Identifying new biomarkers associated with central visual function impairment is important in advanced glaucoma patients. This retrospective cross-sectional study enrolled 154 eyes from 154 subjects, consisting of 86 patients with advanced open-angle glaucoma (mean deviation of 24-2 visual field [VF] tests < − 15 dB) and 68 healthy controls. Structure, function, and vessel density (VD) parameters were obtained using optical coherence tomography (OCT), 24-2 standard automated perimetry, and OCT angiography, respectively. The relationships of macular thickness, central 5° and 10° VF mean sensitivity (MS), and macular VD parameters with foveal threshold (FT), representing central visual function, were investigated using partial correlation analyses and linear regression analyses, with age adjustment. Superficial and deep layer macular VD, central 5° and 10° VF MS, and best corrected visual acuity (BCVA) correlated significantly with FT after age adjustment (P < 0.05). In multivariate linear regression analyses, FT associated significantly with BCVA (β = − 8.80, P < 0.001), central 5° MS (β = 0.30, P = 0.037), and deep-layer global parafoveal VD (β = 0.37, P = 0.037). Thus, deep-layer parafoveal VD is an independent predictor of FT and may be a potential biomarker for central visual function in advanced glaucoma.

Identifying the clinical relevance of superficial versus deep layer macular vessel density (mVD) in glaucoma is important for monitoring glaucoma patients. Our current retrospective longitudinal study investigated the association of superficial and deep layer mVD parameters with glaucomatous visual field (VF) progression in mild to moderate open-angle glaucoma (OAG) eyes with central visual field (CVF) damage. Serial optical coherence tomography (OCT) angiography-derived mVD measurements were obtained in 182 mild to moderate OAG eyes (mean deviation ≥ -10 decibels). Forty-eight eyes (26.4%) showed VF progression during a mean follow-up of 3.5 years. The parafoveal and perifoveal mVDs of both superficial and deep layers showed significantly faster reduction rates in the VF progressors than in the non-progressors according to linear mixed effects models (P < 0.05). Cox and linear regression analyses showed that greater reduction rates of both the superficial layer parafoveal and perifoveal mVDs, but not their deep layer counterparts, were significant predictors of VF progression and faster VF loss (P < 0.05). In conclusion, faster rates of change in superficial but not deep layer mVD parameters are significantly associated with subsequent VF progression and faster VF deterioration in mild to moderate OAG eyes with CVF damage.