Angiographic Subtypes of Neovascular Age-related Macular Degeneration in Korean: A New Diagnostic Challenge

Neovascular age-related macular degeneration (AMD) is the leading cause of irreversible blindness in elderly population. Several classifications schemes have been developed to provide subtypes of neovascular AMD, which are known to be associated with visual prognosis. However, there is still a large proportion of patient with ambiguous findings according to current classification criteria. In this study, we classified treatment-naïve neovascular AMD patients using novel angiographic classification system and investigated the incidence and clinical characteristics of AMD subtypes. Among 339 eyes, five AMD subtypes were identified: 41 (12.1%) with classic choroidal neovascularization (CNV), 30 (8.8%) with occult CNV, 91 (26.8%) with microaneurysmal choroidal vasculopathy (MCV), 123 (36.3%) with polypoidal choroidal vasculopathy (PCV), and 54 (15.9%) with retinal angiomatous proliferation (RAP). MCV was younger than RAP (P < 0.001). Classic CNV presented with worse visual acuity compared with MCV at baseline (P < 0.001). Central macular subfield thickness was highest in RAP, and lowest in MCV (P = 0.036). Subfoveal choroidal thickness was highest in MCV, and lowest in RAP (P < 0.001). There was a significant difference in visual acuity at 12 months among five subtypes (P = 0.046). Our results highlight the importance of angiography for identifying AMD subtypes, particularly the novel MCV group being distinct from other subtypes.