Choroidal Vascular Findings in a Case of Multifocal Geographic Atrophy: A Clinicopathologic Correlation

Purpose: We examined the choroid in both eyes from a donor with multifocal geographic atrophy (GA), enlarged choroidal vessels, and choroidal neovascularization (CNV) secondary to age-related macular degeneration, using histology and immunohistochemistry, and we correlated the findings with multimodal clinical imaging. Methods: A Caucasian woman with bilateral GA was followed clinically for 5 years, until 6 years prior to her death at age 93. To correlate clinical and histologic features, the right eyecup was photographed before dissecting the posterior pole. Choroidal blood vessels were labeled with Ulex europaeus agglutinin-1 (UEA-1) lectin following retinal pigment epithelium removal and imaged by confocal microscopy. Selected regions were embedded and sectioned for histologic staining. The left eye was used for ultrastructure analysis. Results: The posterior pole exhibited areas of atrophy surrounded by mottled retinal pigment epithelium overlying calcified drusen. Confocal imaging of the UEA-1 lectin-labeled choroidal flatmounts showed limited visualization of the submacular vasculature, consistent with masking by basal laminar and lipid-rich deposits seen in histologic sections. In well-labeled regions of the posterior pole, the choriocapillaris was attenuated and widely separated by markedly thickened, hyalinized intercapillary pillars. Venules and veins appeared dilated, and arteries exhibited arteriosclerotic changes. A choroidal neovascular complex was observed superior to the optic nerve head near the atrophic border; the adjacent choriocapillaris was attenuated. Conclusions: In this single case of multifocal GA, choroidal thickening and large-caliber outer choroidal vessels coexisted with marked choriocapillaris degeneration and adjacent neovascularization. These observations suggest that structural choroidal enlargement does not preclude choriocapillaris failure and may be associated with ischemic and neovascular phenotypes.