The Effects of Overnight Orthokeratology Lens Wear on Ocular Scatter

ABSTRACT

PURPOSE: To evaluate the change of visual quality after wearing orthokeratology lenses overnight. METHODS: This study included 13 patients (24 eyes) who wore orthokeratology lenses for the first time. Visual quality was assessed with the optical quality analysis system (OQAS) using the double-pass technique. The value of modulation transfer function (MTF) cutoff, Strehl ratio, and objective scatter index (OSI) were measured at baseline and 4 weeks after wearing the lenses. RESULTS: The mean spherical equivalent decreased from -2.70 +/- 1.03 diopters (D) to 0.03 +/- 0.36 D after 4 weeks of wearing orthokeratology lenses and uncorrected visual acuity improved from log MAR 0.88 +/- 0.17 to log MAR 0.03 +/- 0.04. The MTF cutoff decreased from 38.20 +/- 11.01 to 34.79 +/- 10.30 and the Strehl ratio decreased from 0.24 +/- 0.07 to 0.21 +/- 0.07 but without statistical significance. The OSI significantly increased from 0.38 +/- 0.19 to 0.72 +/- 0.40 after wearing orthokeratology lenses. CONCLUSIONS: Orthokeratology lenses were effective for correction of myopia and astigmatism. The OSI increased after wearing the lenses, but MFT cutoff and Strehl ratios were not affected.