Features of the Choroidal Structures in Myopic Children Based on Image Binarization of Optical Coherence Tomography

Abstract

To evaluate the features of the choroidal structures in the eyes of myopic children obtained by enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS. Ninety-six myopic children with low to moderate myopia (spherical equivalent refractive error [SER],-5.75 to-1.00 diopter) were included in this cross-sectional study. Ocular biometrics were measured using an optical low-coherence reflectometry device. Data of the choroidal structures extracted from a 7500-μm cross-sectional arc of the choroid extending from the temporal optic disc margin, including the total choroidal area, luminal area, stromal area, and choroidal vascularity index, were determined by image binarization of the EDI-OCT. Associations between demographic factors, ocular parameters, and choroidal structures were evaluated using univariate and multiple linear regression analyses. RESULTS. The study participants (mean age, 11.02 ± 1.70 years) had a mean axial length (AL) of 24.94 ± 0.70 mm. The mean total choroidal area was 2.64 ± 0.49 mm 2 (luminal area, 1.68 ± 0.32 mm 2 ; stromal area, 0.95 ± 0.19 mm 2), and the choroidal vascularity index was 0.64 ± 0.03. Multiple regression analysis showed that the luminal area was significantly associated with the AL (standard β =-0.24, P = 0.022) after adjusting for sex and corneal radius (CR), whereas the stromal area (standard β =-0.30, P = 0.003) and choroidal vascularity index (standard β = 0.36, P = 0.001) were significantly associated with age after adjusting for sex, CR, and lens thickness (LT). Sex, CR, LT, and SER showed no significant association with choroidal structures after adjusting for age and AL (all P > 0.05). CONCLUSIONS. The luminal area of the choroid tends to decrease with a longer AL, whereas the stromal area tends to decrease with increasing age in myopic children. These findings require further exploration in a longitudinal study.

Assessment of Choroidal Vascularity and Choriocapillaris Blood Perfusion in Anisomyopic Adults by SS-OCT/OCTA

“…The former reflects the circulatory volume in Haller's and Sattler's layers, and the latter reflect areas in the choriocapillaris with low perfusion or without perfusion, thus outlining the global choroidal circulation. These methods have shown good repeatability and reproducibility in studies by others, 32 , 33 , 42 , 44 , 45 as well as by us in the present work.…”

Choroidal Biomarkers: A Repeatability and Topographical Comparison of Choroidal Thickness and Choroidal Vascularity Index in Healthy Eyes

“…Interestingly, this eccentricity-dependent correlation pattern is the inverse of the ChT and CVI correlation described above. Previous correlation findings appear somewhat inconclusive; low negative correlations of CVI with AEL have been reported, 12 , 18 , 47 while slightly increased vascular components with myopia have also been observed. 20 , 21 However, these findings are all limited to the central or maximally the outer scan fields and do not all reach statistical significance.…”

“…This is consistent with earlier studies, although these found generally lower absolute CVI values of around 45% to 65%. 12 , 18 , 47 , 48 These differences likely arise from the use of different OCT devices, scan patterns, image-processing algorithms, and participant age and ethnicity distributions. However, it has been stated that central CVI (measured in two dimensions) is not significantly influenced by the choice of scan pattern 49 or OCT device.…”

“… 17 While there are only a few studies existent, they report only vague and somewhat inconsistent association between choroidal vascularity and myopia. 18 – 21 …”

Effects of Atropine Treatment on Choroidal Thickness in Myopic Children

“…Similar results were found in myopic children treated with orthokeratology. 26,27 These findings suggest that the choroidal thickening may participate in ocular growth retardation, probably by influencing the synthesis activity of molecular signals and the transmission ability of choroid, [19][20][21][22] or by increasing the ChT and choroidal blood flow [44][45][46] and mitigating scleral hypoxia. 18 We found that the ChT change at the 1-week visit was negatively associated with the IAL change over 6 months in group A, which suggests that the short-term increase in ChT after a loading dose of 1% atropine may predict longterm eye elongation with weekly treatment.…”