Fundus Autofluorescence (FAF) Alteration in Polypoidal Choroidal Vasculopathy (PCV) and Typical Neovascular Age Related Macular Degeneration (tAMD).

Abstract

To characterize and evaluate differences in fundus autofluorescence (FAF) alteration in polypoidal choroidal vasculopathy (PCV) and typical neovascular age related macular degeneration (tAMD). We used multimodal imaging to delineate the area of macular neovascularization (MNV) and extent of subretinal fluid (SRF). Macular FAF alteration was categorized to those limited to the area of the neovascular lesion (zone 1), area beyond zone 1 affected by subretinal fluid or pigment epithelial detachment (zone 2), and area beyond zone 2 (zone 3). Loss of FAF signal that correlated with complete outer retina and RPE loss (c-RORA) was documented. We included 94 eyes from 94 patients (48 with diagnosis of PCV; 46 with diagnosis of tAMD). PCV eyes had greater subfoveal choroidal thickness (250 ± 92 μm vs 178 ± 86 μm, p<0.001) compared to tAMD. FAF alteration was seen in all eyes in Zone 1 and 2. Polypoidal lesion(s) appear as hyper-AF, iso-AF or hypo-AF round lesions. FAF alteration extending to zone 3 was observed in 41.7% of PCV eyes and 19.6% of tAMD eyes (p=0.02), in which hyper-AF pattern was predominant. Furthermore, zone 3 FAF alteration was associated with choroidal vascular hyperpermeability in eyes with PCV but not in tAMD (40% vs 0%, p=0.03). These findings highlight RPE dysfunction may affect widespread areas in PCV, and may be the effect of choroidal congestion.