Characteristics of retinal and choroidal vessel density in myopic children and changes in myopia progression

To describe the retinal and choroidal vessel density (VD) in myopic children and their changes in myopia progression. One hundred and sixteen children aged 8–15 years with spherical equivalent refractive error (SE) of -0.75 to -5.75 D were enrolled. Superficial and deep retinal VD (SVD and DVD), choroidal and choriocapillaris VD (CVD and CcVD), and choroidal vessel volume (CVV) were measured. In phase two, 60 children followed for one year. SVD was higher than DVD in central region and lower than DVD in parafoveal regions (all p < 0.01). CVD exhibited greater variability in the population and was lower than CcVD in all regions (all p < 0.001). The temporal SVD and DVD correlated negatively with age and axial length (AL) and positively with SE; The central CVD correlated positively with AL; The central CcVD correlated negatively with AL; However, the associations were statistically significant but explained only a small proportion of the variance. During the one-year follow-up, nasal SVD and central DVD increased (both p < 0.01). Nasal CcVD and central CVD increased, but inferior CcVD decreased (all p < 0.01). The vessel density was lower in the superficial retina than in the deep retina, and the choriocapillaris was higher than the whole choroid. With increasing age and myopia, the central and nasal retinal and choroidal vessel density increased.