Comparison between thin and thick choroid eyes in central serous chorioretinopathy

Purpose: While central serous chorioretinopathy (CSCR) is typically associated with pachychoroid, a subset of patients presents with thin choroids. This study aims to compare the clinical features of CSCR in thin versus thick choroid eyes. Methods: In this retrospective multicenter study, patients were categorized by subfoveal choroidal thickness (SFCT) into thin (≤250 µm) and thick (≥400 µm) groups. Multimodal imaging was used to analyze central macular thickness (CMT), SFCT, neurosensory detachment height (NSRD-h), Haller vessel thickness (HVT), and inner choroidal thickness (ICT) at baseline and final visit. Results: Among 355 eyes, 52 (14.6%) had thin and 303 (85.4%) had thick choroids. Thin choroid patients were older (p<0.001) and more often female (38.5% vs. 23.1%,p=0.019). Visual acuity was similar at baseline (0.30 Log Minimum Angle of Resolution (logMAR), Snellen equivalent [20/40]) vs. 0.22 [20/33], p=0.38) and final follow-up (0.18 logMAR [Snellen equivalent [20/30] vs. 0.15 [20/28], p=0.08). CMT decreased in both groups, but SFCT, HVT, and ICT remained stable in the thin group. Spontaneous resolution and recurrence rates were similar; however, choroidal neovascularization (CNV) development was significantly higher in the thin choroid group (p=0.003). Conclusions: Thin-choroid CSCR represents a distinct clinical phenotype with older age, and female predominance. Although CNV occurred more frequently in this group compared to the thick choroid group, multivariate analysis indicates that age may be a key contributor to CNV risk.