract Surg 2004;30:1335-41.
- Sharma TK, Worstmann T. Simultaneous bilateral cataract extraction. J Cataract Refract Surg 2001;27:741-4.
- Smith GT, Liu CS. Is it time for a new attitude to "simultaneous" bilateral cataract surgery? Br J Ophthalmol 2001;85:1489-96.
- Totan Y, Bayramlar H, Cekic O, et al. Bilateral cataract surgery in adult and pediatric patients in a single session. J Cataract Refract Surg 2000;26:1008-11.
- Kontkanen M, Kaipiainen S. Simultaneous bilateral cataract extraction: a positive view. J Cataract Refract Surg 2002;28:2060-1.
- Lundstrom M, Albrecht S, Nilsson M, Astrom B. Benefit to patients of bilateral same