Hondur G, et al. - In this cross-sectional study, researchers sought to compare the peripapillary vessel density (VD), peripapillary retinal nerve fiber layer (RNFL) thickness, and optic nerve head (ONH) parameters between eyes with atrophic non-arteritic anterior ischemic optic neuropathy (NAION) and eyes with advanced primary open-angle glaucoma (POAG) matched for visual field mean deviation. Optical coherence tomography angiography (OCTA) was used to assess peripapillary VDs and RNFL thicknesses in the peripapillary region, as well as 4 sectors (superior, inferior, nasal, and temporal), and scanning laser ophthalmoscopy parameters of the ONH in 21 atrophic NAION cases, 26 advanced POAG cases, and 30 age- and sex-matched healthy controls. Findings suggested that a tendency for a lower peripapillary VD despite similar visual field mean deviation values may infer a more prominent role of the vascular regression in POAG vs NAION.