Peripheral refraction, relative peripheral refraction, and axial growth: 18-month data from the randomised study-Clinical study Of Near-sightedness; TReatment with Orthokeratology Lenses (CONTROL study).

We found no correlations between change in RPR and treatment efficacy defined as change in AL. Interestingly, our results suggest that the central emmetropisation that occurs during OKL-use accounts for most of the optical changes and to a lesser extent the mid-peripheral plus-zone of the lens.