Optical coherence tomography angiography in pediatric myopia: effects of myopia severity on retinal and choroidal thickness and microvascular perfusion

• Myopia has now emerged as a major global public health concern, with its prevalence continuing to rise and the age of onset shifting progressively toward younger populations, which substantially increases the risk of individuals developing high myopia and related blinding retinal lesions. • OCTA can non-invasively, rapidly, and with high resolution display the morphology and blood perfusion of retinal and choroidal vessels, offering a powerful tool for investigating the pathophysiological mechanisms of some ocular diseases in children. • Peripapillary radial capillary (RPC) density is significantly reduced in highly myopic children and closely associated with retinal nerve fiber layer thinning, especially in the superior, inferior, and nasal sectors. • The UWF SS-OCTA not only enables precise characterization of vortex vein (VV) system morphology in myopic eyes but also links localized reductions in choroidal perfusion with hemodynamic alterations in retrobulbar feeding arteries. Such evidence provides direct imaging-based support for the critical role of choroidal ischemia in myopia-related posterior scleral expansion and thick-choroid–related disorders To summarize current applications of optical coherence tomography angiography (OCTA) in pediatric myopia, focusing on myopia severity–related changes in retinal and choroidal microvasculature. A narrative review of published OCTA studies in myopic children and adolescents was performed, emphasizing macular, peripapillary, and choroidal vascular alterations and recent technological advances. Evidence suggests that the foveal avascular zone (FAZ) is largely preserved in mild to moderate pediatric myopia, whereas area reduction or morphological changes are mainly observed in high myopia, with axial length (AL) as the primary determinant. Superficial capillary plexus (SCP) vessel density generally decreases with AL elongation, particularly in parafoveal regions, although relative preservation or compensatory regulation may occur centrally. The deep capillary plexus (DCP) shows the highest sensitivity to axial elongation, with pronounced vessel density reduction in parafoveal and perifoveal areas, indicating early microcirculatory impairment. Peripapillary radial capillary (RPC) density is significantly reduced in highly myopic children and closely associated with retinal nerve fiber layer thinning, especially in the superior, inferior, and nasal sectors. Choroidal thickness is consistently negatively correlated with AL, while findings on choroidal perfusion remain variable, suggesting potential compensatory mechanisms in childhood. Advances in ultra-widefield swept-source OCTA and artificial intelligence have improved imaging coverage and analytical consistency. OCTA enables detailed, layer-specific assessment of microvascular alterations in pediatric myopia, with the DCP and peripapillary circulation serving as sensitive indicators of early disease-related changes. When combined with choroidal thickness or the choroidal vascularity index, this approach helps enhance the individualized prediction of myopia progression risk and the accuracy of intervention efficacy evaluation. Meanwhile, well-designed longitudinal studies with standardized pediatric protocols are required to establish normative parameters and support early monitoring and intervention.