Effectiveness of orthokeratology in controlling myopia in adolescents aged 6-18 years: a systematic review and meta-analysis.

BACKGROUND

Global childhood myopia is rising, with longer axial length increasing ocular risks. Orthokeratology corrects vision and may slow axial elongation via peripheral defocus, but the efficacy of newer OK lens designs and long-term persistence of effect remain to be comprehensively evaluated.

METHODS

Adhering to PROSPERO and PRISMA 2020, PubMed, Embase, Web of Science, Scopus, and Cochrane Library were searched through 18 April 2025. Included studies prospectively compared axial-length changes in children (6-18 years) with OK versus single-vision spectacles, soft contact lenses, or conventional OK. Hartung-Knapp-adjusted random-effects meta-analyses were performed, with subgroup, sensitivity, and leave-one-out analyses addressing heterogeneity.

RESULTS

Fifteen trials (1,065 participants) met inclusion criteria. At 12 ± 2 months, OK slowed axial elongation by a pooled mean difference (MD) of - 0.15 mm (95% CI - 0.20 to - 0.10; I2 = 90.8%). Five studies with ≥ 24-month follow-up showed a sustained benefit (MD - 0.19 mm, - 0.32 to - 0.06; I2 = 79%). Four head-to-head trials suggested modified OK designs (e.g., smaller optical zones, higher compression factors) provided an additional - 0.12 mm (- 0.23 to - 0.01) at one year, after excluding one discordant soft-lens study. Funnel plots and Egger's tests indicated no small-study bias. Most studies had low risk of bias; limitations included lack of masking and predominantly East-Asian samples.

CONCLUSIONS

Axial elongation in myopic children is reduced by approximately 0.15 mm in the first year with OK, and this effect persists for up to three years. Modified lens designs may offer additional benefit. Larger, multi-ethnic trials with long-term follow-up and standardised safety reporting are needed.