Title : Effect of Defocus Incorporated Multiple Segments (DIMS) spectacle lenses on myopia progression in children and adolescents: A 12 month observational study
Abstract:
Background: Myopia prevalence among schoolchildren is rising, and axial elongation (AL) is associated with increased risks of myopic macular degeneration, glaucoma, and retinal detachment. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses induce peripheral myopic defocus and, in clinical trials, slow myopia progression versus single-vision lenses. In routine Russian practice, questions remain regarding tolerance, the influence of baseline myopia severity, and coupling between AL and spherical equivalent refraction (SE).
Objective: To evaluate 12-month changes in AL and SE in children using DIMS lenses under real-world clinical conditions.
Methods: Prospective observational study including 63 children (7–14 years) with myopia −0.50 to −6.00 D. Exclusion: astigmatism >1.5 D, amblyopia, ocular pathology, prior therapy affecting eye growth. Full correction with DIMS lenses was prescribed; wear time ≥12 h/day and ≥90 min/day outdoors were recommended. Measurements: AL (optical biometry) and cycloplegic SE at baseline and 12 months. Statistics: Shapiro–Wilk, paired t-test or Wilcoxon, Pearson correlation (p<0.05). Stratification: mild (n=43) and moderate myopia (n=20).
Results: Overall, AL increased by 0.16 ± 0.06 mm and SE by 0.31 ± 0.08 D (both p<0.001). Mild myopia: AL +0.16 ± 0.06 mm; SE +0.26 ± 0.09 D; moderate ΔAL–ΔSE correlation (r=0.372; p=0.0276). Moderate myopia: AL +0.19 ± 0.17 mm; SE +0.41 ± 0.15 D; no significant correlation (r=0.108; p=0.537). Tolerance was good; discontinuation in 28.6% was due to switching to defocus contact lenses or orthokeratology for greater daytime freedom (e.g., sports). No adverse events requiring cessation were recorded. Findings align with international evidence.
Conclusions: DIMS spectacle lenses provide clinically meaningful slowing of myopia progression over 12 months (AL, SE). AL–SE coupling is evident in mild myopia but attenuates in moderate myopia, supporting stratified, individualized management. DIMS are most advisable in mild myopia, combined with behavioural measures and regular AL/SE monitoring, with transition to combined strategies if needed.
