Evaluation of Peripapillary Vascular Density using Optical Coherence Tomography Angiography in Patients with Primary Open Angle Glaucoma

Background: Primary open-angle glaucoma (POAG) is one of the main causes of blindness all over the world. There is a rising evidence that vascular dysfunction plays a role in the pathogenesis of glaucoma. Optical coherence tomography angiography (OCTA) has emerged as a promising new technology for studying optic nerve perfusion. Purpose: To evaluating the peripapillary vascular density (pVD) in patients with POAG using the OCTA aiming at improving POAG diagnosis and management. Methods: This study was conducted as case control study which included eighty-six eyes of 45 subjects divided equally (43 eyes per group) into 2 groups, patients with POAG as study group and normal healthy individuals as control group. All patients were investigated and assessed by automated perimetry, Optical coherence tomography (OCT) and OCTA. Outcome measures involved pVD, peripapillary retinal nerve fiber layer (RNFL) thickness, mean deviation (MD), pattern standard deviation (PSD), and cup/disc (C/D) ratio. Results: There was a significant decrease in average RNFL thickness and average pVD in glaucoma group compared to normal controls group (p<0.001 and p<0.001 respectively). Linear regression analysis revealed that pVD had a significant positive correlation with RNFL thickness (p < 0.001). Additionally, a significant negative correlation existed between pVD and PSD (p < 0.001). Conclusion: pVD was significantly reduced in glaucoma patients. It could play a role in glaucoma follow up regarding disease progression and response to medication.