Figure 4: Representative optical coherence tomography images of the blood flow area rate of the choriocapillaris layer.

The blood flow area rate (%) of the choriocapillaris layer was measured in the full 3.0 × 3.0 mm square using built-in software. Shown are representative images before (a,c) and after (b,d) automatic binarization. (a,b) Images of an 18-year-old woman with retinitis pigmentosa with a blood flow area rate of the choriocapillaris layer of 61.8%. (c,d) Images of a 44-year-old male control with a blood flow area rate of the choriocapillaris layer of 62.3%.