Representative images of the right eye of a 51-year-old woman with active central serous chorioretinopathy.

An optical coherence tomography image shows serous retinal detachment. The hyperpermeable region is demonstrated in indocyanine green angiography. En face images at the level of the choriocapillaris, Sattler’s layer, and Haller’s layer before and 12 months after half-fluence photodynamic therapy (HF-PDT) were adapted and converted to binary images to distinguish the vascular lumen (black area) and choroidal stroma (white area). The choroidal vascular proportion was measured as the percentage of the area of the vascular lumen against the 3.0-mm-diameter area centered at the fovea. The binarized en face images showed decreased choroidal vascular proportions at all levels 12 months after HF-PDT.