Abstract
Purpose:
Peripheral refractive error degrades the quality of retinal images and has been hypothesized as a potential factor to stimulate the development of refractive error. Various contact lens designs based on the hypothesis have shown the efficacy of controlling myopia progression. The aim of the study was to evaluate the impact of orthokeratology lens (OK lens) on the peripheral wavefront aberration in myopic eyes.
Methods:
We conducted a cross-sectional study to evaluate the effect of OK lens on the peripheral aberration profile of myopic subjects in adolescents. Study subjects were divided into two groups; one was OK lens group and the other was myopic patients who did not experience the OK lens correction. A custom-developed Shack-Hartmann aberrometer was used to measure ocular wavefront aberrations along different horizontal retinal eccentricities with ten degree step across the central 30 degrees of visual field. The study subjects maintain their natural foveal fixation while the aberrometer is rotated around the eye for the off-axis measurements. Wavefront refraction for each retinal eccentricity was quantified over 4 and 6 mm pupils.
Results:
The mean refractive error was -1.92D ± 0.83 in the OK lens group and -5.84D ± 2.47 in the naked eye group, respectively. Hyperopic defocus at the peripheral visual field in the myopic eyes increases with increasing amounts of forveal refractive error. These effects varied with the degree of the corrected power after a treatment of OK lens. Significant difference (p < 0.05) in the value of defocus was found at the peripheral retinal eccentricity in the OK lens group compared to the naked eye group. In the analysis of high order aberration, values of on-axis and off-axis showed a different tendency along with the symmetry of each aberration.
Conclusions:
OK lens treatment is found to be effective in reducing the degree of peripheral hyperopic defocus in myopic eyes.