Changes and Diurnal Variation of Visual Quality after Orthokeratology in Myopic Children

Purpose. To assess the changes and the diurnal variation of visual quality after orthokeratology in myopic children. Methods. Forty-four eyes of 22 subjects with a mean age of 10.55 ± 1.53 years (8 to 14 years) were enrolled in this prospective study. Their spherical equivalent ranged from −1.25 to −4.25 diopters (D) and astigmatism was less than 1.00 D. Parameters including corneal curvature, ocular objective scatter index (OSI), the modulation transfer function (MTF), root mean square of ocular and corneal wavefront aberrations, and contrast sensitivity function (CSF) were measured before and at two time points during the same day after 1 month of orthokeratology. Results. After orthokeratology, uncorrected visual acuity (UCVA) and spherical equivalent were significantly improved from baseline (P