Two-Dimensional Peripheral Refraction and Higher-Order Wavefront Aberrations Induced by Orthokeratology Lenses Decentration.

Abstract

The purpose of this study was to explore two-dimensional peripheral refraction and higher-order aberrations (HOAs) induced by orthokeratology lens decentration. Two-dimensional peripheral refraction and HOAs in a rectangular field (horizontally 60 degrees and vertically 36 degrees) were obtained using an open-view Hartmann-Shack wavefront sensor. The peripheral field was divided into 8 regions according to a combination of superior (UZ) or inferior (LZ) and a value, 1 (T25 to T30), 2 (T20 to T25), 3 (N20 to N25), or 4 (N25 to N30). The decentration of the lens was evaluated based on the change of power in the front of the tangential corneal map. All measurements were taken at the baseline and 1 month after lens fitting. In total, 134 myopic children (age = 12.47 ± 1.70 years, SER = -2.44 ± 1.10 diopters [D]) were recruited. In general, horizontally asymmetrical change was observed in relative peripheral refraction (RPR), spherical aberration (SA), and horizontal coma. The root-mean square of higher order aberration (RMSHOA) and vertical coma demonstrated radial symmetrical change and vertically asymmetric change, respectively. Relative peripheral myopia was significantly increased after the treatment, with more myopic refraction in the temporal side. RPR changes in UZ2, UZ3, UZ4, LZ1, and LZ2 were related to the amount of lens decentration (r ≈ 0.4, P<0.05). All HOAs increased after lens fitting (around 0.03 um, 0.02 um, 0.04 um, and 0.41 um for SA, horizontal COMA, vertical COMA, and RMSHOA in the periphery region). RPR and HOAs are related to lens decentration, which might contribute to the efficacy of orthokeratology. The study found a decentration-related optical feature after 1 month of lens wear, which is a suggested protective factor in myopia treatment. The findings might provide new insights for customized contact lens myopia treatment based on optics.