AGE-RELATED CHANGES IN CHOROIDAL VASCULAR DENSITY OF HEALTHY SUBJECTS BASED ON IMAGE BINARIZATION OF SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY

Purpose: To analyze the vascular density of the choroid in a healthy population using swept-source optical coherence tomography. Methods: A cross-sectional, noninterventional study. Inclusion criteria: best-corrected visual acuity between 20/20 and 20/25, spherical equivalent between ±3 diopters, no systemic or ocular diseases, and ages ranging between 3 and 85 years. One hundred and thirty-six eyes from 136 subjects were analyzed, 86 eyes (63.2%) were from male and 50 eyes (36.8%) from female subjects. The eyes were divided into different age groups to analyze the possible age-related changes. Twelve-millimeter horizontal, fovea-centered B-scans were used. Choroidal stroma and vessel area analysis involved automated segmentation and binarization using validated algorithms. Results: Mean age was 33.1 ± 24.5 years. Mean choroidal area was 0.5554 ± 0.1377 mm2. Mean stromal area was 0.2524 ± 0.0762 mm2, and mean vascular region area was 0.3029 ± 0.0893 mm2. The percentage of choroidal vascularity (vascular area/total area) was 54.40 ± 8.35%. Choroid area, vascular region, and percentage of choroidal vascular density were statistically higher in the <18-year-old group versus the >18-year-old group (P < 0.001). The stromal region was not different (P = 0.46). In the same way, choroid area, vascular region, and percentage of choroidal vascular density between the 5 age groups were statistically different (P < 0.001), showing larger figures in the 0 to 10-year-old group, but not stromal region (P = 0.71). There were no gender-related differences. Conclusion: The luminal area and the percentage of vascular/total area decrease with increasing age, while the stromal area remains stable.