This randomized clinical trial aimed to evaluate whether spectacle lenses with aspherical lenslets slow myopia progression over 2 years and whether the level of lenslet asphericity affects myopia control efficacy in a dose-dependent manner.

ObjectiveSpectacle lenses with highly aspherical lenslets (HAL) and slightly aspherical lenslets (SAL) showed effective myopia control. This study was to investigate their effects on macular choroidal thickness (ChT) in myopic children.MethodsExploratory analysis from a 2-year, double-masked, randomised trial. 170 children aged 8–13 years with myopia between −0.75D and −4.75D, astigmatism of 1.50D or less, and anisometropia of 1.00D or less were recruited. Participants were randomly assigned in a 1:1:1 ratio to receive HAL, SAL or single vision spectacle lenses (SVL). The subfoveal, parafoveal and perifoveal ChT were evaluated every 6 months.Results154 participants completed all examinations. The ChT showed significant changes over time in all three groups in all regions (all p<0.05). The ChTs continuously decreased in the SVL group (ranging from −20.75 (SD 22.34) μm to −12.18 (22.57) μm after 2 years in different regions). Compared with the SVL group, ChT in the SAL group decreased less (ranging from −16.49 (21.27) μm to −5.29 (18.15) μm). In the HAL group, ChT increased in the first year and then decreased in the second year (ranging from −0.30 (27.54) μm to 8.92 (23.97) μm after two years). The perifoveal ChT decreased less than the parafoveal ChT, and the superior region decreased the least.ConclusionsThe ChT of the macula decreased after 2 years of myopia progression with SVL. Wearing spectacle lenses with aspherical lenslets reduced or abolished the ChT thinning and HAL had a more pronounced effect.Trial registration numberChiCTR1800017683.