Choroidal vascular densities of macular disease on ultra-widefield indocyanine green angiography

Purpose: We sought to compare choroidal vascular characteristics of central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV), and age-related macular degeneration (AMD) using quantitative analyses of ultra-widefield indocyanine green (UWF ICGA) images. Methods: Eyes with CSC (n = 57), thick-choroid PCV (n = 29), thin-choroid PCV (n = 25), neovascular AMD (n = 45), and pachychoroid neovasculopathy (PNV) (n = 28) were enrolled. On UWF ICGA images, choroidal vascular density (CVD) was assessed using binarization in the total area, posterior pole, each quadrant, and vortex ampullae. Subfoveal choroidal thickness (SFCT) was measured using optical coherence tomography. Results: The CVDs of thin-choroid PCV and typical AMD were lower than those of CSC (P = 0.002 and P < 0.001, respectively; P = 0.010 and P = 0.016 when adjusted for age.), whereas the CVDs of CSC, thick-choroid PCV, and PNV did not differ from each other (all P ≥ 0.161; all P ≥ 0.424 when adjusted for age). The CVD of the total area showed a positive correlation with SFCT in each also a whole group (all P ≤ 0.001). Meanwhile, the CVD of each ampullae positively correlated with that of the corresponding quadrant in total eyes and in each group (all P ≤ 0.001). Conclusions: The mean CVD on UWF ICGA was increased in CSC, thick-choroid PCV, and PNV, whereas it was relatively low in thin-choroid PCV and typical AMD. Congestion at the vortex ampulla might be a cause of increased CVD, therefore increasing the SFCT in pachychoroid eyes.