Orthokeratology, Atropine Combination Slows Axial Growth in Children With Myopia

Axial elongation in children with myopia can be slowed by the addition of 0.01% atropine to orthokeratology treatment.

Orthokeratology (ortho-k) treatment combined with 0.01% atropine drops demonstrates better myopia control efficacy than orthokeratology treatment alone, according to findings published in BMC Ophthalmology.

Researchers included 53 children with myopia (spherical equivalent refraction, -1.00 to -4.00 diopters [D]) in a prospective, randomized, double-blinded, placebo-controlled trial and randomly assigned them to treatment with a combination of ortho-k and 0.01% atropine (n=27; mean age, 10.07 years) or ortho-k and a placebo eye drop (n=26; mean age, 9.80 years). The children wore the lenses every night for 8 hours and underwent axial length (AL), corneal power, and anterior chamber depth measurements at baseline and at 1-day, 1-week, 2-, 4-, 8-, and 12-month follow-up visits. Treatment compliance was determined by the amount of eye drops that remained during follow-up visits.

Participants who used atropine 0.01% in conjunction with orthokeratology experienced an axial elongation of 0.10 mm compared with 0.20 mm in participants treated with the placebo drop (P =.01) after 12 months. The change in AL between the 2 groups, however, was only significantly different during the first 4 months (median  -0.01 mm; 95% CI,-0.06-0.04 vs median 0.04 mm; 95% CI, 0.02-0.09; P =.04). 

Pupil diameter increased by 0.45 mm at the 4 month visit (P <.001) and remained stable in participants treated with ortho-k and atropine 0.01%. This metric remained stable in participants treated with the placebo. The accommodative amplitude remained stable in both groups from baseline to 12 months (all P >.05).

The mechanisms by which the combination of OK lens and 0.01% atropine was more effective in slowing axial elongation than OK lens alone remains uncertain. 

A total of 13.3% of children treated with atropine and 10% of children treated with placebo drops reported mild photophobia in bright sunlight, but no other adverse events were reported. 

According to the researchers, “The mechanisms by which the combination of OK lens and 0.01% atropine was more effective in slowing axial elongation than OK lens alone remains uncertain. 0.01% atropine in the combination group significantly increased pupil diameter in children, which may facilitate the effect of OK lens[es] to slow axial elongation through both pharmacological and optical mechanisms.”

Study limitations include a small sample size based on crossover design, and the lack of a control group consisting of spectacle wearers.

References:

Yu S, Du L, Ji N, et al. Combination of orthokeratology lens with 0.01% atropine in slowing axial elongation in children with myopia: a randomized double-blinded clinical trial. BMC Ophthalmol. Published online November 15, 2022. doi:10.1186/s12886-022-02635-0