*Article* **En Face Choroidal Vascularity in Both Eyes of Patients with Unilateral Central Serous Chorioretinopathy**

**Filippo Tatti 1, Claudio Iovino 1,2, Giuseppe Demarinis 1, Emanuele Siotto Pintor 1, Marco Pellegrini 3, Oliver Beale 4, Kiran Kumar Vupparaboina 4, Mohammed Abdul Rasheed 5, Giuseppe Giannaccare 3,6, Jay Chhablani <sup>4</sup> and Enrico Peiretti 1,\***


**Abstract:** The aim of this study was to evaluate the choroidal vascularity analyzing en face optical coherence tomography (OCT) images in patients with unilateral central serous chorioretinopathy (CSC). We retrospectively evaluated 40 eyes of 20 CSC patients and 20 eyes of 10 gender- and agematched healthy individuals. The sample consisted of: (1) CSC affected eyes; (2) unaffected fellow eyes; (3) healthy eyes. Multiple cross-sectional enhanced depth imaging OCT scans were obtained to create a volume scan. En face scans of the whole choroid were obtained at 5μm intervals and were binarized to calculate the choroidal vascularity index (CVI). The latter, defined as the proportion of the luminal area to the total choroidal area, was calculated at the level of choriocapillaris, superficial, medium and deep layers. No significant differences between choriocapillaris, superficial, medium and deep CVI were found in both eyes of CSC patients, whereas a significant different trend of changes was found in healthy eyes. Nevertheless, the en face CVI shows no difference between affected fellow and healthy eyes. In conclusion, CSC-affected eyes and fellow eyes showed a similar vascular architecture, with no statistical difference between all choroidal layers.

**Keywords:** central serous chorioretinopathy; pachychoroid; en face optical coherence tomography; choroid; choroidal vascularity index
