Effects of Different Refractive Status on Retinal and Choroidal Thickness and Blood Flow in Children Assessed by Optical Coherence Tomography Angiography.

PURPOSE: To investigate the changes in microcirculation and structural characteristics of the retina and choroid in children with different refractive statuses using swept-source optical coherence tomography angiography (SS‑OCTA). METHODS: A total of 161 eyes from 105 healthy children aged 5-18 years were enrolled and divided into seven groups according to spherical equivalent (SE), ranging from high myopia to high hyperopia. A 6 × 6 mm macular SS‑OCTA scan was performed to measure the foveal avascular zone (FAZ), superficial and deep retinal vessel densities and vessel length densities, choroidal capillary and choroidal flow areas, choroidal vascularity index (CVI), retinal thickness (RT), and choroidal thickness (CT). Generalized estimating equations (GEE) were used to analyze the effects of SE and axial length (AL). RESULTS: Significant differences were found among groups in FAZ, retinal vessel density, RT, choroidal flow area, CVI, and CT. The high hyperopia group exhibited enlarged FAZ, reduced foveal superficial and deep vessel densities and vessel length densities, and thinner foveal retina; the high myopia group showed decreased perifoveal vessel density and vessel length densities, thinner retina and choroid, along with increased choroidal flow area and CVI. No significant intergroup differences were observed in choriocapillaris flow area. GEE analysis revealed that both SE and AL were independent influencing factors for multiple OCTA parameters, with CT and CVI showing the strongest associations with refractive status. CONCLUSION: Refractive changes in children are accompanied by selective remodeling of macular blood flow and structure, with differential alterations between the foveal and peripheral regions. SS‑OCTA can effectively detect fundus microstructural and flow changes related to refractive development in children, and SVP‑VD, RT, CT, and CVI are potential monitoring indicators.