Elevated IOP is important but not the sole factor responsible for retinal ganglion cell (RGC) death and optic nerve damage in glaucoma. There is increasing evidence that visual loss correlates with macular inner retinal thinning. A total of 148 eyes from 81 patients were imaged with optical coherence tomography angiography (OCTA) in this single centre cross-sectional study. Reduced macular ganglion cell complex (GCC) thickness and blood flow was detected in eyes with glaucoma, with a statistically significant correlation with stage of glaucoma. Furthermore, visual field mean density was correlated with GCC, retinal nerve fibre layer and macular vessel density in primary open angle glaucoma. There is correlation between increased age and reducing macular vessel density (0.4% loss per year) but the decreased density is higher in eyes with glaucoma. The authors suggest that macular vessel density may be an important diagnostic parameter of glaucoma.