Evaluation of choroidal thickness, choroidal vascular diameter, choroidal vascularity index, their correlations, and interocular symmetry in a healthy population.

PURPOSE: This study aims to evaluate the characteristics of choroidal thickness (CT), choroidal vascular diameter (CVD), and choroidal vascularity index (CVI) in a healthy population using swept-source optical coherence tomography (SS-OCT).

METHODS

This cross-sectional study included 148 eyes from 74 healthy adults. SS-OCT was used to evaluate choroid. CT, CVD and CVI were analyzed using standardized imaging and segmentation methods from OCT images. Analyses were performed for interocular symmetry and relationships among CT, CVD, CVI, and demographic factors.

RESULTS

CT exhibited significant thinning from the central to peripheral macular regions. CT values were relatively high, with central thickness exceeding 300 µm in 74.3% of eyes. Age showed a significant negative correlation with CT (r = - 0.325 to r = - 0.477, p < 0.01). Both CT and CVD demonstrated strong interocular symmetry (ICC > 0.86), while CVI showed weak interocular agreement (ICC = 0.34). CVD values were positively correlated with CT (r = 0.661, p < 0.001). CVD values were greater than 300 µm in 18.9% of study eyes. CVI was not different between genders and uncorrelated with age but exhibited a moderate negative correlation with CT (r = - 0.388, p < 0.01). No significant correlation was found between CVI and CVD.

CONCLUSIONS

CT and CVD demonstrated strong interocular symmetry, whereas CVI showed variability between eyes. CT was positively correlated with CVD and negatively correlated with CVI, while no significant correlation was found between CVI and CVD.