Progressive Optical Coherence Tomography Angiography Vessel Density Loss in Primary Open Angle Glaucoma

摘要: Purpose: Studies using Optical coherence tomography angiography (OCT-A) have shown microvascular dropout, measured as a decrease of vessel density, within the optic nerve head (ONH), the peripapillary retina and the macula in primary open angle glaucoma (POAG) eyes. This study aimed to characterize the progressive vessel density loss across different stages of the POAG continuum.Methods: Eyes from 90 glaucoma patients, who underwent more than 3 semiannual visits with both 4.5× 4.5 mm ONH and 3× 3 mm macula OCT-A imaging at each visit, were included from the Diagnostic Innovations in Glaucoma Study observational cohort study. Of the 111 glaucoma eyes, 37 had pre-perimetric glaucoma, 54 had mild glaucoma with visual field mean deviation (MD) better than-6 dB, and 20 had moderate/severe glaucoma. The rates of vessel density loss were calculated and compared using mixed effects models. The associations between the rates of vessel density loss and baseline visual field (VF) MD and baseline ONH retinal nerve fiber layer thickness (RNFLT) were evaluated.Results: The mean follow-up time and number of visits were 2.9 years and 3.9 visits for pre-perimetric glaucoma eyes, and 2.9 years and 4.0 visits for perimetric glaucoma eyes. Significant rates of vessel density loss in both ONH and macula were detectableinpre-perimetric, mild, and moderate/severe glaucoma eyes (all P< 0.05 comparing with 0 slope). The rate of vessel density loss increased with increasing severity of glaucoma, especially the perifoveal region (-0.79%/year in pre-perimetric,-1.13%/year in mild, and-1.28%/year in moderate/severe). Faster …