Aims To evaluate the variable depth tomographic features of choroidal vasculature in acute and chronic central serous chorioretinopathy (CSC) using swept source optical coherence tomography (SS-OCT) en face imaging.

Methods We retrospectively reviewed the en face SS-OCT images of 29 patients that presented with acute (12 eyes) or chronic (17 eyes) CSC. All of the patient eyes underwent 6×6 macular scans with SS-OCT (DRI OCT-1, Topcon, Tokyo, Japan), fluorescein angiography and indocyanine green angiography. The en face image was used to investigate the choroidal vasculature of each layer. Moreover, we determined that some parts corresponded to choriocapillaris and Sattler's layer attenuation, whereas choroidal vessel dilatation was associated with Haller's layer.

Results At Haller's layer level, choroidal vessel dilatation was observed in 11 of 12 acute CSC (91.7%) and 15 of 17 chronic CSC (88.2%). In acute CSC, choroidal vessel dilatation was divided into focal (9/11; 81.8%) and diffuse (2/11; 18.2%) patterns. The chronic CSC cases demonstrated different patterns of choroidal vessel dilatation: focal (5/15; 33.3%) and diffuse (10/15; 66.6%). Ten of the acute CSC eyes (83.3%) and 14 of the chronic CSC eyes (82.4%) were found to have obscured choriocapillaris and Sattler's layers on en face imaging.

Conclusions En face imaging of SS-OCT is useful when combined with angiography in CSC for evaluating choroidal vessel dilatation at Haller's layer and to identify obscured upper layers. We identified different choroidal vessel dilatation patterns between acute and chronic CSC. These findings might be useful for pathophysiological understanding of CSC.