Features of neovascularization in pachychoroid neovasculopathy compared with type 1 neovascular age-related macular degeneration on optical coherence tomography angiography.

Abstract

To compare neovascular membrane features of pachychoroid neovasculopathy (PNV) and type 1 neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA). Retrospective study. We assessed 34 treatment-naïve eyes with a diagnosis of PNV and 36 treatment-naïve eyes with a diagnosis of type 1 nAMD. Morphological patterns of neovascular membranes were categorized, and lesion sizes and flow areas were calculated by using en face images on the AngioVue (Optovue) OCTA system. Statistically significant differences were found between groups in age (P=0.001), baseline best corrected visual acuity (P=0.005), and baseline subfoveal choroidal thickness (P<0.001). However, there were no statistically significant differences in membrane morphology (P=0.86), lesion size (P=0.80), or flow area (P=0.96). All membranes that could be detected by OCTA could also be detected by indocyanine green angiography (ICGA). However, OCTA could not identify the neovascularization in 11.8% of the eyes with PNV and 16.7% of the eyes with nAMD, which could be identified on ICGA images. PNV is seen in younger patients and in patients with thicker choroids, but in terms of morphological characteristics and vessel density, membranes detected by OCTA are not different from those of nAMD. Dye angiography remains the gold standard for identifying neovascularization, especially in treatment-naïve patients, owing to blockage of fluid and hemorrhage and scattering of OCTA signals.