To investigate the relationship between optic disc vessel density (ODVD) reduction and visual field (VF) progression in primary open-angle glaucoma (POAG) patients.

Retrospective case series.

A total of 187 POAG eyes underwent ≥5 consecutive VF, spectral-domain optical coherence tomography, and swept-source OCT angiography imaging sessions during ≥3 years of follow-up. ODVD reduction was defined as a statistically significant negative slope ( P < .05) of ODVD, calculated as the ratio of pixels occupied by vessels within the temporal optic disc area for any global, superior, or inferior sectors. The association between VF progression and rate of ODVD change was assessed by logistic regression and multivariable longitudinal linear mixed-effects models vs time.

During 3.67 ± 0.38 years of follow-up on the 187 eyes, 90 (48.1%) and 56 (29.9%) showed ODVD reduction and VF progression, respectively. A higher proportion of eyes with ODVD reduction had VF progression than did those without ODVD reduction (51/90 eyes [56.7%] vs 5/97 eyes [5.2%]; P < .001). VF progression was associated with a faster rate of global ODVD change (odds ratio, 5.10; P = .002) as well as a faster rate of global retinal nerve fiber layer thinning (odds ratio, 39.6; P = .008) in the multivariable model.

Optic disc microvasculature reduction was associated with VF progression even after adjusting for possible influencing factors including retinal nerve fiber layer thinning in POAG. This suggests that deep optic nerve head circulation has a role in the pathogenesis of glaucoma.