EyeNet Magazine



   
 
Journal Highlights
New Findings from Ophthalmology, AJO and Archives
 
 

July's Ophthalmology:

July's American Journal of Ophthalmology:

May's Archives of Ophthalmology:

Roundup of Other Journals:


Ophthalmology

Cytomegalovirus Anterior Uveitis in Immunocompetent Patients
July’s Ophthalmology

Van Boxtel et al. provide clinical insight into cytomegalovirus (CMV) anterior uveitis by reporting seven cases of this condition in immunocompetent individuals, each of whom presented with a different clinical manifestation.

They summarize the clinical features in two tables and describe three patients in detail. Some findings included slight iris atrophy and secondary glaucoma, secondary glaucoma without iris abnormalities and slightly elevated IOP without iris abnormalities. Polymerase chain reaction analysis of the aqueous humor showed CMV-DNA in six patients, and Goldmann-Witmer coefficients were strongly positive in four out of five patients.

The authors conclude that CMV may cause a chronic and/or recurrent anterior uveitis in otherwise healthy patients. The authors strongly recommend that, in these patients, the aqueous humor undergo analysis not only to differentiate between CMV and other herpes viruses but also to provide a definitive diagnosis in chronic anterior uveitis. They add that valganciclovir therapy may produce a significant improvement in the course of uveitis and IOP.


Complement Factor H Polymorphism Associated With Age-Related Macular Degeneration
July’s Ophthalmology

Narayanan et al. found that complement factor H (CFH) polymorphism T1277C (tyrosine-402 ---> histidine-402) is strongly associated with both dry and wet AMD.

The researchers isolated total DNA from the leukocytes of 66 AMD patients and 58 age-matched controls. They amplified the CFH gene by polymerase chain reaction and then analyzed it by Nla III restriction fragment-length analysis.

The researchers found a strong association between homozygous C and AMD compared with the control population. Compared with the control population, dry AMD also had a stronger association than wet AMD. Finally, homozygous T was more prevalent in the control individuals when compared with AMD patients. These results provide strong evidence for allele C to be a susceptibility allele for AMD.

The researchers conclude that these findings indicate a possible role of inflammation in the pathogenesis of this disease.


Vitamin Therapy for Age-Related Macular Degeneration Cost- Effective in Terms of Quality of Life
July’s Ophthalmology

Rein et al. determined that vitamin therapy composed of antioxidants and zinc for age-related macular degeneration improves quality of life in a cost-effective manner.

The researchers developed a computer model that simulated 20 million individuals age 50 and over with varied demographic characteristics, longevity and use of routine ophthalmologic care.

The model tracked patients’ costs, incidence and subsequent progression of AMD, visual impairment from AMD and quality-adjusted life years (QALYs) and followed the patients until death or age 100.

Compared with no therapy, vitamin therapy resulted in a cost-effectiveness ratio of $21,387 per QALY gained and lowered the percentage of patients with AMD who developed visual impairment in the better-seeing eye from 7 to 5.6 percent.

The researchers report that these results compared favorably to other medical therapies for preventing visual impairment from AMD.

The authors conclude that patients age 50 and older diagnosed with AMD could benefit from vitamin therapy, with the caveat that beta carotene should not be recommended to patients who smoke.


Test Differentiates Congenital From Acquired Color Vision Defects
July’s Ophthalmology

Shin et al. have identified a new computer-controlled color test that can differentiate between congenital and acquired color vision deficiency.

The color arrangement-based Seohan computerized test, which includes red and green, and yellow and blue, consists of four quadrants that contain 85 hues.

Quadrant I consists of yellow colors, quadrant II green colors, quadrant III blue colors and quadrant IV red colors. During quadrant analysis, the error scores of quadrants II and IV represent red-green color vision defects, and the error scores of quadrant I and III represent blue-yellow color vision defects.

The researchers were able to differentiate the type of color vision defect by determining which pair of quadrants had the higher error score. The investigators administered this test to 31 patients with congenital color vision deficiency and 134 patients with acquired color vision deficiency. Results showed that the quadrant analysis and ratio using the Seohan computerized hue test reliably differentiated congenital and acquired color vision deficiency with 93.3 percent sensitivity.


Travoprost and Treatment of Ocular Hypertension
July’s Ophthalmology

In a study by Robert Feldman comparing treatment alternatives for ocular hypertension, the researchers found travoprost 0.0004 percent in combination with brinzolamide 1 percent to be more efficacious than the combination of travoprost 0.0004 percent with brimonidine 0.15 percent in lowering IOP.

In this three-month, randomized, multicenter trial, patients with IOP of greater than 18 mmHg on monotherapy with the prostaglandin analogue travoprost received adjunctive therapy with twice-daily brimonidine (79 patients) or twice-daily brinzolamide (84 patients). By the third month, the mean diurnal IOP was 19.3 ± 0.27 mmHg in the brimonidine group and 18.6 ± 0.25 mmHg in the brinzolamide group, a statistically significant difference.

While the IOP-lowering effect was admittedly small and the clinical significance of these differences was unclear, the researchers conclude that these findings should be considered when evaluating the treatment alternatives for patients with glaucoma or ocular hypertension who are not effectively controlled on a prostaglandin analogue alone.


American Journal of Ophthalmology

Exudative Age-Related Macular Degeneration in Japanese Patients
July’s AJO

Maruko et al. contrasted the clinical appearance of exudative AMD in Japanese patients with previous reports in predominantly Caucasian populations.

Two hundred and eighty-nine patients with neovascular AMD were examined in a retrospective, observational, consecutive case series. The authors classified the patients into three subtypes of neovascular AMD: polypoidal choroidal vasculopathy (PCV), retinal angiomatous proliferation (RAP) and typical AMD. About 55 percent were diagnosed with PCV, 35 percent were diagnosed with typical AMD and 4.5 percent were diagnosed with RAP. In 5 percent, one eye had PCV and the other eye had typical AMD. Most patients with PCV and typical AMD had unilateral disease, with a male preponderance. Nine of 13 patients with RAP were female. Patients with RAP were older than patients with other subtypes. Serous and hemorrhagic pigment epithelial detachment developed in 44 percent with PCV, 22 percent with typical AMD and 70 percent with RAP. In the patients with unilateral disease in each subtype, large drusen in the unaffected eye were seen in 24 percent with PCV, 30 percent with typical AMD and 78 percent with RAP.

Neovascular AMD in Japanese patients has different demographic features compared with that in Caucasian patients. In Japanese patients, there is a preponderance of PCV, incidence in men, unilaterality and absence of drusen in the second eye, with the exception of RAP.


Retinal Breaks Observed During Pars Plana Vitrectomy
July’s AJO

Moore et al. examined the frequency and features of retinal breaks discovered at the time of vitrectomy and evaluated the outcomes with prophylactic treatment in a consecutive, single-surgeon, retrospective, observational case series from a two-year period.

Medical records were reviewed for all patients who underwent primary, standard, three-port pars plana vitrectomy between Jan. 1, 2000, and Dec. 31, 2001. There were 65 retinal breaks found in 48 (11.6 percent) of 415 eyes. These included 30 (7.2 percent) eyes with definite breaks, nine (2.2 percent) with suspicious breaks and nine (2.2 percent) with probably preexisting breaks. Breaks that were described as being large were more commonly associated with right-hand sclerotomy, although other categories of breaks were not. After surgery, the overall incidence of retinal detachment was 2.2 percent. The rate of retinal detachment among the 48 eyes with retinal breaks (of any category) was 2.1 percent. All retinal detachments in the series occurred more than three months after initial vitrectomy and, accordingly, were probably unrelated to retinal breaks that occurred during surgery.

Systematically looking for and treating incident breaks with retinopexy and air-fluid exchange during vitrectomy can reduce the incidence of postoperative retinal detachment to that in eyes without iatrogenic breaks.


Interferon-Alpha as Treatment for Posterior Uveitis and Panuveitis
July’s AJO

Plskova et al. evaluated whether interferon-alpha (IFN-alpha) was effective in treating patients with severe, refractory sight-threatening uveitis from a wide range of causes, including Behçet’s disease.

Twelve patients with sight-threatening uveitis that failed to respond to one or more immunosuppressive regimens were enrolled to this prospective, interventional case series. Recombinant human IFN-alpha-2b was administered subcutaneously daily, and the dose was adjusted according to the clinical response.

During the mean observation period of 11 months, a positive clinical response was observed in 83 percent of patients. Median visual acuity improved (P < 0.001) and median binocular indirect ophthalmoscopy score decreased (P < 0.05) within one month of treatment. Macular edema, if present, resolved in all patients within days of treatment. The main adverse events were tiredness, lymphopenia, flulike symptoms and transient increase of liver enzymes. Weight loss occurred in four patients. Four patients experienced depression, one of them attempting suicide. Three patients experienced typical features of IFN-alpha–associated retinopathy, which resolved on reducing the dose.

IFN-alpha seems to have significant potential in treatment of severe, sight-threatening refractory uveitis from a variety of causes. A range of adverse events, including IFN-alpha–associated retinopathy, may occur and could limit the use of this immunomodulatory drug.


Ahmed Glaucoma Valve Implantation for Uveitic Glaucoma
July’s AJO

Papadaki et al. present the long-term outcomes of Ahmed glaucoma valve implantation for uveitic glaucoma.

The authors conducted a retrospective chart review of 60 patients (60 eyes) with uveitic glaucoma who underwent Ahmed valve implantation over a four-year period. The researchers used two definitions of success. Success definition 1 included patients with IOP between 5 and 21 mmHg, reduced by 25 percent from that before implantation. Success definition 2, or qualified success, excluded those patients in whom serious complications occurred. The mean follow-up time was 30 months.

Success rates were 77 and 50 percent and qualified success rates were 57 and 39 percent at one and four years, respectively. At four years, 74 percent of the patients required glaucoma medication to maintain IOP control. The overall complication rate was 12 percent per person-years. The rate of visual acuity loss was 4 percent per person-years. The latter rate was most commonly attributed to corneal complications that were more likely to occur in patients with preoperative corneal disease.

Ahmed valve implantation seems moderately effective for the management of difficult cases of uveitic glaucoma. The success rate of the procedure drops from 77 percent at one year to 50 percent at four years, and with increasing follow-up, most patients require glaucoma medication to maintain IOP control.


Retinal Detachment in High Myopes After Phacoemulsification
July’s AJO

Alio et al. reported the incidence and risk of retinal detachment (RD) after coaxial phacoemulsification in highly myopic patients in a retrospective, consecutive, interventional study.

A total of 439 eyes from 274 highly myopic patients with spherical equivalent (SE) greater than or equal to 6 D or axial length greater than or equal to 26 mm were included. The mean age was 62.2, and the mean axial length was 27.88 mm.

The incidence of RD was 2.7 percent in these 439 eyes. RD occurred in 3.6 percent of eyes if patients were less than 50 years of age, and 2.5 percent if patients were greater than 50 years of age. Cumulative risk of RD development by Kaplan- Meier analysis in all patients was 0.5 percent, 0.7 percent, 1.7 percent, 2.6 percent and 3.3 percent at three, six, 15, 48 and 63 months until 105 months, respectively. In patients younger than 50 years of age, the risk increases to 1.2 percent at three months and 4.5 percent at 63 months until 147 months. In patients older than 50 years of age, the risk was 0.6 percent and 3 percent at six months and 52 months, respectively, until 118 months after cataract surgery. No significant correlation was found between the occurrence of RD and vitreous loss or Nd:YAG capsulotomy.

The incidence of RD in 439 highly myopic eyes after coaxial phacoemulsification is 2.7 percent. Kaplan-Meier analysis revealed a trend toward an increased risk in patients under 50 years and with axial length of greater than 28 mm when compared with patients over 50 years or with axial length less than or equal to 28 mm.


Archives of Ophthalmology

Stability of Visual Acuity Improvement Following Discontinuation of Amblyopia Treatment
May’s Archives

The Pediatric Eye Disease Investigator Group evaluated the stability of visual acuity improvement during the first year after cessation of amblyopia treatment. At the completion of a multicenter randomized trial during which amblyopia treated with patching and atropine improved by at least two lines, 80 patients aged 7 to 12 years were followed up while not receiving treatment other than spectacle wear for one year.

During the year following cessation of treatment, the cumulative probability of worsening visual acuity (of at least 2 lines) was 7 percent (95 percent confidence interval, 3 percent to 17 percent). Eighty-two percent of patients maintained an increase in visual acuity of 10 letters or more compared with their visual acuity before starting treatment.

More Online

Read the latest published research at the following Web sites:
Ophthalmology:
www.aaojournal.org
American Journal
of Ophthalmology:

www.ajo.com
Archives of Ophthalmology:
archopht.ama-assn.org

The authors conclude that visual acuity improvement occurring during amblyopia treatment is sustained in most children aged 7 to 12 for at least one year after discontinuing treatment other than spectacle wear.


Productivity of Non-MD Cataract Surgeons Trained in Eastern Africa
May’s Archives

Courtright et al. conducted a study of the productivity of cataract surgeons trained in eastern Africa. Over the past 15 years, a number of institutions in eastern Africa have trained 130 nonphysicians (generally secondary-school graduates with training as clinical officers) as cataract surgeons.

Information on aspects of active surgeons’ training, current work environment and productivity was gathered. Among the 112 active surgeons, information was obtained from 88 individuals who performed about 77,000 cataract surgeries from 2000 to 2004. Cataract surgeons have been doing, on average, 243 surgeries per year for the last five years. Factors that predicted higher productivity included current placement at an NGO or private hospital (as compared with a Ministry of Health facility), having three or more nursing support staff on their team, having two or more cataract surgical sets and having a community program that brought patients to the hospital for surgery.


Pediatric Microbial Keratitis in Taiwanese Children
May’s Archives

Hsiao et al. studied the clinical and microbiological characteristics of pediatric microbial keratitis in Taiwan to provide background information and to facilitate future prevention and treatment of pediatric microbial keratitis.

The authors conducted a retrospective review of medical records of microbial keratitis cases that occurred in children who were 16 years of age or younger and who had an initial examination at Chang Gung Memorial Hospital, one of the largest tertiary medical centers in northern Taiwan, from July 1998 through December 2002. Predisposing factors, microbial culture results, clinical course and visual outcomes were analyzed.

The most prominent predisposing factor for pediatric microbial keratitis was contact lens wear (40.7 percent of the cases), followed by trauma (21 percent). Eight of 33 contact lens wearers were enrolled in a program of overnight orthokeratology. The most common isolates were Pseudomonas aeruginosa (44.7 percent of the cases) and Staphylococcus aureus (19.1 percent). Twelve of the 81 eyes (14.8 percent) required surgical intervention. Of the 68 eyes that had BCVA available at last follow-up, 33 eyes achieved a BCVA of 20/25 or better. For those children who were not older than 8 years and had recordable vision, 11 of 22 children were at risk of amblyopia. Features seen in patients with a poor vision outcome included polymicrobial infection, fungal infection, presence of systemic disease and presence of ocular disease.

The authors conclude that the predisposing factors for childhood infectious keratitis change with age. The most predominant risk factor was contact lens wear. About one-fourth of contact lens– related corneal ulcerations were associated with overnight orthokeratology, a result worthy of special attention given the increased popularity of overnight orthokeratology.


Omega-3 Long-Chain Fatty Acid, Fish Intake and Neovascular Age-Related Macular Degeneration
May’s Archives

SanGiovanni et al. examined the relationship of fish and dietary lipid intake with early and late age-related macular degeneration in the Age-Related Eye Disease Study (AREDS).

The diets of AREDS participants aged 60 to 80 years at enrollment were analyzed to test associations of major dietary and retinal lipids with early and advanced AMD. Participants completed a validated dietary questionnaire, and photographs of their retinas were graded with a standardized protocol to determine the existence and extent of AMD. Nutritional information from 1,115 people without AMD was compared with that from 1,060 with mild AMD, 1,568 with moderate AMD, 118 with geographic atrophy and 658 with neovascular AMD. A multivariable analytic approach allowed the authors to consider whether AMD- and diet-related factors such as age, smoking and education could explain the results.

People who reported eating the highest amounts of omega-3 long-chain polyunsaturated fatty acids (LCPUFAs) or baked or broiled fish (more than one 115-g serving per week) were half to one-third less likely to have neovascular AMD than people who reported eating the lowest amounts of these nutrients and foods. Higher intake of arachidonic acid, an omega-6 fatty acid, was associated with an increased likelihood of having neovascular AMD. No other statistically significant relationships existed.

The authors conclude that omega-3 LCPUFAs or LCPUFA-rich food intake is associated with decreased likelihood of having neovascular AMD and note that these findings are supported by multiple biologically plausible mechanisms.


Association Between Vitamin D and Age-Related Macular Degeneration
May’s Archives

Parekh et al. examined the cross-sectional associations between levels of serum vitamin D and prevalent age-related macular degeneration in the Third National Health and Nutrition Examination Survey (NHANES III).

This representative sample of noninstitutionalized U.S. adults over 40 years of age included 7,752 who provided blood samples and nonmydriatic retinal photographs between 1988 and 1994. Eleven percent had early AMD and less than 1 percent had late AMD. They found that people who had levels of serum vitamin D in the highest quintile had 35 percent lower odds for early AMD compared with those in the lowest quintile.

Exploratory analyses were conducted to evaluate associations with potentially important sources of vitamin D, such as milk, fish and supplements.

Daily milk intake (compared with less than weekly use) was associated with 25 percent lower odds for early AMD. Consistent use of vitamin D from supplements (compared with nonuse) was associated with 30 percent lower odds for early AMD, but only in individuals who did not consume milk daily. Weekly fish intake was associated with 60 percent lower odds for advanced AMD.

Data were not available on sunlight exposure in NHANES III. However, in a subsample of 3,895 people who did not report abundant vitamin D from food or supplements, serum vitamin D was related to 40 percent lower odds for early AMD. This suggests that vitamin D synthesis from sunlight might help to protect against AMD. It also suggests that a protective benefit of sunlight on vitamin D synthesis might confound the observed relationships of sunlight exposure to AMD that are inconsistent in epidemiological studies.

While this study suggests the possibility that vitamin D is another of the many ingredients in food that may protect against AMD, it is the first time this association between the vitamin and disease has been reported.
___________________________

Ophthalmology summaries are written by Lori Baker Schena and edited by John Kerrison, MD. American Journal of Ophthalmology summaries are edited by Thomas J. Liesegang, MD. Archives of Ophthalmology summaries are written by the lead authors.


Roundup of Other Journals

Low-Energy Plasma Skin Regeneration Technology Apoptosis and Role of Monocyte Chemoattractant Protein
Archives of Dermatology
2007;143:168–174

In plasma skin regeneration, plasma is emitted in a millisecond pulse to deliver energy to target tissue. It has been used in dermatology as an alternative to light or radiofrequency technology.

Previous research has focused on high-energy single treatments for acne scarring or wrinkle reduction, but this approach is limited because of longer postprocedure healing periods.

In this study, Bogle et al. focused on low-energy, full-face plasma skin regeneration treatments to see if the same effect could be achieved with less downtime.

Eight volunteers underwent full-face treatments every three weeks for a total of three treatments. Results indicated a 37 percent improvement in facial rhytids three months after the low-energy treatments, compared with the 39 percent improvement seen six months after one high-energy single pass treatment. In addition, a histologic analysis following treatment confirmed production of new collagen and remodeling of dermal architecture. The treatment proved effective in improving dyspigmentation, smoothness and skin laxity associated with photoaging, and with less healing time.


Color Vision Testing in Tilted Disc Syndrome
Acta Ophthalmologica Scandinavica
Published online April 2, 2007

In this study, Vuori and Mäntyjärvi focused on color vision in patients with tilted disc syndrome to determine whether this symptom could help in the differential diagnosis of the condition. Color vision was examined using Boström-Kugelberg plates, Farnsworth-Munsell 100-hue test, Farnsworth panel D-15 test and Lanthony desaturated panel test.

The researchers examined 35 eyes of 21 patients, and found that 17 eyes (49 percent) of 11 patients had a color vision defect in at least one eye. Of the eyes with a color vision defect, a red-green defect was found in four eyes, blue defect in one eye and a mixed defect in 12 eyes. Color vision defects were not related to visual acuity or to severity of visual field defects.

This is the first report of color vision defects in tilted disc syndrome. The investigators conclude that ophthalmologists should consider color vision testing when obtaining a differential diagnosis for tilted disc syndrome. In addition, young people with tilted disc syndrome could benefit from knowing the findings of a color vision test so they can receive career guidance and be steered away from jobs that require normal color vision.


Imaging the Mouse Retina
Optics Letters
2007;32:659–661

One of the most significant obstacles to studying microscopic pathogenesis and progression of retinal disease in mice in vivo is the presence of aberrations in the rodent eye. Biss et al. found a way to address this issue by using an in vivo adaptive optics biomicroscope to compensate for aberrations, monitoring the wavefront by using the fluorescent signal from cells. The adaptive optics system incorporates a microelectromechanical system membrane mirror and a Shack-Hartmann wavefront sensor to detect the fluorescent wavefront. Through improved resolution, the authors were able to image fluorescently labeled capillary vessels and dendrites of microglia cells.

While the initial results showed marked improvement in imaging, the authors conclude that the technique could be enhanced with a deformable mirror and longer stroke, or an external doubler. They assert that this device represents an effective tool for studying the role of inflammation and/or apoptosis in the pathogenesis of diabetic retinopathy and age-related macular degeneration.
___________________________

Roundup of Other Journals is written by Lori Baker Schena and edited by Deepak P. Edward, MD.
___________________________


About Us Academy Jobs Privacy Policy Contact Us Terms of Service Medical Disclaimer Site Index