Abstract
PURPOSE: To assess choroidal vasculature in bilateral age-related macular degeneration (AMD) patients, with neovascular AMD in one eye and dry AMD in the other, using an innovative three-dimensional (3D) algorithm.
METHODS: This retrospective cross-sectional study included 30 patients with asymmetric bilateral AMD. All patients underwent clinical exams and swept-source optical coherence tomography using PlexElite-9000 (Carl Zeiss Meditec, Dublin, CA) scans centered on the fovea. The 3D choroidal vasculature was segmented using our validated deep learning algorithm. These 3D maps were divided into five sectors, with the three largest vessels in each sector selected for mean choroidal vessel diameter and inter-vessel distance (IVD) measurements. Volumetric choroidal thickness (ChT) and choroidal vascularity index (CVI) were calculated. Analysis was performed using a linear mixed model.
RESULTS: This study analyzed 60 eyes from 30 patients, with a mean age of 78.63 ± 8.01 years. Neovascular AMD eyes had significantly higher mean LogMar visual acuity (0.63 ± 0.60 vs. 0.20 ± 0.18, P < 0.001). Neovascular eyes had higher average vessel diameter (253.711 ± 20.777 vs. 232.641 ± 28.249 micrometers, P < 0.001), significant in central, temporal, and superior sectors (P < 0.05). IVD was lower in neovascular AMD (209.563 ± 21.074 vs. 213.867 ± 30.684 µm, P = 0.515). Average ChT was lower in neovascular AMD (193.939 ± 49.627 vs. 198.245 ± 53.786 µm, P = 0.809), significant in the inferior sector (P = 0.011). Additionally, CVI was higher in neovascular AMD (0.365 ± 0.033 vs. 0.353 ± 0.035, P = 0.031), particularly in inferior, superior, and central sectors (P < 0.05).
CONCLUSIONS: Eyes with neovascular AMD demonstrated higher choroidal vessel diameter, ChT, and CVI and decreased IVD compared to dry AMD eyes, possibly related to vessel congestion and inflammation in eyes with active choroidal neovascularization.