Progressive Vessel Density Reduction on OCT Angiography in Glaucoma Eyes with Disc Hemorrhages

Abstract

To identify longitudinal changes in peripapillary and parafoveal vessel density (VD) measured by OCT angiography (OCTA) in primary open-angle glaucoma (POAG) eyes with disc hemorrhages (DHs). Prospective cohort study conducted from August 2016 through August 2020 PARTICIPANTS: Eighteen Asian-Indian participants with POAG (18 eyes) who sought treatment at the clinic with a single DH in the peripapillary region were recruited consecutively. The study was conducted at a tertiary eye care center. All participants who were recruited underwent a baseline OCT and OCTA, which were repeated every 4 to 6 months. Peripapillary VD and retinal nerve fiber layer (RNFL) thickness, parafoveal VD and ganglion cell-inner plexiform layer (GCIPL) thickness in the DH sector, and the corresponding mirror-image sector across the horizontal meridian (control) were evaluated over time using linear mixed-effects models. The baseline average RNFL thickness was 79 ± 9 μm. Mean duration of follow-up was 2.6 ± 0.7 years. In the DH sector, all VD and structural parameters showed a significant negative slope (P < 0.01). In the control sector, the slopes of the structural parameters (RNFL and GCIPL thickness) were not significant (P>0.05), but the rate of change of the peripapillary and parafoveal VDs were significant (P < 0.01). The rate of change of peripapillary VD was greater in the DH sector compared with the non-DH sector (-2.86 ± 0.6%/year vs. -1.71 ± 0.7%/year; P < 0.01). However, the parafoveal VD slopes did not differ significantly between DH and control sectors (-2.9 ± 0.17%/year vs. -2.8 ± 0.8%/year; P= 0.51). Eyes with POAG harboring a DH showed not only progressive RNFL and GCIPL loss in the DH sector, but also progressive peripapillary and parafoveal VD reduction in the DH and non-DH regions as documented on OCTA.