Longitudinal Follow-up of Vascularized Drusen

Abstract

Purpose : To Evaluate the correlation of baseline characteristics of vascularized drusen with the risk of progression to choroidal neovascularization (CNV) using optical coherence tomography angiography (OCTA).

Methods : This was a post-hoc longitudinal analysis of eyes from the PROCON study, a 24-month masked controlled study evaluating intravitreal quarterly aflibercept for prophylaxis against conversion to exudative disease in 128 patients with intermediate non-exudative AMD in the study eye and exudative AMD in the fellow eye. OCTA B-scans were analyzed at baseline to detect eyes with vascularized drusen (presence of flow within the drusen). Eyes were graded for conversion to exudation using fluorescein angiography and structural OCT. Characteristics of vascularized drusen were evaluated at baseline and the last available visit in eyes with no conversion, or the visit immediately prior to conversion in eyes that converted.

Results : Eight vascularized drusen in 6 eyes identified by OCTA were included. Two eyes developed CNV after 15 and 9 months. In the 4 eyes with no CNV development, the mean [SD] baseline height, width, and area at the maximum height of vascularized drusen were 75.667 [11.96], 196.833 [57.41], and 0.012 [0.005] microns, respectively. In the two eyes with CNV development, the mean [SD] baseline height, width, and area at the maximum height were 88.5 [19.09], 265 [25.46], and 0.015 [0.001] microns, respectively (P-values > 0.05 for differences between two groups).
In 1 non-converted eye the vascularized druse was not detected on the follow up visit. The mean [SD] of the vascularized drusen height, width, and area at the maximum height at the 24-month follow-up in eyes with no conversion were 69.800 [8.07], 234.00 [86.28], and 0.012 [0.005] microns, respectively. These values were 90.5 [7.78], 256 [45.25], and 0.020 [0.005] microns for the two eyes with conversion (P-value = 0.03 for differences in druse height and >0.05 for width and area between two groups at follow up). No overlying retinal pigment epithelium disruption was noted over vascularized drusen on either baseline or follow up. Two drusen in eyes with conversion and three drusen from two non-converted eyes showed ellipsoid zone line disruption.

Conclusions : In this study, the 2 eyes with conversion had larger vascularized drusen at baseline. Larger studies are required to explore the association of vascularized drusen characteristics and CNV development.

This is a 2021 ARVO Annual Meeting abstract.