Defocus Incorporated Multiple Segments (DIMS) spectacle lenses in UK children: Outcomes from a 2-year multi-site...

Myopia is a growing public health concern with long-term risks for visual impairment. While Defocus Incorporated Multiple Segments (DIMS) spectacle lenses have proven efficacy in Chinese children, evidence from Western populations remains limited. This multi-site interventional study evaluates the effectiveness of DIMS lenses in slowing myopia progression and their visual acceptability and tolerability among UK children.

Children aged 5-15 years with cycloplegic spherical equivalent refraction (SER) of -0.50 to -8.50 D, anisometropia ≤1.50 D and astigmatism ≤2.50 D were recruited. All participants were prescribed DIMS spectacle lenses. SER (cycloplegic autorefraction) and axial length (AL, IOLMaster) were measured at baseline and at 6-monthly intervals for 24 months. Measured axial elongation was compared to expected eye growth in age- and ethnicity-matched untreated myopes from published meta-analyses. Visual function (distance/near visual acuity, stereoacuity, accommodative lag and ocular posture) and visual symptoms (participant questionnaire) were also assessed.

A total of 108 participants completed the study to 2 years (baseline age 10.2 ± 2.2 years). Model-adjusted mean (SE) changes in SER and AL change were -0.35 ± 0.04 D and 0.17 ± 0.01 mm at 12 months and -0.57 ± 0.05 D and 0.30 ± 0.03 mm at 24 months. Compared to expected untreated myopic progression, children wearing DIMS spectacle lenses showed 0.27 ± 0.20 mm (mean ± SD) less axial elongation over 24 months, with 91% exhibiting slower than average untreated myopic eye growth. Measures of visual function were comparable through DIMS and single-vision spectacle lenses. Fifty-seven percent of participants reported no visual symptoms within the first week, and on average, visual symptoms were 'never' or 'seldom' experienced by participants after 12 and 24 months of DIMS wear.

This study provides robust and novel evidence demonstrating that DIMS spectacle lenses provide meaningful slowing of axial elongation among UK children. Minimal visual symptoms and preserved visual function throughout lens wear support their clinical viability and real-world applicability for myopia management in diverse populations.