FLAT IRREGULAR PIGMENT EPITHELIUM DETACHMENT IN CENTRAL SEROUS CHORIORETINOPATHY: A Form of Pachychoroid Neovasculopathy?

Purpose: To investigate the differences in natural course, intravitreal bevacizumab injection (IVB) responsiveness, and optical coherence tomography angiography findings according to the type of pigment epithelial detachment (PED) in patients with central serous chorioretinopathy (CSC).
Methods: A retrospective review of angiographically proven CSC patients was conducted. Pigment epithelium detachment was classified as flat irregular or focal. To identify the natural course of CSC, we had observed whether subretinal fluid was improved without any treatment until symptom duration was >3 months. When CSC symptom duration was >3 months, IVB injection was performed. Symptom duration, central subfield thickness, subfoveal choroidal thickness, presence of subretinal fluid, natural course, optical coherence tomography angiography findings, and IVB responsiveness were compared between the PED types.
Results: One hundred eyes were included (64 flat irregular PED vs. 34 focal PED). Flat irregular PED had a longer symptom duration than focal PED (7.20 ± 11.52 vs. 3.69 ± 3.98 months, P = 0.03). In untreated cases, the rate of complete resolution of subretinal fluid was significantly lower in flat irregular PED than in focal PED (34.78% vs. 65.22%, P = 0.017). In contrast to the natural course, responsiveness to IVB was significantly better in flat irregular PED (72.41% vs. 31.58%, P = 0.005). Optical coherence tomography angiography revealed more CNV in flat irregular PED (42.90% vs. 10.00%, P = 0.014). Subfoveal choroidal thickness in flat irregular PED was significantly thicker.
Conclusion: In CSC patients with flat irregular PED, the natural course was poor, but treatment response to IVB was favorable. Flat irregular PED patients showed longer symptom duration and thicker subfoveal choroidal thickness than those with focal PED. Optical coherence tomography angiography revealed more choroidal neovascularization in flat irregular PED. These findings suggest that CSC with flat irregular PED could be considered a form of pachychoroid neovasculopathy.