The fovea avascular area (FAZ) is an area of the retina surrounded by a continuous capillary plexus that does not have any capillary structure of its own. FAZ is an important region for the formation of fine vision function. The changes of its morphology and surrounding capillary density reflect the degree of macular ischemia, and are closely related to retinal vascular diseases such as diabetic retinopathy, retinal vein occlusion, Coats disease, idiopathic macular telangiectasia, and retinopathy of prematurity. Early observation of FAZ region changes in patients with retinal vascular disease by optical coherence tomography angiography (OCTA) can evaluate the severity and prognosis of the disease. However, the measurement error of FAZ-related data is still a problem that cannot be ignored. At present, OCTA devices of various manufacturers have different methods and algorithms for measuring and analyzing FAZ, which makes it impossible to compare the measured data between different devices. It is believed that with the continuous progress of OCTA related technology, more accurate data of FAZ regional changes can be obtained, which will bring more help to clinical work.