Defocus Lens Design Slows Myopia Progression in Spanish Children Over 18 Months

An 18-month prospective observational study of 45 Spanish children aged 9 to 14 years found that spectacle lenses incorporating defocus segments were associated with slower myopia progression than conventional single-vision lenses, without measurable costs to visual quality or binocular function.

The non-randomized comparative study allocated participants to three types of optical correction: single-vision lenses, low-addition progressive addition lenses, or defocus-incorporated multiple segments (DIMS) lenses. Researchers tracked refractive error as spherical equivalent and measured axial length, along with a broad battery of accommodative and binocular vision tests, at baseline and at 6, 12, and 18 months.

After 18 months, mean spherical equivalent progression was −0.59 diopters in the single-vision group, −0.51 diopters with progressive addition lenses, and −0.30 diopters with DIMS lenses, corresponding to a 49% reduction in progression with DIMS compared with single-vision correction. Axial length increased by 0.24, 0.27, and 0.23 millimeters in the three groups respectively, although these inter-group differences were not statistically significant.

Beyond refractive outcomes, the study assessed accommodative function through amplitude of accommodation, positive and negative relative accommodation, accommodative facility, and accommodative response, while binocular function was evaluated with phorias, fusional vergences, and stereopsis. Contrast sensitivity, a visual disturbance index, and subjective visual quality were also monitored throughout the follow-up period.

Accommodative and binocular functions, visual acuity, contrast sensitivity, and the visual disturbance index remained stable across the study, and distance stereopsis improved in the DIMS group. The authors conclude that the findings suggest an association between DIMS lens wear and reduced myopia progression compared with single-vision lenses in this cohort, without clinically relevant differences in accommodative or binocular function, visual acuity, or subjective visual quality.

Subject of Research: Comparative effects of DIMS, progressive addition, and single-vision lenses on myopia progression and visual function in children

Article Title: Comparative longitudinal evaluation of DIMS, progressive addition and single-vision lenses on myopia progression, binocular and visual performance in Spanish children

Article References: Solano-Molina, S., Carrillo-Pulido, M., Ortiz-Peregrina, S., Martino, F., Anera, R. G., & Jiménez, J. R. (2026). Comparative longitudinal evaluation of DIMS, progressive addition and single-vision lenses on myopia progression, binocular and visual performance in Spanish children. PLOS One, 21(10), e0361471. https://doi.org/10.1371/journal.pone.0361471

Image Credits: AI Generated

DOI: 10.1371/journal.pone.0361471

Keywords: myopia, DIMS lenses, spectacle lenses, axial length, children, binocular vision, accommodation, contrast sensitivity, progressive addition lenses, refractive error, Comparative, longitudinal