Changes in the area, perimeter, and circularity index of the foveal avascular zone (FAZ) can be influenced by the filling or occlusion of tiny capillaries surrounding it. In diabetic retinopathy (DR), FAZ-related indicators can provide a quantitative assessment of early DR, predict early disease changes, and offer a theoretical basis for monitoring disease progression and evaluating patients’ visual outcomes. Therefore, finding a simple and noninvasive method to visualize the FAZ has become a research hotspot in ophthalmology. The emergence of optical coherence tomography angiography (OCTA) has filled the technological gap in FAZ measurement. This article reviews the basic principles of OCTA and the clinical application of OCTA-measured FAZ-related indicators in DR, aiming to improve the diagnosis and treatment of DR.
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