Identify the Relationships Between Orthokeratology Lens Decentration and Myopia Control Efficacy in Children by Using Pentacam

PURPOSE: To determine orthokeratology (ortho-k) lens decentration and its relationships with annual axial length (AL) changes in children treated with ortho-k. METHODS: This retrospective study included children aged 9 to 15 years treated with ortho-k for at least 1 year. Lens decentration was measured using Pentacam based on the relative positions of the corneal thinnest point, pupil center, and visual center. Annual AL change was analyzed using regression models adjusted for age and target power. RESULTS: In total, 71 eyes from 37 patients (mean age, 10.9 years) were included in the final analysis. The mean follow-up time was 35.0 months. The mean annual AL change was 0.11 mm. According to the customized formula based on the pupil or visual center, greater horizontal and vertical vectors and a larger total distance of decentration were associated with less annual AL change. CONCLUSION: Greater temporal and inferior vectors, as well as a larger total distance of decentration, are associated with greater myopia control efficacy. These findings will help to facilitate the prescription and future design of ortho-k lenses to improve myopia control efficacy.