Fig. 1. Extinction coefficient of HbO₂ and Hb at different wavelengths

Fig. 2. Fundus images at wavelengths of 570 nm and 600 nm

Fig. 3. Selection method of peripapillary ring area for the fundus functional analysis. (a) Fundus image opened with Oxymap Analyzer software; (b) delineation of ring area measurement area; (c) marked exclusionary areas; (d) selected arteries for analysis

Fig. 4. Changes in retinal arterial and venous oxygen saturation in healthy control and NDR patients

Fig. 5. Changes in retinal arterial-venous oxygen saturation differences in healthy control and NDR patients

Fig. 6. Changes in diameter of arteries and veins both in healthy control and NDR patients

Fig. 7. Difference in AVR between healthy control and NDR patients

Fig. 8. Changes in retinal foveal avascular zone area for healthy control and NDR patients