Orthokeratology Combined With Atropine Slows Axial Growth in Children With Myopia

Mid section view of a doctor putting eye drops in a girl's eye
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Slower axial elongation after atropine with orthokeratology treatment may be associated with increased pupil dilation and greater choroidal thickening.

Atropine with orthokeratology (AOK) treatment slows axial elongation more than using orthokeratology alone (OK) in children with myopia, according to a 2-year study published in Contact Lens and Anterior Eye

Researchers conducted a 2-year randomized clinical trial of 69 children with myopia (1.00 – 4.00 D, inclusive). They randomly assigned participants to either an AOK (n=34, mean age 9.2±1.0 years, 20 girls) or OK group (n=35, 9.1±1.2 years, 19 girls). AOK treatment involved applying 0.01% atropine into each eye, 10 minutes prior to nightly 4-zone OK lens wear. The team measured axial length (the primary outcome), pupil size, and choroidal thickness at 1-month and at 6-month intervals until the 2-year study conclusion. 

Researchers observed slower axial elongation in the AOK group compared with the OK group over the course of the 2-year study duration (0.17±0.03 vs 0.34±0.03 mm; P <.001), revealing a difference of 0.18±.05 mm between the cohorts. They also noted larger increases in mesopic and photopic pupil size among children in the AOK cohort compared with the OK group (P =.003 and P <.001, respectively). Children in the AOK group also experienced greater choroidal thickening compared with OK group participants (difference 31.6±5.0 µm; P <.001).

Slower axial elongation among AOK participants was associated with a larger increase in photopic pupil size and greater choroidal thickening, according to the report. 

“An additive effect was observed following combined treatment of 0.01% atropine and ortho-k, as axial elongation was slowed by 0.18 mm more with combined treatment of 0.01% atropine and ortho-k than with ortho-k alone over two years,” according to the researchers. “Slower axial elongation following 2-year AOK treatment may result from increased pupil dilation and a thickening in the choroid observed in the AOK group.”   

This study was limited by a high dropout rate (22%).

Disclosure: This research was supported by multiple sources. Please see the original reference for a full list of disclosures.   


Tan Q, Ng ALK, Cheng PMG, Woo VCP, Cho P. Combined 0.01% atropine with orthokeratology in childhood myopia control (AOK) study: a 2-year randomized clinical trial. Cont Lens Anterior Eye. Published online May 31, 2022. doi:10.1016/j.clae.2022.101723