Characterizing Branching Vascular Network Morphology in Polypoidal Choroidal Vasculopathy by Optical Coherence Tomography Angiography

This study analyze the morphological characteristics of branching vascular networks (BVN) in polypoidal choroidal vasculopathy (PCV) using optical coherence tomography angiography (OCTA), and correlate imaging characteristics with clinical presentations. We presented a retrospective observational case series for fifty cases of PCV confirmed by indocyanine green angiography. Macular OCTA were done by the AngioVue. The PCV cases were classified by distinct morphologic patterns of BVN by two retina specialists and clinical features were analyzed. The sensitivity of polyp detection by OCTA was 86% after manual segmentation and that of BVN was 90%. Three distinct morphologic patterns of BVN were identified. (1) The "Trunk" pattern (47%) exhibited major vessel trunk with features including presence of drusens, thin choroid, and larger BVN area. (2) The "Glomeruli" pattern (33%) showed anastomotic vascular network without major trunk. (3) The "Stick" pattern (20%) had localized BVN and the thickest choroid. Subtypes 2 and 3 held higher recurrence rate. In conclusions, the precise visualization of BVN on OCTA supported that OCTA might be a noninvasive tool to study the morphology of BVN in PCV, which exhibits three different morphological types. Identifying the morphology of BVN has the potential to prognosticate outcomes in PCV patients.