Diurnal optic nerve head blood flow biomarker differences between male and female subjects with and without glaucoma measured by optical coherence tomography angiography

Abstract

Purpose : To examine the differences in diurnal optic nerve head (ONH) blood flow biomarkers between male and female subjects with and without open-angle glaucoma (OAG) as measured by optical coherence tomography angiography (OCT-A).

Methods : 34 subjects (21 OAG: 7 male, 14 female; and 13 healthy: 6 male, 7 female) were assessed for ONH and radial peripapillary capillary layer (RPC) flow area (mm²), vessel density percentage (NH VD%, RPC VD%), and flow index (NH index, RPC index) using OCT-A (RTVue XR Avanti SD-OCT with AngioVue® software, Optovue, Fremont, CA, USA) at 9:00, 11:00, 14:00, 16:00, and 18:00 during a single day. Results were analyzed using two-sample t-tests assuming unequal variances to analyze the differences between genders. P-value<0.05 was considered statistically significant.

Results : The OCT-A blood flow parameters were significantly lower in male OAG patients compared to female OAG patients at 18:00 (ONH flow area: 2.33<2.84mm², p=0.012; RPC flow area 1.25<1.66mm², p=0.016; NH VD% 66.55<75.67, p=0.041; NH index 0.07<0.08, p=0.05). There were no statistical significant differences between OAG male and female in RPC VD% (p=0.075) or RPC index at 18:00 (p=0.16). No other statistically significant differences were found at 9:00, 11:00, 14:00 or 16:00 time points between male and female OAG patients, or between healthy male and female subjects at any time point (p>0.05).

Conclusions : Our findings highlight possible diurnal gender-based variance in OCT-A ocular blood flow biomarkers of OAG patients, warranting further study to confirm our results.

This is a 2021 ARVO Annual Meeting abstract.