Effect of orthokeratology combined with unilateral 0.01% atropine on children with unilateral myopia

OBJECTIVE: To investigate the efficacy of orthokeratology combined with unilateral 0.01% atropine in children with unilateral myopic anisometropia. METHOD: In this prospective cohort study, 93 children (aged 8-16 years) with unilateral myopia and fitted with orthokeratology lenses at Xi'an First Hospital (2022-2024) were included. The spherical equivalent (SE) of the myopic eye ranged from -4.00 D to -0.75 D, while that of the non-myopic eye ranged from -0.50 D to +0.75 D. Based on patient/parental choice, participants were assigned to either an intervention group, in which the non-myopic eye received nightly 0.01% atropine (one drop), or a control group with no intervention in the non-myopic eye. Changes in axial length (AL) of both eyes and in the interocular AL difference before and after lens wear were compared. Data were analyzed using paired t-tests, independent t-tests, and linear regression. RESULTS: A total of 47 participants in the intervention group and 46 in the control group completed the 12-month follow-up. Intergroup comparison: Compared with the control group, the intervention group showed significantly slower AL elongation in the non-myopic eye (0.13 ± 0.12 mm/year vs. 0.45 ± 0.25 mm/year, P = 0.003). No statistically significant difference was found in AL elongation of the myopic eye between the two groups (0.15 ± 0.17 mm/year vs. 0.11 ± 0.19 mm/year, P = 0.207). Intragroup comparison: In the intervention group, the difference in AL elongation between the two eyes was not statistically significant. In the control group, AL elongation of the myopic eye was significantly slower than that of the non-myopic eye (P < 0.001). Change in interocular AL difference: After 12 months, the interocular AL difference remained stable in the intervention group (0.92 ± 0.57 mm vs. 0.94 ± 0.57 mm), whereas it decreased significantly in the control group (0.99 ± 0.56 mm vs. 0.66 ± 0.53 mm, P < 0.001). CONCLUSION: For children with unilateral myopia wearing Orthokeratology lenses, the addition of unilateral 0.01% atropine to the contralateral eye can effectively slow AL elongation in the non-myopic eye.