Compartmental analysis of three-dimensional choroidal vascularity and thickness of myopic eyes in young adults using SS-OCTA

Abstract

Purpose: We aimed to investigate the change of three-dimensional (3D) choroidal thickness (ChT), choroidal vessel volume (CVV), and choroidal vessel index (CVI) in young myopic adults using swept-source optical coherence tomography angiography (SS-OCTA) and compare the difference of these indicators in different quadrants of the macula and optic disc.Methods: A total of 248 eye samples from 135 participants were used in this cross-sectional study. Each participant underwent detailed history taking and ocular examinations. Based on axial length (AL), patients were divided into the emmetropia (EM) group, mild-myopia (MIM) group, moderate-myopia (MOM) group, and high-myopia (HM) group. 6 mm × 6 mm (1,024 × 1024 B-scans) SS-OCTA scans were performed centered on the fovea and optic disc. 3D ChT, CVV, and CVI were measured based on a built-in deep learning algorithm. Differences in ChT, CVV, and CVI were analyzed in different regions and different myopic groups.Results: Significant reduction in the global CVV were found in the HM group (1.930 ± 0.865) in comparison with the EM (3.486 ± 0.992), MIM (3.238 ± 1.033), and MOM (2.589 ± 1.083) groups (p < 0.001). The global CVI was also lower in the HM group (0.258 ± 0.061) than in the EM (0.320 ± 0.055), MIM (0.320 ± 0.051), and MOM (0.286 ± 0.066) groups (p < 0.001). The ChT was thinner in eyes with HM (242.753 ± 65.641) than in eyes with EM (377.532 ± 80.593), MIM (348.367 ± 78.191), or MOM (300.197 ± 87.175) (p < 0.001). Compartmental analysis revealed that ChT, CVV, and CVI in the nasal quadrant of the macula and temporal and inferior quadrants of the optic disc were much lower than those in other quadrants (p < 0.05). Correlation analyses found that ChT, CVV, and CVI were negatively correlated with AL and spherical equivalence.Conclusion: 3D ChT, CVV, and CVI gradually decreased as the degree of myopia increased. The changes were more dramatic on the nasal side of the macula and the temporal and inferior sides of the optic disc. These findings demonstrated the 3D choroidal change and highlighted the papillo-macular bundle as a sensitive region in myopic development.

Change in three‐dimensional choroidal vessel network after AR device assisted 1‐hour visual task in 2D/3D mode in young healthy subjects

“…Images with poor scan quality (less than 7/10 signal strength index), motion artefact, segmentation artefact or focal signal loss were excluded. The VG200's van Gogh software uses artificial intelligence algorithms (Chen et al, 2022; Luo et al, 2022) to identify the contours of the large and medium choroidal vessels in the B‐scans and then forms the morphology of vessels through three‐dimensional reconstruction to realize quantification of the large and medium choroidal vessels. It is a three‐dimensional index that reflects the volumetric choroidal vascularity density.…”

Assessment of the effects of myopic and hyperopic anisometropia on choroidal vascular structure in children using SS‐OCTA

“…The choroidal lumen area in each B-scan was identified automatically by a deep learning algorithm, as performed in previous studies (Figure 3) and the superior and inferior boundaries of the choroid were also identified automatically (Figure 3). [22][23][24] Additionally, three-dimensional reconstruction was performed to calculate the choroidal lumen volume (3D-CVV) and total choroidal volume (TCV). The three-dimensional choroidal vascular index (3D-CVI) was defined as the ratio of the choroidal luminal volume (LV) to the TCV, which was also calculated automatically by the built-in software.…”

Validation of reliability, repeatability and consistency of Three-dimensional Choroidal Vascular Index

“…However, most CVI was obtained studies are quantitative research on the two-dimensional choroidal vascular index, which is based on the calculation of a single optical coherence tomography (OCT) B-scan obtained through the fovea or a selected location. However, due to the topographical changes of the choroid, this index cannot fully represent the changes in the choroidal vascular structure [13]. Therefore, the threedimensional or volumetric information of the choroid should be used to accurately evaluate choroidal vessels, such as the three-dimensional choroidal vessel index (3D-CVI) [14].…”