Retro-mode Imaging for Retinal Pigment Epithelium Alterations in Central Serous Chorioretinopathy

Purpose To propose a simple, noninvasive retro-mode imaging technique employing confocal scanning laser ophthalmoscopy (cSLO) as a novel imaging modality for the detection of alterations in retinal pigment epithelium (RPE) in central serous chorioretinopathy (CSCR). Design Retrospective observational case series. Methods A total of 48 eyes from 45 patients at various phases of CSCR were included. All patients underwent spectral-domain optical coherence tomography (SD-OCT) using a volume scan protocol, fluorescein angiography (FA), indocyanine green angiography (IA), and retro-mode imaging by cSLO. We investigated retro-mode images to evaluate RPE status by comparing the results with those of SD-OCT, FA, and IA. Results Patients had various phases of CSCR: acute (23 eyes), chronic (17 eyes), and resolved (8 eyes). Retro-mode imaging detected subtle alterations in subretinal fluid (SRF) and RPE, which were undetectable with FA or IA. The correspondence between SD-OCT scanning the entire macula and retro-mode imaging differed according to the chronicity of the disease. In cases with acute CSCR, the correspondence with SD-OCT reached 44.44% in eyes with semicircular pigment epithelial detachment (PED), 33.33% in eyes with low to flat PED, and 35.71% in eyes with RPE protrusion. In cases with chronic CSCR, the correspondence with SD-OCT reached 83.33%, 57.14%, and 85.71% in eyes with semicircular PED, low to flat PED, and RPE protrusion, respectively. Correspondence in cases with resolved CSCR was 100% in eyes with either semicircular or low to flat PED and 83.33% in eyes with RPE protrusion. Conclusions Simple and noninvasive retro-mode imaging by cSLO provides improved comprehensive topographic information of RPE alterations in CSCR. Our detailed interpretation may be useful for future research of retro-mode imaging in various macular disorders.