Abstract
Abstract: :
Purpose: To describe the 5-year incidence and change in epiretinal membranes in a defined older Australian population. Design: Population-based cohort study. Participants: 3654 persons 49 years of age or older, living in the Blue Mountains area, west of Sydney, Australia, participated in the baseline survey during 1992-94. The cohort was re-examined after 5 years in 1997-99. Excluding persons (543) who died since the baseline, 75% of survivors (n=2335) attended the follow-up examination. Methods: All participants underwent a detailed eye examination, including stereo retinal photography. Epiretinal membranes were diagnosed from grading of baseline and 5-year retinal photographs. Main Outcome Measures: Epiretinal membranes were classified as either preretinal macular fibrosis (PMF), with retinal folds, or as a less severe form, termed cellophane macular reflex (CMR), without retinal folds. Incidence of epiretinal membranes was determined if either lesion was found in eyes with no preexisting epiretinal membrane at baseline. Progression was defined if the area of involvement increased by more than 25%, regression if it decreased by more than 25% and stable if it changed by less than 25%. Results: Epiretinal membranes developed in the first eye of 107/ 2018 participants who had no sign of this condition in either eye at baseline, 5.3%, 95% confidence interval (CI) 4.4-6.4. Five-year incidence rates for PMF and CMR were 1.5% and 3.8%, respectively. Of those participants with epiretinal membranes in one eye at baseline, 18/ 133 (13.5%) developed this sign in their second eye after five years. New epiretinal membranes (mostly CMR) occurred in 15/ 165 subjects (9.1%, CI 5.2-14.6) who had undergone cataract surgery since BMES I. This rate was significantly higher than in the non-surgical group, of whom 92/ 1861 (4.9%, CI 4.0-6.0) developed epiretinal membranes. Progression from CMR to PMF was observed in 17/183 eyes (9.3%). Existing epiretinal membranes progressed, regressed or remained stable in 28.6%, 25.7% and 38.8% of eyes, respectively. Conclusion: This study has documented the 5-year incidence and the natural history of epiretinal membranes in an older population. Most epiretinal membranes did not progress over this period and we observed only a limited effect on vision.
Keywords: 352 clinical (human) or epidemiologic studies: natural history • 354 clinical (human) or epidemiologic studies: prevalence/incidence • 353 clinical (human) or epidemiologic studies: outcomes/complications