Purpose: In this study, we aimed to found whether there is a difference between the primary open-angle glaucoma (POAG), pseudoexfoliative glaucoma (PXG) and pigmentary glaucoma (PG) cases, which are open-angle glaucoma types, or not, in terms of peripapillary retinal nerve fibre layer (RNFL) and peripapillary vascular density measured by optic coherence tomography angiography (OCTA).
Methods: 27 eyes of 27 patients with diagnosed POAG, 34 eyes of 34 patients with diagnosed PXG, 20 eyes of 20 patients with diagnosed PG who went to the glaucoma unit between June 2019 and January 2020 and 15 eyes of 15 healthy individuals without ocular pathology were included in our retrospective, cross-sectional study except for presbyopia in the control group and ± 1.0 D refractive error. Peripapillary RNFL measurement was performed with OCTA, and small vessel density measurements were performed with all images (AI-DD), intra-disc (ID-DD) and peripapillary (PP-DD) for the finding of vascular density in the radial peripapillary capillary network. Kruskal Wallis test and post hoc test were performed for statistical analysis.
Results: There was no statistically significant difference between the groups in terms of age and gender. AI-DD was 50.83±2.03% in the healthy group, 47.12±2.57% in primary open-angle glaucoma, 39.71± 6.64% in pseudoexfoliative glaucoma, and 43.37±1.55% in pigmentary glaucoma. ID-DD was 51.61± 3.68% in the healthy group, 49.51 ± 6.83% in primary open-angle glaucoma, 38.42±13.46% in pseudoexfoliative glaucoma, and 40.9±4.45% in pigmentary glaucoma. PP-DD was 52.62±2.65% in the healthy group, 50.13 ± 3.04% in the primary open-angle glaucoma, 42.31 ± 7.31% in the pseudoexfoliative glaucoma, and 47.6±1.40% in the pigmentary glaucoma group. While it was found that all image and intra-disc small vascular density measurements were statistically significantly lower in the pigmentary glaucoma and pseudoexfoliative glaucoma group compared to the healthy group and the primary open-angle glaucoma group (p<0.001), there was no significant difference between PXG and PG and between the control group and the POAG group.
Conclusions: Being lower radial peripapillary capillary density in PXG and PG compared to the POAG and healthy group suggests that the blood flow around the optic disc is negatively affected in these patients.