Faster Macular Vessel Density Loss in More Advanced Primary Open Angle Glaucoma Eyes

Purpose: To characterize and compare the longitudinal change of macular vessel density (VD) in primary open angle glaucoma (POAG) eyes across different disease stages. Methods: This is a sub-analysis of a prospective cohort study. A total of 103 eyes (53 eyes in the mild stage, 50 eyes in the moderate-to-advanced stage) of 75 POAG patients followed for more than 1 year with at least 2 qualified optical coherence tomography (OCT) angiography (OCTA) images were included. The rates of macular VD change were determined by linear regression and compared using the generalized linear mixed models between groups. Mixed effect models were used to evaluate the demographic and ocular parameters associated with the VD loss rate. Results: With a mean follow-up time of 2.36 years, the rates of macular VD change were significantly different from zero in both groups. The rates of macular VD loss were significantly faster in moderate-to-advanced stage group than in mild stage group in whole image (-2.46%/yr vs -1.47%/yr, p=0.002), superior hemifield (-2.42%/yr vs -1.30%/yr, p=0.001), para fovea (-2.35%/yr vs -1.26, p=0.001), superior (-2.20%/yr vs -1.01%/yr, p=0.002), nasal (-2.41%/yr vs -1.04%/yr p=0.001), inferior (-2.46%/yr vs -1.43%/yr, p=0.018) and temporal sectors (-2.32%/yr vs -1.58%/yr, p=0.012). Baseline mean deviation (MD) and OCT parameters were associated with the rates of macular VD loss. Conclusions: OCTA measurements could detect vascular deterioration over time in POAG eyes at different stages. The rates of macular VD loss were significantly faster in more advanced POAG eyes.