The morphology of choroidal neovascularization in chronic central serous chorioretinopathy presenting with flat, irregular pigment epithelium detachment

PURPOSE: To evaluate morphological characteristics of choroidal neovascularization in chronic central serous chorioretinopathy (CSC) presenting with flat and irregular pigment epithelium detachment (FIPED) by means of innovative multimodal imaging. METHODS: In this observational cross-sectional study, we examined 10 consecutive patients affected by chronic CSC and FIPED using fluorescein angiography (FA), indocyanine-green angiography (ICGA) and optical coherence tomography angiography (OCTA). A qualitative analysis of the nature and characteristics of neovascular membrane was performed, combining available multimodal imaging and literature data. RESULTS: Multiple areas of retinal pigment epithelium alterations, macular hypo- and hyperpigmentation and atrophic areas were identified. Spectral domain OCT (SD-OCT) showed subretinal fluid in 80% of eyes and the ‘double layer sign’ in all patients. Late FA phases showed staining areas without leakage in all eyes; ICGA showed a hyperfluorescent plaque with surrounding hypofluorescence in 80% of patients. OCTA detected characteristic neovascular networks in the outer retina within the FIPEDs, classified as filamentous vessels with a pruned tree-like pattern in five eyes and a tangled pattern in three eyes. The choriocapillaris network showed dark areas in 80% of eyes and diffuse dark spots in all eyes. CONCLUSION: Multimodal imaging completes clinical characterization of FIPEDs in chronic CSC. This study using OCTA technology describes the phenotype of hidden neovascular lesions in shape and morphology.