Repeated low-level red-light therapy combined with orthokeratology for myopia control in Spain: a randomised controlled study.

Abstract

To evaluate the 12-month efficacy and safety of repeated low-level red-light (RLRL) therapy combined with orthokeratology (ortho-k) (RCO) for controlling myopia in Spanish children. In this single-site, randomised, parallel-group, non-blinded clinical trial (NCT06899139), eligible myopic children aged 10-13 years were recruited and assigned randomly either to the RCO group or the ortho-k group. Follow-up assessments were conducted at 6, 9 and 12 months after baseline. The primary outcome and secondary outcome were the axial length (AL) and macular thickness (MT) changes at 12 months estimated by longitudinal mixed model. All participants (n=26; 11 in the RCO group and 15 in the ortho-k group) were included in the analysis. After 12 months, the adjusted mean AL change was -0.124 mm (95% CI -0.164 to -0.084) in the RCO group, whereas the ortho-k group continued to exhibit a modest axial elongation of 0.102 mm (95% CI 0.068 to 0.136). The adjusted mean difference in AL change was -0.226 mm (95% CI -0.279 to -0.174) between the groups (p<0.001). Additionally, the adjusted mean change in MT showed no significant difference between groups at 12 months. In the RCO group, 80% of children achieved AL shortening >-0.05 mm, whereas no children in the ortho-k group showed AL shortening. No severe adverse events were reported during the study. Combining RLRL therapy with ortho-k is an effective and safe myopia control strategy in Caucasian Spanish children, supporting the potential generalisability of the synergistic effect across diverse ethnic groups.