Choroidal Features of Healthy Iranian Individuals

To assess subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) profile in the Iranian healthy population and assessment of the inter-eye difference in this regard.

In a cross-sectional study, 141 healthy subjects underwent an assessment of refraction and best-corrected visual acuity (BCVA), axial length (AL), and measurement of the intraocular pressure. The imaging of the choroid was performed using the enhanced-depth imaging mode of Spectralis optical coherence tomography from the foveal slab to measure SFCT and calculate CVI.

A total of 282 eyes of 141 healthy subjects (59.6% men, mean age of 60.86 ± 11.46 years) enrolled in the current study. The mean SFCT of the right and left eye was 247.40 ± 70.37 and 251.25 ± 72.19, respectively. The mean CVI of the right and left eye was 62.63 ± 3.77 and 63.19 ± 3.91, respectively. None of the measured parameters had statistically significant differences between the left and right eyes. In both univariate and multivariate regression analysis, CVI was significantly associated with BCVA (P < 0.001) but was not associated with age, spherical equivalent (SE), gender, central macular thickness (CMT), and SFCT. In univariate regression analysis, SFCT was significantly associated with age, refraction (P = 0.02), BCVA (P = 0.003), AL (P < 0.001), and CVI (P = 0.02) but not significantly associated with gender and CMT. In multivariate analysis, age (P < 0.001), gender (P = 0.001), and AL (P < 0.001) were significantly associated with SFCT, but SE, BCVA, CVI, and CMT were not significantly associated.

This was the first investigation to assess the SFCT and CVI simultaneously in the Iranian population to establish a normative database for future studies. CVI was less variable than SFCT in a healthy population, and no statistically significant differences existed between the left and right eyes.