James Gilman

The Age-Related Eye Disease Study (AREDS): Design Implications AREDS Report No. 1

The Age-Related Eye Disease Study (AREDS) was initially conceived as a long-term multicenter, prospective study of the clinical course of age-related macular degeneration (AMD) and age-related cataract. Data on progression rates and risk factors from the study will increase understanding of the clinical course of both conditions, generate hypotheses about etiology, and aid in the design of clinical trials of potential interventions. In addition to collecting natural history data, AREDS includes a clinical trial of high-dose vitamin and mineral supplements for AMD and a clinical trial of high-dose vitamin supplements for cataract. The clinical trials were initiated largely because of the widespread public use in the United States of commercially available pharmacologic doses of vitamins and minerals to treat these two eye conditions and the absence of definitive studies on the safety and efficacy of their use. Important design issues for the clinical trials include: defining cataract and AMD, estimating event rates, determining the type and dosage of vitamins and minerals to be tested for each condition, and identifying the parameters necessary for monitoring safety and efficacy. This paper describes the AREDS design, including the study rationale and operational structure, and the approach adopted to combine, for two diseases, clinical trials with a natural history study.

The Age-Related Eye Disease Study (AREDS) system for classifying cataracts from photographs: AREDS Report No. 4

PURPOSE To describe the system for grading cataracts from photographs in the Age-Related Eye Disease Study (AREDS). METHODS The system for grading cataracts in AREDS uses photographs taken in a standardized fashion with specially modified cameras at 11 clinical centers. The photographs are evaluated by graders for quality and cataract severity at a central reading center. The area of lens involvement is used to assess the severity of cortical and posterior subcapsular opacities. Optical density of nuclear opacity is graded against a series of seven standard photographs. Contemporaneous variability in grading is evaluated periodically by having a second examiner regrade a subset of the photographs. Temporal variability is assessed by annually regrading a subset of photographs. RESULTS Photographs of 925 eyes, most with no or early lens opacities, were regraded to assess intergrader reliability. For cortical opacities, there was an absolute difference of 10% or greater of area involved in 1.9% of the replicate gradings. For posterior subcapsular opacities an absolute difference of 5% of area involved was noted in 2.8% of the regraded photographs. For nuclear opacities, absolute differences of 1.5 or more steps were observed in 0.6% of eyes. There was little evidence of temporal drift in grading any of the three types of opacity during four annual regrades. CONCLUSIONS We have demonstrated a high degree of reliability in grading the severity of lens opacities in a large study cohort with mostly early lens changes, the type of cohort most likely to be entered in clinical trials involving cataract prevention. The Age-Related Eye Disease Study System for Classifying Cataracts From Photographs could be useful in studies where there is a need to standardize data collection over time and across different data collection sites. Limitations of the system include the cost of implementation and, currently, the limited amount of data on grading reproducibility for more advanced lens opacities.

Submacular surgery trials randomized pilot trial of laser photocoagulation versus surgery for recurrent choroidal neovascularization secondary to age-related macular degeneration: I. Ophthalmic outcomes. Submacular Surgery Trials Pilot Study report number 1

PURPOSE To report complications and changes in vision during 2 years of follow-up of patients with age-related macular degeneration assigned randomly to surgical removal or to laser photocoagulation of subfoveal recurrent neovascular lesions in a pilot trial designed to test methods, to refine estimates of outcome rates, and to project patient accrual rates for a larger multicenter randomized trial to evaluate submacular surgery. PATIENTS AND METHODS Eligible patients with previous laser photocoagulation of extrafoveal or juxtafoveal choroidal neovascularization secondary to age-related macular degeneration were enrolled at 15 collaborating clinical centers. Assignments to treatment arm were made by personnel at a central coordinating center. Adherence to eligibility criteria and treatment assignment was assessed centrally at a photograph reading center. Patients were examined at 3, 6, 12, and 24 months after treatment for data collection purposes. Outcome measures reported include treatment complications, adverse events, requirements for additional treatment, and 2-year changes in visual acuity from baseline. RESULTS Of 70 patients enrolled, 36 were assigned to laser photocoagulation and 34 to submacular surgery; all were treated as assigned. One patient in each group died before the 2-year examination. Visual acuity was measured at the 2-year examination for 31 of the surviving patients (89%) in the laser arm and for 28 of the surviving patients (85%) in the surgery arm. The 2-year measurements for 36 of the 59 patients (61%) were made by an examiner masked to treatment assignment and to the identity of the study eye. Improvements and losses of visual acuity were observed in both treatment arms; 20 of 31 study eyes (65%) in the laser arm and 14 of 28 study eyes (50%) in the surgery arm had visual acuity 2 years after enrollment that was better than or no more than 1 line worse than the baseline level. Changes in visual acuity and the size of the central macular lesions from baseline to the 2-year examination were similar in the treatment arms. Few serious complications were observed in either arm at the time of initial treatment; serious adverse events were rare. During follow-up, 11 laser-treated eyes and 18 surgically treated eyes had additional intraocular procedures. CONCLUSIONS The data from this pilot trial suggest no reason to prefer submacular surgery over laser photocoagulation for treatment of patients with age-related macular degeneration who have lesions similar to those studied in this pilot trial. Any clinical trial designed to compare submacular surgery with laser photocoagulation in eyes with age-related macular degeneration and subfoveal recurrent neovascular lesions must enroll several hundred patients in order to reach a statistically valid conclusion regarding differences between these two methods of treatment with respect to either changes in visual acuity or complication rates.

Laser treatment in fellow eyes with large drusen: Updated findings from a pilot randomized clinical trial

PURPOSE To update the findings from the Choroidal Neovascularization Prevention Trial (CNVPT) with respect to resolution of drusen, incidence of choroidal neovascularization, and visual function. DESIGN A multicenter, randomized, controlled, pilot clinical trial. PARTICIPANTS The 120 patients enrolled in the CNVPT. Patients had signs of choroidal neovascularization or retinal pigment epithelial detachment in 1 eye and had >/=10 large (>63- micro m) drusen in the contralateral, or fellow, eye. INTERVENTION The fellow eye of 59 patients was assigned randomly to argon green laser treatment consisting of multiple 100- micro m spots at least 750 micro m from the center of the fovea. The fellow eye of the remaining 61 patients was assigned randomly to observation. MAIN OUTCOME MEASURES Change in visual acuity was the primary outcome measure. Incidence of choroidal neovascularization, resolution of drusen, change in contrast threshold, change in critical print size for reading, and incidence of geographic atrophy were secondary outcome measures. RESULTS Throughout 4 years of follow-up, there were no statistically significant differences in change in visual acuity, contrast threshold, critical print size, or incidence of geographic atrophy. With additional follow-up, the large increase in the incidence of choroidal neovascularization observed within 18 months of treatment was maintained; however, by 30 months, the incidence in the two treatment groups was the same. Most drusen resolution in treated eyes occurred within 24 months of the initial treatment. Treated eyes that received higher-intensity laser burns had an increased risk of choroidal neovascularization. Among eyes developing choroidal neovascularization in each treatment group, most lesions (two thirds or more) were composed of occult neovascularization only. CONCLUSIONS Laser treatment as applied in the CNVPT caused an excess risk of choroidal neovascularization in the first year or so after treatment. The increased early incidence of choroidal neovascularization was not associated with either a harmful or beneficial effect in this pilot study.

Selective Use of Indocyanine Green Angiography for Occult Choroidal Neovascularization

PURPOSE Indocyanine green angiography is useful in situations where fluorescein angiography shows occult choroidal neovascularization or pigment epithelial detachment. We sought to determine how often the selective application of indocyanine green angiography results in useful information for eyes with occult choroidal neovascularization. METHODS We reviewed 153 consecutive indocyanine green angiograms and identified 77 in which corresponding fluorescein angiograms showed occult choroidal neovascularization or pigment epithelial detachment. We examined the indocyanine green angiograms to detect areas of hyperfluorescence and to classify the margins of hyperfluorescence as well demarcated or poorly demarcated. RESULTS Of 77 eyes, 42 (55%) eyes had occult choroidal neovascularization by fluorescein angiography, seven (9%) eyes had both classic and occult choroidal neovascularization by fluorescein angiography, and 28 (36%) eyes had pigment epithelial detachments. Of 42 eyes with occult choroidal neovascularization by fluorescein angiography, 21 (50%) had well-demarcated margins, 13 (31%) had poorly demarcated margins, and eight (19%) had no detectable hyperfluorescence by indocyanine green angiography. Of seven eyes with both classic and occult choroidal neovascularization by fluorescein angiography, two had both poorly demarcated and well-demarcated borders, two had only poorly demarcated borders, and three had well-demarcated borders by indocyanine green. The indocyanine green angiogram showed 23 (82%) of 28 pigment epithelial detachments to have well-demarcated borders of hyperfluorescence; 13 (57%) of 23 were treated. CONCLUSION Indocyanine green angiography adds clinically useful information to fluorescein angiography by demonstrating well-demarcated areas of hyperfluorescence in 50% of eyes selected because of diagnosis of occult choroidal neovascularization and in 82% of eyes selected because of pigment epithelial detachment.