Longitudinal choriocapillaris changes in the presence of reticular pseudodrusen

Clemens CR, Lauermann JL, Schmitz B, Eter N, Alten F

Abstract

To determine longitudinal changes in choriocapillaris (CC) measures in eyes with reticular pseudodrusen (RPD) using optical coherence tomography angiography (OCTA). In this observational prospective study, 20 patients with exclusively RPD and no other alteration due to age-related macular degeneration were included. Eight RPD patients were re-examined at 5-year follow-up. Multimodal imaging was performed at baseline and at 5-year follow-up. OCTA CC images were analyzed for number, size and total area of flow deficits (FD), mean signal intensity, signal intensity standard deviation and kurtosis of signal intensity distribution in the ring area between a circle of 4~mm diameter and a circle of 6~mm diameter and in the superior ring quadrant. Area affected by RPD increased from 19.36 $\pm$ 8.39~mm2 at baseline to 37.77 $\pm$ 9.03~mm2 at 5-year follow-up. At baseline, percent of CC FD area was greater in RPD eyes (quadrant: p {\textless} 0.001; ring: p {\textless} 0.001) compared to controls. Besides, RPD eyes revealed a lower mean intensity signal (quadrant: p {\textless} 0.001; ring: p {\textless} 0.001). Evaluation of CC parameters suggested significant group $\times$ time interaction effects for CC FD (p = 0.04) and mean intensity signal (p = 0.004), in that RPD eyes presented increased CC FD and decreased mean intensity signal at follow-up. OCTA CC decorrelation signal further decreases in RPD patients over 5~years in both RPD-affected and RPD-unaffected macular areas.