Crystalline lens power reduction in pediatric patients treated with 0.01% atropine may explain the treatment’s anti-myopia effect, according to a study published in Ophthalmic and Physiological Optics.
Researchers enrolled 120 children with progressive myopia (≥0.5 diopters [D]/year) in a nonrandomized clinical trial and assigned participants to treatment with 0.01% atropine 2 times daily (n=70) or to a control group with no treatment (n=50). Patients underwent cycloplegic autorefraction and ocular biometry assessment, which included axial length, anterior chamber depth (ACD) and lens thickness measurements at baseline and at the 1-year follow-up visit. The team monitored treatment compliance by having participants return with their atropine bottles at 2 weeks, 2 months, 6 months, and 1 year. The investigators monitored biometry changes and calculated changes in lens power.
Overall, mean myopia progression was significantly reduced among individuals treated with 0.01% atropine compared with control group participants (−0.18 vs −0.59 D; P <.001) at 1 year. Axial length increase was was also significantly reduced in the atropine 0.01% group compared with the control group (0.21 vs 0.29mm; P <.001).
Crystalline lens power significantly reduced among the atropine 0.01% group compared with the control group (−0.67 vs −0.28 D; P <.001) and lens thicknesses were significantly different between the 2 groups (P =.02). No differences were noted in anterior chamber depth or keratometry between the groups.
“Lens power loss is a well-known phenomenon that occurs throughout life,” the study authors explain. “This power loss plays an essential role during the refractive homeostasis, when an emmetropized eye tries to retain a refractive error of low hypermetropia by closely coordinating its refractive power loss with its axial growth. Disruptions to this process may eventually lead to the development and progression of myopia.”
Study limitations include non random assignments to treatment groups and a failure to evaluate lens power changes following treatment cessation.
Saxena R, Gupta V, Dhiman R, et al. Effect of low-dose atropine (0.01%) on crystalline lens power among school-aged children with progressive myopia. Ophthalmic Physiol Opt. Published online June 23, 2023. doi:10.1111/opo.13192