A Method to Estimate the Efficacy of Orthokeratology Lenses in Slowing Myopia Progression.

Purpose: To estimate the efficacy of orthokeratology contact lenses in slowing myopia progression.

Methods: Prospective data from 101 to 88 children, aged 6 to 12 years and with myopia between -0.50 and -5.00 D, who completed 2 years of orthokeratology and single-vision spectacle lens wear, respectively, were analyzed post hoc. The relationship between changes in mean spherical refractive error (MSE) and axial length (AL) in the control group (spectacle wearers) was assessed and subsequently used to convert changes in AL into changes in MSE for the orthokeratology group.

Results: Relatively strong correlations were found between changes in MSE and AL relative to baseline for the control group at all time points, including 0.5-, 1-, 1.5-, and 2-year intervals after lens wear (all P <0.001). The estimated mean changes in MSE (± SD) at 24 months in comparison with baseline for orthokeratology and control groups were -0.77±0.51 and -1.24±0.71 D, respectively. Thus, it is estimated that orthokeratology lenses slow the increase in MSE versus the control by -0.47 D.

Conclusions: This study estimates that orthokeratology lenses reduce myopia progression by -0.47 D after 2 years of lens wear in comparison with spectacle wear. These results might be useful for eye care practitioners engaged in fitting orthokeratology lenses for myopia management.