Efficacy, Safety and Acceptability of Orthokeratology on Slowing Axial Elongation in Myopic Children by Meta-Analysis.

PURPOSE To compare the efficacy, safety and acceptability of a treatment group (Orthokeratology) to a control group (single vision Spectacles) on slowing axial elongation in children. METHODS We searched studies in MEDLINE, EMBASE and the Cochrane Library up to January 2015 for randomized controlled trials (RCTs) and observational studies. We pooled the mean differences between the Orthokeratology and Control groups for axial elongation and the OR for rates of adverse events and dropout. RESULTS Three RCTs and six cohort studies with 667 children aged 6-16 years old were included. Two years' mean differences in axial elongation were -0.27 mm (95% confidence intervals [CI], -0.32 to -0.23) in all studies, -0.28 mm (95% CI, -0.35 to -0.20) in RCTs and -0.27 mm (95% CI, -0.32 to -0.22) in cohort studies (p < 0.01). At 6 months, 1 year, 1.5 years and 2 years, mean differences in axial elongation were -0.13 mm, -0.19 mm, -0.23 mm, and -0.27 mm (p < 0.01), respectively. The effect was greater in Asian children than Caucasian (-0.28 mm versus -0.22 mm) and in children with moderate to high myopia when compared to children with low myopia (-0.35 mm versus -0.25 mm). Orthokeratology had more non-significant adverse events (odd ratio [OR], 8.87; 95% CI, 3.79-20.74; p < 0.01) but comparable dropout rates (OR = 0.84, 95% CI, 0.40-1.74, p = 0.64) than control. CONCLUSION Orthokeratology has significantly greater efficacy in controlling axial elongation in children compared to Spectacle correction. The safety and acceptability results are good, and there appears to be a greater myopia control effect in Chinese children compared to Caucasians, and in those with higher initial myopia.