Abstract:AIM: To investigate the decentration of the treatment zone(TZ)and the early impact on corneal higher-order aberrations(HOAs)induced by orthokeratology(OK)lenses fitted with digital corneal topography.
METHODS: A retrospective longitudinal clinical study was conducted on 28 patients(28 right eyes)who were digitally fitted with OK lenses at the Laser Vision Center of Xi'an No.1 Hospital since 2023. Longitudinal measurements were taken at baseline, 1 wk, 1 and 3 mo post-treatment to assess changes in TZ diameter, decentration magnitude and direction. Furthermore, changes in corneal HOAs were observed, and correlations of decentration with each HOAs were also analyzed.
RESULTS: The mean age of patients was 10.29±2.00 years, with 15 males and 13 females, and the average baseline spherical equivalent was -2.92±0.94 D. The average TZ diameters at 1 wk, 1, and 3 mo were 3.64±0.58, 3.83±0.57, and 3.69±0.55 mm, respectively, with no statistically significant differences between 1 wk and 3 mo. Horizontal decentration values were -0.43±0.28, -0.38±0.33, and -0.31±0.37 mm after wearing lenses for 1 wk, 1 and 3 mo, respectively, while vertical decentration values were -0.33±0.20, -0.33±0.23, and -0.36±0.23 mm across the same time points. The TZ consistently decentered inferotemporally, and changes in both horizontal and vertical decentration over time were not statistically significant(Fhorizontal=1.416, Phorizontal=0.252; Fvertical=0.126, Pvertical=0.882). Significant increases in total corneal HOAs, coma, and spherical aberration were observed at 5 mm optical zone post-wear(F=45.695, 33.401, and 45.091, all P<0.001). Vertical decentration at 1 wk and 1 mo was negatively correlated with total HOAs and coma(all P<0.05), while horizontal decentration at 3 mo showed a weak negative correlation with spherical aberration(P=0.037).
CONCLUSION: Digitally-fitted OK lenses achieved stable TZ diameter by 1 wk post-wear, with minor inferotemporal decentration. Early post-wear corneal total HOAs, coma and sphercal aberration increased significantly, and vertical downward decentration was associated with elevated total HOAs and coma. However, correlations between decentration and HOAs weakened by 3 mo.
