Fig. 1

This schematic representation of macular region segmentation was used in Optical Coherence Tomography (OCT) and OCT Angiography (OCTA) analysis. The top Left image shows The Early Treatment Diabetic Retinopathy Study (ETDRS) grid displays the central foveal region (F), the parafoveal quadrants (S3: superior, I3: inferior, T3: temporal, N3: nasal), and the perifoveal quadrants (S6, I6, T6, N6). The top Right image shows the zonal classification of the macula based on the distance from the foveal center: fovea (central 1 mm), parafovea (1–3 mm ring), and perifovea (3–6 mm ring). The bottom image is A cross-sectional OCT B-scan image that illustrates the segmentation of the retina into inner layers (yellow) and outer layers (blue)