Wide-field Choroidal Vascularity in Healthy Eyes

Purpose: To report variation of choroidal vascularity index (CVI) in macular and mid-equator areas in healthy subjects using wide-field optical coherence tomography (WF-OCT). Design: Prospective, cross-sectional study. Methods: SETTING: Two-center study. STUDY POPULATION: Twenty eyes of 20 healthy subjects. OBSERVATION PROCEDURE: Single high-definition scans passing through the fovea in both vertical and horizontal meridians were studied. Images were taken in primary gaze and extremes of gaze and a manual montage was created. A previously reported semi-automated algorithm was used to calculate the CVI in macular, superior, inferior, temporal, and nasal quadrants. MAIN OUTCOME MEASURES: Difference in CVI in macular area and 4 quadrants. Results: Twenty eyes from 20 subjects were enrolled in the study. The mean age was 28.85 ± 6.29 years with men comprising 9 of the 20 subjects (45.0%). The refractive error (spherical equivalent) ranged from −3.00 to +0.75 diopters. The average CVI in the macular area (40.01 ± 7.67) was significantly smaller than in any of the other fundus areas (all P <.01). The maximum CVI was seen in the nasal quadrant (50.84 ± 5.64), followed by inferior (47.93 ± 9.31), temporal (46.14 ± 7.06), and superior (45.72 ± 7.69). The nasal quadrant was found to have the least coefficient of variation (CV) of CVI (0.11) while the inferior and macular area had the highest CV (0.19). Conclusions: We report CVI in WF-OCT in healthy young individuals. CVI seems to have a wide topographic variation. The macular area had the least CVI. CVI values are more consistent with lesser CV in the nasal quadrant compared to the other quadrants and macular area.