Chorioretinal thickness and retinal pigment epithelial degeneration of fellow eyes in patients with unilateral neovascular age-related macular degeneration with subretinal drusenoid deposits

Background: We sought to investigate the chorioretinal thickness and retinal pigment epithelial (RPE) degenerative features of eyes with early age-related macular degeneration (AMD) and subretinal drusenoid deposits (SDDs) according to the presence of macular neovascularization (MNV) in the fellow eyes. Methods: We classified 70 eyes into two groups of 47 eyes with non-neovascular AMD and 23 eyes with neovascular AMD, respectively, according to the presence of MNV in the fellow eyes. The mean macular retinal, ganglion cell–inner plexiform layer (GCIPL), and choroidal thickness values and RPE features of the 6-mm-diameter zone were compared. RPE degeneration was defined as a lesion with an incomplete RPE and outer retinal atrophy (iRORA) or attenuated RPE reflectivity with diffuse basal laminar deposits, which was defined as when the eye showed an attenuated RPE line with granular features and mixed reflectivity in combination with sub-RPE deposits with a lesion ≥ 1,000 µm in length. Results: Mean retinal, GCIPL, and choroidal thickness values (286.69 ± 15.02 µm, 64.36 ± 4.21 µm, and 156.11 ± 33.10 µm) of the neovascular AMD group were greater than those (278.61 ± 13.96 µm, 61.44 ± 4.63 µm, and 133.59 ± 34.33 µm) of the non-neovascular AMD group (all P < 0.05). RPE degeneration was more prevalent in the neovascular AMD group (65.2%) than the non-neovascular AMD group (38.3%; P = 0.034). Greater mean GCIPL and choroidal thickness values and the presence of RPE degeneration were associated with type 3 MNV in fellow eyes (all P < 0.05). Conclusions: Different degenerative features according to MNV in fellow eyes of patients with AMD and SDDs suggest that variable degenerative features might be present during disease progression and have an association with the phenotype.