Flat irregular pigment epithelium detachments in chronic central serous chorioretinopathy: a focus on choroidal changes.

OBJECTIVE

To investigate the choroidal features associated with the presence of flat irregular pigment epithelium detachments (FIPEDs) in patients with previous diagnosis of chronic central serous chorioretinopathy (CSC).

METHODS

This was a retrospective multicentric study that analysed the medical records and imaging findings of 199 patients with treated and untreated, chronic CSC. The diagnosis was established by multimodal imaging. Eyes with macular FIPEDs, defined as an irregular elevation of the RPE under which the Bruch's membrane (BM) could be evident on structural optical coherence tomography (OCT) cross-sectional B-scans, were enrolled. OCT images were graded for the presence of dilated Haller vessels (pachyvessels) "compressing" and attenuating choriocapillaris and Sattler layer thickness beneath the FIPED. The presence of macular neovascularisation (MNV) was determined using indocyanine green angiography (ICGA) or OCT angiography imaging. FIPEDs were categorised as vascular (vFIPED) if any MNV was present within the FIPED; otherwise, these were graded as avascular FIPED (aFIPED).

RESULTS

217 eyes of 199 patients with chronic CSC and macular FIPED on structural OCT cross-sectional B-scans were included in the study. The mean age was 57.9 ± 13.8 years, and 79.3% were males. 195 (89.9%) eyes had a single FIPED; 20 (9.2%) subjects had 2 FIPEDs, and only 2 (0.9%) eyes had 3 FIPEDs. The overall number of FIPEDs was 243, with a mean number of 1.11 ± 0.34 per eye. Of these, 77% displayed a "compressing" pachyvessel. 64/243 (26.74%) FIPEDs were vascularised. Subjects with vFIPEDs were older than subjects with aFIPEDs (P < 0.001). In the context of a FIPEDs, the presence of "compressing" pachyvessels was more prevalent than in vascularised FIPEDs (68.8 vs. 31.1%; P = 0.380). This prevalence was not influenced by prior treatments (P = 0.414).

CONCLUSION

Our research emphasised a propensity for the presence of pachyvessels that were "compressing" the choriocapillaris beneath the FIPED. However, in the present study, this finding was not associated with vascularised FIPED. Further longitudinal studies would be required to assess the clinical significance of these findings.