DIMS plus atropine vs ortho-k for myopia control

Paper title: Effectiveness of DIMS combined with atropine and orthokeratology in a real-world setting in China

Authors: Song D (1), Chen Y (1), Yao J (1), Chen J (2)

1 Department of Ophthalmology, Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
 2 Department of Ophthalmology, Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.

Date: Published online July 5, 2025

Reference: Song D, Chen Y, Yao J, Chen J. Effectiveness of DIMS combined with atropine and orthokeratology in a real-world setting in China. Cont Lens Anterior Eye. 2025 Dec;48(6):102473.

[Link to abstract]

Orthokeratology and defocus incorporated multiple segments (DIMS) spectacle lenses (Hoya MiYOSMART) are widely used optical treatments for slowing myopia progression in children. Previous studies have compared orthokeratology and DIMS spectacle lenses for myopia control with some reports suggesting similar or greater efficacy with orthokeratology. More recently, combining DIMS lenses with low-concentration atropine (0.01%) has emerged as a potential strategy to enhance treatment efficacy.

However, there is limited evidence directly comparing DIMS combined with atropine against orthokeratology, particularly in real-world clinical settings where treatment choices are based on patient preference rather than randomized allocation. This study therefore aimed to compare these two approaches in children with mild to moderate myopia.

In this non-randomized clinical study, 161 children aged 6–15 years, with myopia between -0.75 and -6.00D, were analyzed following treatment at a hospital in China. Participants were allocated according to patient and guardian preference to either DIMS lenses combined with 0.01% atropine (n=88) or orthokeratology (n=73), with outcomes assessed over 12 months.

Key points were as follows.

• After one-year, axial elongation was 0.14 ± 0.18 mm in the DIMS+atropine group and 0.20 ± 0.18 mm in the orthokeratology group.
• 55.7% of children in the DIMS+atropine group showed axial elongation ≤0.15 mm, compared with 42.5% in the orthokeratology group.
• Axial length stability or potential shortening (magnitude not defined by the authors) was observed in 23.9% of DIMS+atropine patients and 8.2% of orthokeratology patients after 12 months.
• Baseline age was the main factor influencing axial elongation, with younger children experiencing greater axial elongation in both groups.
• The DIMS+atropine group reported no notable adverse events, while mild corneal staining occurred in 15.1% of orthokeratology patients during follow-up.

This study provides real-world evidence comparing DIMS spectacle lenses combined with 0.01% atropine to monotherapy orthokeratology, finding a marginal difference in axial elongation (0.06mm) between treatments over one year. 

This approach may be relevant for patients who are not suitable candidates for overnight contact lens wear or where families prefer a spectacle-based intervention.

An additional observation in the study was that some children showed “negative axial length growth,” meaning axial length measurements that were shorter than baseline at follow-up. The magnitude was not defined in the paper – some percentage of these could be an indication of axial length stability, if measurements were within the repeatability of the biometry (eg. +/-0.05mm), and not a true ‘shortening’ of axial length. For practitioners monitoring axial length in clinical practice, this highlights that  small reductions in axial length may occasionally occur, but should be interpreted cautiously, as they could be attributed to measurement variability or short-term ocular structural changes such as choroidal thickening, rather than true reversal of eye growth.

Taken together, these findings suggest that combining optical and pharmacological interventions may provide an effective alternative to orthokeratology for some patients, while reinforcing the importance of selecting myopia control strategies based on individual patient characteristics and treatment preferences.

While this study provides real-world insight into how two commonly used myopia control approaches compare, several questions remain. The study used a non-randomized design in which treatment allocation was based on patient and guardian preference, reflecting routine clinical practice. However, younger children were less likely to be fitted with orthokeratology lenses, as local protocols in China typically recommend orthokeratology from around 8 years of age.

Baseline age differed between the groups, with children in the orthokeratology group being older on average. Baseline age was identified as the main factor influencing axial elongation, with older children showing slower eye growth in both treatment groups. Although statistical adjustment was applied, this age difference may still have influenced the comparison between treatments.

Interpretation of refractive outcomes is also limited, as spherical equivalent refraction was not measured during follow-up in the orthokeratology group due to corneal reshaping effects. As a result, associations between baseline age and refractive progression could only be assessed in the DIMS+atropine group.

Measuring axial length at baseline and monitoring changes over time is important for the most accurate measure of myopia progression and treatment efficacy, but caution should be applied in suggesting a treatment is ‘reversing’ axial length growth. Moreover, with a one year limited follow up, these effects may not be long-lasting. Finally, this study did not directly compare the effect of DIMS vs ortho-k as monotherapies – the question of how they would compare when both used in combination with atropine 0.01% is yet to be answered. 

Background and objectives: Myopia cases have markedly increased worldwide, particularly in younger individuals. This study evaluates the effect of defocus incorporated multiple segments (DIMS) lens combined with atropine (DIMSA) in the control of myopia progression versus orthokeratology (ortho-k) lenses.

Methods: In this non-randomized controlled clinical study, 180 eyes in 180 myopic children treated at the Nanjing Children's Hospital between January 2022 and February 2023 were included. According to the preferences of patients and their guardians, the participants were divided into the DIMSA and ortho-k groups, with 90 cases (90 eyes) each. Totally 161 patients in both groups met the inclusion and exclusion criteria, including 88 and 73 in the DIMSA and ortho-k groups, respectively. Right eye parameters were analyzed. Both groups were compared in terms of change in axial length (AL), AL negative growth rate and AL elongation rate after a one-year visit.

Results: No significant differences were found in baseline features other than age between the DIMSA and ortho-k groups. After a one-year treatment, no statistically significant difference was found in axial elongation (AE) between the two groups. After adjustment for baseline age, axial elongations in the DIMSA and ortho-k groups were 0.14 ± 0.18 mm and 0.20 ± 0.18 mm (P = 0.025), respectively. Baseline age was the only factor impacting the axial control efficacy of DIMSA and ortho-k lenses, with a negative association between AE and age in both groups and a positive association between spherical equivalent refraction (SER) increase and baseline age in the DIMSA group. The DIMSA group exhibited higher AL negative growth and AL slow growth (≤0.15 mm) rates after one year compared with the ortho-k lens group (P = 0.008 and P = 0.004, respectively).

Conclusions: DIMSA demonstrated marginally superior myopia control efficacy compared to ortho-k lenses in children with mild to moderate myopia in a real-world setting in China.

[Link to abstract]