Alterations in the Choriocapillaris in Intermediate Age-Related Macular Degeneration

PURPOSE. The purpose of this study was to compare the choriocapillaris plexus in eyes with intermediate AMD (iAMD), with or without neovascular AMD in the fellow eye, using optical coherence tomography angiography (OCTA). METHODS. We collected data from 42 eyes with iAMD from 42 patients who had obtained OCTA. This cohort was divided into two subgroups according to the status of the fellow eye, yielding a group of 20 cases with bilateral intermediate AMD (bilateral iAMD group) and 22 cases with neovascular AMD in the fellow eye (unilateral iAMD group). An additional control group of 20 eyes from 20 healthy subjects was included for comparison. Main outcome measures were: (1) the percent of nondetectable perfused choriocapillaris area and (2) the average choriocapillaris signal void size. RESULTS. No differences in the percent of nondetectable perfused choriocapillaris area were found among the three groups (2.3 +/- 1.4% in the unilateral iAMD group, 1.5 +/- 0.9% in the bilateral iAMD group, and 1.7 6 1.4% in the control group, respectively). The average choriocapillaris signal void size, however, was significantly increased in unilateral iAMD eyes (293.7 +/- 71.2 mu m(2)) compared to both bilateral iAMD (241.5 +/- 51.6 mu m(2), P = 0.031) and control (212.7 +/- 48.6 mu m(2), P = 0.001) eyes. CONCLUSIONS. Intermediate AMD eyes of patients with neovascular AMD in the fellow eye have an increased average choriocapillaris signal void size compared to eyes without neovascular AMD in the fellow eye. If replicated in future studies, choriocapillaris signal void size may prove to be a useful parameter for evaluating eyes with AMD.