MiYOSMART (DIMS) spectacle lenses: what the clinical trial evidence shows

MiYOSMART (Hoya), often searched for as MyoSmart, is a spectacle lens for slowing myopia in children. It uses Defocus Incorporated Multiple Segments (DIMS) technology developed with The Hong Kong Polytechnic University. This review sets out what the published trials show.

How DIMS lenses work

A clear central zone corrects distance vision. Around it sits a honeycomb of small segments, each adding +3.50 D of myopic defocus. The child sees clearly through the gaps between segments while the segments place a second image in front of the retina.

What the evidence shows

Two years. In a double-masked randomised trial, 183 Chinese children aged 8 to 13 were assigned to DIMS or single-vision spectacles and 160 completed two years. Myopia progressed by 0.41 D with DIMS against 0.85 D with single vision, 52% slower. Axial length grew 0.21 mm against 0.55 mm, 62% less. 21.5% of DIMS wearers had no progression over two years, against 7.4% of single-vision wearers (Lam et al., 2020).

Six years. Children who wore DIMS for six years showed no significant difference in progression between the first and the later three years, so the effect was sustained. Groups who stopped DIMS wear showed no evidence of rebound, and visual function after wear was within normal limits (Lam et al., 2023).

An honest read of the evidence

• The pivotal trial was run at one centre in Hong Kong Chinese children, and three authors were employees of the manufacturer.
• The six-year groups were small (36 children wore DIMS throughout) and no longer randomised, so the long-term findings are supportive rather than conclusive.
• Later analyses suggest the effect varies with a child's baseline peripheral refraction, so not every child responds equally.

Myopia device research at NZERC

Spectacle-based myopia control still lacks head-to-head trials between lens designs and good data outside East Asian populations. The New Zealand Eye Research Centre (NZERC) measures axial length and choroidal thickness and vascularity and is set up to contribute that data. Lens manufacturers and sponsors are invited to read our information for sponsors and CROs. Families can register their interest in myopia studies. For assessment and treatment, contact our affiliated clinical practice, Rose Optometry.

References

• Lam CSY, Tang WC, Tse DY, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol 2020;104(3):363-368. doi:10.1136/bjophthalmol-2018-313739
• Lam CSY, et al. Long-term myopia control effect and safety in children wearing DIMS spectacle lenses for 6 years. Sci Rep 2023;13(1):5475. doi:10.1038/s41598-023-32700-7
• Zhang H, et al. Myopia control effect is influenced by baseline relative peripheral refraction in children wearing DIMS spectacle lenses. J Clin Med 2022. doi:10.3390/jcm11092294