Exploring retinal and choroidal characteristics on multimodal imaging in resolved central serous chorioretinopathy

Comparing multimodal imaging characteristics in patients with central serous chorioretinopathy (CSC) with spontaneous subretinal fluid (SRF) resolution to SRF resolution after half-dose photodynamic therapy (HD-PDT).

Forty-six patients with CSC who had spontaneous SRF resolution were compared with 46 age- and gender-matched CSC patients with SRF resolution after HD-PDT. Patients in the HD-PDT group were selected from the randomized multicentre PLACE and SPECTRA trials. In the 2 groups, differences were evaluated on fluorescein angiography (FA), indocyanine green angiography (ICGA), and fundus autofluorescence (FAF). Subfoveal choroidal thickness (SFCT), central foveal thickness (CFT), external limiting membrane (ELM) and ellipsoid zone (EZ) continuity, and pigment epithelial detachments (PEDs) were analysed on optical coherence tomography (OCT).

The median time between the last observed SRF on OCT and the resolution visit was 10.0 weeks in both groups. At the visit after SRF resolution, the area of hyperfluorescence on ICGA was larger (p = 0.001), the SFCT was thicker (p = 0.006), and EZ continuity was observed less frequently (p = 0.008) in the spontaneous SRF resolution group when compared with the HD-PDT group. No differences were observed in CFT, ELM continuity, number of PEDs, and the area of hyperfluorescence on FA.

CSC patients with spontaneous SRF resolution presumably show less favourable choroidal anatomical characteristics in the short term, compared to CSC patients with resolution after HD-PDT, as the area of ICGA hyperfluorescence was larger and the SFCT was thicker after spontaneous resolution. This observation might explain why recurrences in CSC are seen less frequently after HD-PDT.