Assessment of hypofluorescent foci on late-phase indocyanine green angiography in central serous chorioretinopathy

To assess the hypofluorescent foci (HFF) on late-phase indocyanine green angiography (ICGA) in central serous chorioretinopathy (CSC) using short-wavelength fundus autofluorescence (SW-FAF), near-infrared autofluorescence (NIR-AF), and fluorescein angiography (FA). The HFF area on late-phase ICGA for at least 20 min was compared with the area of abnormal foci on SW-FAF, NIR-AF, and FA. In 14 consecutive patients (12 men, including 1 with bilateral CSC; and 2 women with unilateral CSC), four kinds of images of 27 eyes were acquired. The mean age ± standard deviation (range) was 46 ± 9.2 years (31–69 years). The HFF on late-phase ICGA were found in 23 eyes (in all 15 CSC eyes and the contralateral 8 eyes). From the results of simple regression analysis, we obtained the following three formulas. The HFF area on ICGA = 1.058 × [abnormal SW-FAF area] + 0.135, the HFF area on ICGA = 1.001 × [abnormal NIR-AF area] + 0.015, and the HFF area on ICGA = 1.089 × [abnormal FA area] + 0.135. Compared to SW-FAF and FA, NIR-AF was found to be the easiest method to detect the HFF on late-phase ICGA, which may indicate melanin abnormalities, especially a decrease, in the retinal pigment epithelium.