Multimodal Imaging in Fibrinous Central Serous Chorioretinopathy Compared with Exudative Maculopathy.

Aims: To analyze ocular fundus characteristics of patients finally diagnosed with fibrinous central serous chorioretinopathy (CSC) using multimodal imaging and compare the characteristics with images of other confusable exudative maculopathies.

Methods: We retrospectively reviewed the records from 189 patients with CSC and found records on 16 patients with fibrinous CSC. Some of these 16 patients were misdiagnosed with another exudative maculopathy and were treated inappropriately. Multimodal imaging comprised fundus photography, spectral-domain optical coherence tomography (OCT), fluorescein angiography (FA), indocyanine green angiography (ICGA), and OCT angiography (OCTA), and the results were compared with those of other exudative maculopathy patients from this study.

Results: Twenty-one eyes of 16 patients with a mean age of 45.44 ± 10.66 years were included in the study. The mean central choroidal thickness was 401.6 ± 47.6 μm. Eight of the 16 patients with fibrinous CSC had initially been misdiagnosed (such as with uveitis or exudative retinal detachment). On fundoscopy, a typical dark spot was seen in 19 eyes, surrounded by yellow-white exudate, corresponding to the site of leakage on FA. A hyporeflective oval-shaped vacuole-like area was observed in 14 patients. All patients showed FA signs of dye leakage and dilated choroidal vessels on ICGA. Among the patients misdiagnosed with choroidal neovascularization (CNV), OCTA showed a legible branching vessel and no signs of a blood flow signal breaking Bruch's membrane.

Conclusions: A dark spot on fundus photography images and a hyporeflective vacuole on OCT are important clinical signs that can help avoid misdiagnosing fibrinous CSC. With some small confusing lesions suspected as CNV or chronic CSC in elderly patients, OCTA may help in their identification. FA/ICGA still helps to show dye leakage sites and typical dilated choroidal vessels in fibrinous CSC, similar to other common CSCs. Multimodal imaging is mandatory in order to establish an appropriate diagnosis.