Fig. 1: Choroidal Vascular Index (CVI) maps captured by SS-OCT in the macular and peripapillary region.

Raw SS-OCT images were taken centered on the macula (A) and optic disc (D). The choroidal vessels were visualized on SS-OCT images and segmented by a deep learning method [29], in the macular region (B) and peripapillary region (E). Choroidal vessels were illustrated in green and choroidal matrix in red. The ETDRS grid was applied to show the CVI of each sector in the macular region (C) and peripapillary region (F). In N, In S, In T, In I corresponded to the inner circle of the ETDRS grid in the nasal, superior, temporal, and inferior sector. Out N, Out S, Out T, Out I referred to the outer circle of the ETDRS grid in the nasal, superior, temporal, and inferior sector. Since the inner and middle circles of the ETDRS grid in the peripapillary region were affected by the optic disc, only the CVI of the outer circle was included in the analysis.