For a study, researchers sought to find that a total of 20 POAG eyes and 20 control eyes each were a part of the investigation. AngioPlex (Cirrus 5000 HD-OCT) was used to visualize the imaging area on the fundus using an en face view of 3 mm by 3 mm and 6 mm by 6 mm preview pictures. The topical administration of 0.5% tropicamide and 2.5% phenylephrine resulted in the creation of images both before and after. Measures of ONH perfusion, ONH flux index, macular perfusion density, macular vascular density, and foveal avascular zone (FAZ) were consecutively obtained during each session. In addition, variations in predilection and postdilation levels in POAG patients and controls were evaluated. Following tropicamide/phenylephrine instillation, POAG eyes demonstrated a statistically significant reduction in the FAZ area from a mean of 0.29-0.25 mm2 (P=0.037) and FAZ perimeter from a mean of 2.27-2.09 mm (P=0.045) in the OCTA 66 mm scan area. Measurements of ONH perfusion and ONH flow index taken before and after dilatation revealed significantly lower values in the glaucoma group compared to controls (P<0.05 for both). Following topical pupillary dilatation with 0.5% tropicamide and 2.5% phenylephrine, the FAZ area and FAZ perimeter in POAG eyes drop statistically considerably. Additional OCTA studies are needed to determine the diagnostic value of vascular changes brought on by dilated pupils in glaucoma.