Purpose: To compare choroidal hyperpermeability and vessel density between eyes with central serous chorioretinopathy (CSC), those with pachychoroid pigment epitheliopathy (PPE) and those with uncomplicated pachychoroid (UCP).
Methods: We retrospectively reviewed indocyanine green angiography images of 60 patients with unilateral active CSC who had PPE (36 eyes) or UCP (24 eyes) in their fellow eyes. We used color thresholding of indocyanine green angiography images to determine choroidal vessel density.
Results: The mean choroidal thickness of eyes with CSC was greater than that of eyes with PPE or UCP, but this difference was not statistically significant (P = 0.46). There was no significant difference between the PPE (92%) and CSC (93%) groups regarding choroidal hyperpermeability (P = 0.76), but both of these groups had higher choroidal permeability than the UCP group (50%) (both P < 0.001). In 30 (90%) of 33 eyes with PPE who had choroidal hyperpermeability, retinal pigment epithelium alterations were in the region of hyperpermeability. Choroidal vessel density did not differ between the PPE and UCP groups (P = 0.57).
Conclusion: Pachychoroid pigment epitheliopathy is forme fruste of CSC. There is no difference between complicated and UCP regarding subfoveal choroidal thickness and choroidal vessel density. The main difference between these groups is choroidal hyperpermeability.