Eleven-year outcomes of orthokeratology for myopia

Paper title: Eleven years of orthokeratology contact lens wear for slowing myopia progression in children

Authors: Santodomingo-Rubido J (1), Villa-Collar C (2,3), Gutiérrez-Ortega R (2), Sugimoto K (1), Nishimura S (1), Newman S (1)

1. Menicon Co., Ltd, Nagoya, Japan
2. Clínica Oftalmológica Novovision, Madrid, Spain
3. Faculty of Health Sciences, Universidad Europea de Madrid, Madrid, Spain

Date: April 2025

References: Santodomingo-Rubido J, Villa-Collar C, Gutiérrez-Ortega R, Sugimoto K, Nishimura S, Newman S. Eleven years of orthokeratology contact lens wear for slowing myopia progression in children. Optom Vis Sci. 2025 May 1;102(5):346-352

[Link to open access paper]

Orthokeratology is an established myopia control intervention with substantial evidence supporting its ability to slow axial elongation in children. However, most studies have evaluated treatment effects over relatively short periods, leaving uncertainty regarding long-term effectiveness. This prospective, non-randomised study followed White European children (in Spain) aged 6–12 years with myopia of −0.75D to −4.00D who wore either orthokeratology lenses or single vision correction, comparing axial elongation between groups over an 11-year period. Axial length was measured at 6-month intervals during the initial 2-year study period, with additional follow-up assessments conducted at approximately 7 and 11 years after baseline. While 61 participants started the study, 26 attended the 11-year visit.

Key points were as follows.

• Compared with single vision correction, orthokeratology reduced axial elongation by 0.22mm after 2 years, 0.45mm after 7 years and 0.69mm after 11 years
• At 11 years, cumulative axial elongation was 1.11 mm in the orthokeratology group and 1.80 mm in the control group. 
• Younger baseline age was associated with greater axial elongation in the control group, but not in the orthokeratology group. 
• Children with steeper corneas at baseline showed less axial elongation with orthokeratology, suggesting that corneal shape may influence treatment efficacy.

This study extends our understanding of the long-term outcomes of orthokeratology for myopia management. Compared with single vision correction, children in the orthokeratology group showed 0.69 mm less axial elongation after 11 years, with the difference between groups increasing throughout the follow-up period. While much of the treatment effect occurred during the first few years of wear, the findings suggest that the cumulative difference in axial elongation between orthokeratology and single vision correction may continue to increase over longer periods of treatment.

These findings may be useful when discussing treatment expectations with parents. The greatest treatment effect was observed during the initial years of wear, but a larger difference in axial elongation between groups was evident at the later follow-up visits. This highlights the importance of considering both short- and long-term outcomes when evaluating myopia control interventions.

The study also highlights that treatment efficacy may not be uniform across all patients. Children with steeper corneas experienced less axial elongation with orthokeratology, suggesting that baseline corneal shape could influence treatment outcomes. However, the relatively small number of participants completing the 11-year follow-up means this finding should be interpreted cautiously. Overall, these results support orthokeratology as a long-term myopia management strategy and provide clinicians with realistic expectations regarding the magnitude of axial length changes that may be achieved over extended periods of treatment.

This study provides the longest prospective follow-up of orthokeratology for myopia control reported to date, but several questions remain. Although the treatment effect increased from 0.22 mm at 2 years to 0.69 mm at 11 years, much of this benefit was achieved during the initial years of treatment, with smaller incremental gains thereafter. Further research is needed to determine whether this pattern reflects changes in treatment efficacy, the natural slowing of axial elongation with age, or a combination of both factors.

Larger long-term studies would help to confirm these findings, as the relatively small number of participants attending the final 11-year visit limits confidence in the generalizability of the results.

The finding that children with steeper corneas showed less axial elongation with orthokeratology also warrants further investigation. Future studies could determine whether this relationship can be replicated in larger cohorts and different ethnic populations, as this study was conducted exclusively in White European children. Better understanding of factors associated with treatment response could help clinicians identify which patients are most likely to benefit from long-term orthokeratology treatment.

Significance: The myopia control effect of orthokeratology accrues over time, with 11 years of lens wear providing a cumulative absolute reduction in axial elongation of −0.69 mm in comparison with spectacle lens wear. Steeper corneas are likely to benefit from enhanced myopia control efficacy.

Purpose: To compare axial length growth between a group of orthokeratology contact lens wearers and a control group of distance single-vision lens wearers over an 11-year period.

Methods: White European subjects 6 to 12 years old with myopia −0.75 to −4.00DS and astigmatism ≤1.00DC were prospectively allocated orthokeratology or distance single-vision spectacle correction for 2 years. Axial length measurements (Zeiss, IOLMaster) were taken at 6-month intervals during the initial 2 years of the study. Subjects were contacted approximately 5 and 9 years later (i.e., 7 and 11 years after the beginning of the study, respectively) and axial length measurements were repeated.

Results: Thirty-one orthokeratology and 30 control subjects were initially recruited, but only 10 orthokeratology and 15 control subjects attended the 11-year visit. In comparison with the control group, the change in axial length for the orthokeratology group was reduced by 0.04, 0.10, 0.14, 0.22, 0.45, and 0.69 mm after 0.5, 1, 1.5, 2, 7, and 11 years of lens wear, respectively. Significant differences between groups were found in mean unadjusted changes in axial length at the 1-, 1.5-, and 2-year time points (unpaired t-test, p < 0.05), whereas standard contrasts revealed statistical differences between groups in the estimated marginal means of the change in axial length at the 7- and 11-year time points (p < 0.05).

Conclusions: Eleven years of orthokeratology lens wear provided a substantial slowing in the axial elongation of the eye, with a treatment effect of up to 0.69 mm after 11 years of lens wear in comparison with single-vision lens wear.

[Link to open access paper]