American Academy of Ophthalmology Web Site: www.aao.org
New Findings from Ophthalmology, AJO and Archives
October’s American Journal of Ophthalmology:
August’s Archives of Ophthalmology:
Roundup of Other Journals:
A study by Kim et al. characterizing the management of dislocated IOLs indicates that dislocation most commonly involves foldable IOLs. Effective treatment techniques include IOL exchange or IOL repositioning with or without scleral suture fixation.
The investigators reviewed 284 eyes of 277 patients who underwent surgery for dislocated IOLs. Three-month follow-up data were gathered from 184 eyes. Dislocated lenses included PMMA IOLs, silicone-plate IOLs, three-piece silicone IOLs and acrylic IOLs. In-the-bag dislocations were associated with pseudoexfoliation and ocular trauma. Cystoid macular edema was the most common complication of a dislocated IOL. In 11 eyes, retinal detachment occurred after management of the dislocated IOL.
The authors caution that management approaches depend upon surgeon preferences and subspecialty, yet the wide range of treatment options allows surgeons to customize the optimal treatment approach for each patient.
Findings from a two-year case-control study by Dart et al. suggest that interactions between contact lenses and the ocular surface may be more important in the development of corneal infection than oxygen levels and case contamination.
The study involved 367 contact lens wearers with presumed microbial keratitis, 1,069 contact lens wearers with disorders unrelated to contact lenses and 639 contact lens wearers randomly selected from the local area.
Compared with planned-replacement soft lenses, daily-wear disposable contact lenses had a significantly increased relative risk of microbial keratitis, rigid lenses had a reduced risk, and there was no difference for silicone-hydrogel lenses. While the risk of microbial keratitis was higher overall in daily-wear disposable lens wearers, the risk of vision loss was less for planned-replacement soft contact lens users.
The authors conclude that different brands of contact lenses may be associated with significantly different microbial keratitis risks. They hope that the findings from this study can help lead to the development of safer soft contact lenses.
While individuals with aniridia have higher-order optical aberrations associated with an increased ratio of pupillary aperture to focal length, they often experience further aberrations following cataract surgery. In 1994, the black diaphragm intraocular (BDI) lens was developed to counter these optical effects. This current study by Aslam et al. evaluated the accuracy of biometry, visual outcomes and long-term changes in 40 eyes of 35 patients with congenital and traumatic aniridia implanted with the BDI lens.
Results showed that the mean biometry prediction error was equivalent to 80 percent of target eyes being within 2 D of predicted refraction. The main complication was glaucoma, which occurred immediately after surgery—suggesting a possible direct mechanical effect of the large BDI lens. Visual outcomes were better when using the BDI lens for traumatic aniridia than for congenital aniridia.
A study by Friedman et al. of children aged 30 months through 71 months found that bilateral decreased visual acuity in Caucasian and African-American children was infrequent. They also found uncorrected ametropia to be the most common cause. The decreased visual acuity was not consistently associated with age, race or sex.
The researchers included 1,714 children out of the 2,546 in the 30-to-71-months age group of the Baltimore Pediatric Eye Disease Study. Decreased visual acuity was initially detected in 1.2 percent of Caucasian children and 1.8 percent of African-American children. After retesting within 60 days of the initial exam and with children wearing the best refractive correction, the rate of decreased visual acuity in both eyes was 0.5 percent among Caucasians and 1.1 percent among African-Americans.
In a retrospective study, Galor et al. compared the relative effectiveness and side effects of three antimetabolite agents commonly used to treat ocular inflammation—methotrexate, azathioprine and mycophenolate. They found that mycophenolate controls ocular inflammation significantly faster than methotrexate, with azathioprine demonstrating the highest rate of treatment-related side effects compared with the other two agents.
The majority of the 257 patients involved in the study were diagnosed with uveitis or scleritis. Ninety were treated with methotrexate, 38 with azathioprine and 129 with mycophenolate. The median time to treatment success was four months for the mycophenolate, 4.8 months for the azathioprine and 6.5 months for the methotrexate treatment groups.
American Journal of Ophthalmology
Wittpenn et al. evaluated whether adding perioperative topical ketorolac tromethamine 0.4 percent improves cataract surgery outcomes relative to topical steroids in patients without known risk factors for cystoid macular edema.
In this clinical trial, patients scheduled to undergo phacoemulsification surgery were randomized to receive either prednisolone acetate 1 percent or prednisolone 1 percent plus ketorolac 0.4 percent four times daily for four weeks postoperatively. In the ketorolac-steroid group, patients also received topical ketorolac 0.4 percent four times a day for three days preoperatively. In both groups, patients received four doses of ketorolac 0.4 percent one hour before surgery. Outcome measures included CME incidence, retinal thickness as measured by OCT, BCVA and contrast sensitivity.
No patients in the ketorolac-steroid group had clinically apparent CME, compared with five patients in the steroid group. No ketorolac-steroid patient had definite or probable CME, compared with six steroid patients. Mean retinal thickening was less in the ketorolac-steroid group, and fewer had retinal thickening of more than 10 µm.
Chieh et al. evaluated whether a three-year fluocinolone acetonide drug delivery system can be implanted safely at the same time that phacoemulsification and IOL implantation are performed in uveitic eyes.
This case series included 24 eyes of 21 consecutive patients with intermediate uveitis, posterior uveitis or panuveitis requiring immunosuppressive therapy, periocular corticosteroid injections or both. Phacoemulsification, IOL implantation and insertion of the fluocinolone acetonide implant were performed during a single surgical session. The main outcome measures were preoperative and postoperative ocular inflammation, visual acuity, intraoperative complications, anti-inflammatory medication use, IOP and postoperative adverse events.
No patient had intraoperative complications. The mean follow-up duration was 27 months. The mean Snellen visual acuity at baseline was 20/316, which improved significantly to 20/75 at 12 months. In the 12 months before implantation, the average number of inflammation recurrences was 2.2 episodes per eye. Only one eye experienced a recurrence at seven months after implantation. Topical corticosteroids, posterior sub-Tenon’s capsule injections and systemic anti-inflammatory medications were reduced significantly at 12 months. Average IOP was unchanged after surgery compared with preoperative IOP. Fifteen percent underwent glaucoma filtering surgery.
The authors conclude that insertion of the fluocinolone acetonide implant can be combined safely with phacoemulsification and IOL implantation during the same surgical session. Visual acuity was generally improved, while both uveitis recurrences and the need for immunosuppression decreased. The most common side effect was increased IOP.
Krohne et al. investigated intraocular concentrations and pharmacokinetics of bevacizumab after a single intravitreal injection in humans.
This case series included 30 nonvitrectomized eyes of 30 patients diagnosed with cataract and concurrent macular edema secondary to neovascular age-related macular degeneration, diabetic retinopathy or retinal venous occlusion (both in the same eye). All patients received a 1.5-mg injection of bevacizumab. Between one and 53 days after injection, an aqueous humor sample was obtained during elective cataract surgery. Concentrations of unbound bevacizumab in these samples were quantified by enzyme-linked immunosorbent assay.
The concentration of bevacizumab in aqueous humor peaked on the first day after injection with a mean concentration of 33.3 µg/ml and subsequently declined in a monoexponential fashion. Nonlinear regression analysis determined an elimination half-time of 9.82 days. No significant differences between diagnosis subgroups were noted in the study.
Jampaulo et al. evaluated the long-term rotational stability of Staar toric IOL implants from two weeks after cataract surgery until two weeks after laser posterior capsulotomy.
In this case series, 115 eyes of 72 patients were implanted with Staar toric IOLs (models AA4203TF and AA4203-TL). Forty-two of the eyes (36.5 percent) underwent laser capsulotomy because of clinically significant posterior capsular opacification. In order to document IOL axis alignment, slit-lamp retroillumination photographs were obtained in 25 eyes two weeks after cataract surgery and again two weeks after capsulotomy.
The mean difference in axis alignment before and after posterior capsulotomy was 1.36 degrees. In no case did the axis change more than five degrees. This amount is within the expected range of measurement error using a slit-lamp photographic technique for axis measurement.
The authors conclude that there are no long-term changes in this IOL’s axis orientation beyond the two-week postoperative time point. The rotational stability extends through laser posterior capsulotomy.
Archives of Ophthalmology
Kong et al. examined the postmortem eyes of a child with retinopathy of prematurity treated with intravitreal bevacizumab for zone I, stage 2 ROP.
A boy of gestational age 22 weeks suffered severe hypoxia at birth. He developed many multisystem complications throughout his life and had rapid development of bilateral zone I, stage 2 ROP. Given the persistence of fetal vasculatures and his poor clinical status, bilateral intravitreal bevacizumab injections were given on two separate occasions at doses of 0.5 mg (40 percent of the normal adult dose) instead of laser. Following the uneventful injections, ROP disappeared. He died at 50.6 weeks-postconceptual age from multiple systems failure.
Immunohistochemistry of both eyes showed no signs of toxicity or inflammation of the cornea, anterior chamber, iris, choroid, optic nerve or sclera. All the retinal layers were morphologically normal without inflammation, degeneration, extensive apoptosis or necrosis. The retinal vessels extended to medium zone II of the retina with few vascularization tufts at the junction posterior to medium zone II. Vascularization had proceeded anteriorly. VEGF expression in the retina and other ocular tissues was detected at both protein and mRNA levels.
Chauhan et al. examined the systemic and ocular risk factors for visual field progression in 258 patients. Baseline systemic measures included assessment of peripheral vasospasm and markers for hematopathology, coagulopathology and immunopathology. Patients were followed every four months with quantitative perimetric and optic-disc imaging, as well as an interventional protocol for IOP control.
After a median of 5.3 years of follow-up, the authors found four factors significantly and independently predictive of progression: abnormal baseline anticardiolipin antibody level, older age at baseline, female biological sex and mean IOP in the follow-up.
The authors conclude that while the large majority of systemic risk factors investigated in the study were not significantly predictive of progression, the role of anticardiolipin antibody levels and biological sex deserve study.
Yoo et al. examined the one-year results and anterior-segment optical coherence tomography findings in case of Descemet’s stripping automated endothelial keratoplasty (DSAEK) combined with phacoemulsification cataract and IOL surgery.
Twelve eyes of 11 patients with cataract and Fuchs’ endothelial dystrophy and at least one-year of follow-up were retrospectively reviewed. Measured variables included BCVA, refractive spherical equivalent and predictability, anterior corneal keratometric values, complications and anterior-segment OCT findings.
Data were available for all patients at one year. BCVA was unchanged (8 percent) or improved (92 percent) in all eyes compared with the preoperative levels. The authors observed a mean discrepancy between the targeted postoperative refraction and the actual postoperative spherical equivalent refraction (hyperopic shift) of 1.46 D (0.76 D). A significant correlation existed between donor corneal lenticule shape and induced hyperopic shift.
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
Sugita et al. have found that two types of polymerase chain reaction (PCR) tests are effective in detecting and analyzing the human herpes virus (HHV) in the ocular fluids of patients with uveitis.
The investigators collected 68 aqueous humor samples and 43 vitreous fluid samples from 100 patients with uveitis. They used qualitative PCR (multiplex) and quantitative PCR (real-time) tests to assay for HHV-DNA. In general, multiplex PCR can be used to detect the presence of viruses within samples, and real-time PCR can be used to measure the viral load associated with ocular HHV diseases.
The results showed that the multiplex PCR was able to detect the HHV-DNA in the ocular fluids of patients with various types of uveitis. However, the real-time PCR did a better job of measuring viral load levels of some of the ocular samples. For example, Epstein Barr virus–DNA was detected by multiplex PCR in 19 of 111 samples; however, real-time PCR analysis of Epstein Barr virus–DNA showed that only six of the 19 samples had significantly high copy numbers.
Using the Surveillance, Epidemiology and End Results (SEER) program database of the National Cancer Institute, Broaddus et al. analyzed variations in the age-adjusted incidence of retinoblastoma patients in the United States during a 30-year period between 1975 and 2004.
They found that the mean age-adjusted incidence rate of retinoblastoma was 11.8 cases per million children through age 4, a figure similar to that reported from European countries. In addition, the U.S. age-adjusted incidence rate of retinoblastoma remained stable during the 30-year study period.
Nine SEER registries covering approximately 9.5 percent of the U.S. population were utilized for the study. They identified 658 cases of retinoblastoma, which represented 6.1 percent of all cancers for children under 5 years of age. There were no sex- or race-dependent variations in the incidence of retinoblastoma.
The authors contend that it is unlikely that environmental factors such as diet or viral infection play a role in the etiology of the condition.
Ho et al. examined 6,032 participants of the population-based Rotterdam Study to investigate the relationship between cataract surgery and the risk of developing late age-related macular degeneration. The investigators used slit-lamp examination and stereoscopic color fundus photography. They also performed stratified analyses for the CFH Y402H genotype.
After adjusting for age, sex, follow-up time and the correlation between eyes, they found that prior cataract surgery was associated with incident dry, late AMD. In addition, this incidence remained significant after adjusting for smoking status and AMD stage at baseline.
They did not find any significant associations between prior cataract surgery and incidence of wet or early AMD. Homozygous CFH Y402H carriers had higher risks of all types of AMD.
Roundup of Other Journals is written by Lori Baker Schena and edited by Deepak P. Edward, MD.