Long-term choroidal thickness changes based on the subtype of macular neovascularization in neovascular age-related macular degeneration (5-year follow-up)

PurposeTo evaluate the long-term choroidal thickness changes in combination with other morphological and functional outcomes during anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (nAMD) based on the subtype of macular neovascularization (MNV): MNV-1 (within the subretinal pigment epithelium space) and MNV-2 (within the subretinal space).MethodsThis retrospective study included 58 eyes from 53 patients with naive nAMD who received anti-VEGF therapy over a 60-month period. All eyes were treated initially with intravitreal bevacizumab following Pro re nata regimen. Main outcome measures included the following: subfoveal choroidal thickness (SFCT), best corrected visual acuity (BCVA), central macular thickness (CMT), development of subfoveal geographic atrophy (GA), and the number of injections.ResultsThirty-four eyes had MNV-1 (group 1) and 24 eyes had MNV-2 (group 2). SFCT in group 1 vs group 2 was (210 +/- 45 mu m vs 191 +/- 52 mu m, p = 0.01) before treatment and (170 +/- 47 mu m vs 179 +/- 48 mu m, p = 0.24) after 60 months. BCVA (log MAR) in group 1 vs group 2 was (0.57 +/- 0.18 vs 0.53 +/- 0.22, p = 0.47) before treatment and (0.59 +/- 0.23 vs 0.69 +/- 0.16, p = 0.04) after 60 months. CMT in group 1 vs group 2 was (398 +/- 154 mu m vs 382 +/- 103 mu m, p = 0.86) before treatment and (297 +/- 68 mu m vs 283 +/- 67 mu m, p = 0.14) after 60 months. The number of injections per eye over a period of 60 months was significantly higher in group 1 (34.9 +/- 11 vs 29.0 +/- 14, p = 0.04). The proportion of eyes with subfoveal GA after 60 months was significantly higher in group 2 (13 eyes, 54%) than in group 1 (9 eyes, 25%) (p = 0.03).ConclusionOver the full 60 months of anti-VEGF treatment, eyes with MNV-1 showed a greater reduction in choroidal thickness, better visual acuity, and less development of subfoveal geographic atrophy compared with eyes with MNV-2. The significantly thicker choroid in eyes with MNV type 1 at baseline seems to have a positive impact on long-term outcomes.