Abstract:AIM: To analyze the clinical and multimodal imaging characteristics of acute central serous chorioretinopathy (CSC) with or without fibrinous exudation. METHODS: Retrospective case-control study. Patients diagnosed with acute CSC with fibrinous exudation (FE group) and without fibrinous exudation (non-FE group) were consecutively included. The clinical data and multimodal images including color fundus photography, fundus autofluorescence, spectral-domain optical coherence tomography (OCT), fundus fluorescein angiography, and indocyanine green angiography at presentation were recorded. Treatment method, follow-up outcomes including best-corrected visual acuity (BCVA) and OCT characteristics were also documented. RESULTS: The FE group (n=8, 8 eyes, 6 males) had a mean age of 47.50±7.27y, and the median symptom duration was 26.50d. The non-FE group (n=20, 20 eyes, 16 males) had a mean age of 40.40±4.36y, and the median symptom duration was 7.00d. Compared to the non-FE group, the FE group exhibited significantly older age (P=0.004), longer self-reported symptom duration (P=0.02), and poorer baseline and follow-up BCVA (P=0.011, P=0.003). After more than one month follow-up, visual improvement was statistically significant in the non-FE group (P=0.017), but not in the FE group (P=0.157). Multimodal imaging results found higher prevalence of pigment epithelial detachment (PED; P=0.029) and larger subfoveal choroidal thickness (P<0.001) in the FE group, while there was no significant difference in central macular thickness between the groups. The leakage start time was earlier in the FE group (14.50±2.33s) than in the non-FE group (22.67±1.24s, P<0.001). The expanding dot sign was the most common leakage pattern of fibrinous CSC. Late leakage area usually expanded to more than 1/2 disc diameter (DD) in the FE group, while it was less than 1/2 DD in the non-FE group. CONCLUSION: Fibrinous exudation in acute CSC is a multimodal imaging biomarker indicative of severe choroidal vasculopathy and retinal pigment epithelium barrier failure. Recognizing this entity and understanding its potential mechanisms are crucial for managing patient prognosis and may guide future targeted interventions.
