Myopia Control Efficacy of Spectacle Lenses with Aspherical Lenslets: Results of a 3-year Follow-up Study

& BULL; PURPOSE: To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with slightly aspherical lenslets (SAL) and single-vision spectacle lenses (SVL) to HAL for 1 year after a 2-year myopia control trial. & BULL; DESIGN: This was a 1-year extension of a randomized clinical trial. & BULL; METHODS: Of 54 children who had worn HAL for 2 years, 52 continued wearing HAL (HAL1 group), and of the 53 and 51 children who had originally worn SAL or SVL, 51 and 48 switched to wearing HAL (HAL2 and HAL3 groups) in year 3, respectively. A new SVL (nSVL) group of 56 children was recruited, matched for age, sex, cycloplegic spherical equivalent refraction (SER), and axial length (AL) of the HAL3 group at extension baseline, and used for a comparison of third-year changes. SER and AL were measured every 6 months in year 3. & BULL; RESULTS: During year 3, the mean (SE) myopia progression in the nSVL group was -0.56 (0.05) diopters (D). Compared with nSVL, the changes in SER were less in HAL1 ( -0.38 [0.05] D, P = .02), HAL2 ( -0.36 [0.06] D, P = .01), and HAL3 ( -0.33 [0.06] D, P = .005). The mean (SE) AL elongation in the nSVL group was 0.28 (0.02) mm. Compared with nSVL, the elongation in AL was less in the HAL1 (0.17 [0.02] and HAL3 (0.14 [0.02] mm, P < .001) groups. Myopia progression and axial elongation were comparable in all 3 HAL groups (all P > .05) in year 3. & BULL; CONCLUSIONS: Myopia control efficacy has r mained in children who wore HAL in the prev ous 2 years. Children who switched from SAL or SVL to HAL in year 3 had slower myopia pr gression and axial elongation than that in the co trol group