Characteristics of Drusen and Bruch's membrane in postmortem eyes with age-related macular degeneration

Abstract

We performed a histopathologic study to compare eyes with different stages of age-related macular degeneration (AMD) with age-matched eyes to identify characteristics associated with exudative vs nonexudative AMD. We analyzed 51 eyes, which were obtained from an eye bank, from 40 donors with different stages of AMD and compared them with 40 age-matched control eyes. The eyes were processed for light microscopy, and the degree of calcification of Bruch's membrane, fragmentation of Bruch's membrane, the number of different types of drusen, and the presence of basal laminar (linear) deposit were assessed in the macular and extramacular regions. In the macular area, a statistically significant difference was observed for the degree of calcification (P = .02) and fragmentation (P = .03) of Bruch's membrane in eyes with exudative AMD (1.6 and 5 per eye, respectively) compared with eyes with nonexudative AMD (0.8 and 1 per eye, respectively) and control eyes (0.8 and 0 per eye, respectively). Eyes with AMD displayed notably softer, more confluent, and larger drusen and basal laminar (linear) deposit in the macular area compared with control eyes. Calcification and fragmentation of Bruch's membrane, soft, confluent, and large drusen, and basal laminar (linear) deposit but not hard drusen correlate with the histological presence of AMD. The degree of calcification and fragmentation of Bruch's membrane is greater in eyes with exudative compared with nonexudative AMD.