Analysis of the change of corneal higher-order aberrations after laser in situ keratomileusis

Objective To investigate the change of corneal higher-order aberrations (HOA) after laser in situ keratomileusis. Methods Retrospectively analyzed 145 eyes from 75 patients after myopic LASIK and compared the pre-and post-operative values of the asphericity (Q),RMSh,RMS3-RMS7,spherical aberration, coma and trefoil. To screen the influence factors to the increment of every component of corneal HOA by using the linear multifaetor regression.Results The corneal HOA has no correlation with age. The post-operative values of every component of corneal HOA are mainly affected by the pre-operative value, attempted spherical equivalent (SE), and oblation zone (OZ). The higher the pre-operative value, the higher the attempted SE and the smaller the OZ, the higher the post-operative value. The incrernents of Q value, RMSh and the spherical aberration depend on the attempted SE and OZ. The increments of coma and trefoil have no correlation with the oblation zone. Compared with the larger oblation zone (6.0mm), every diopter correction with the smaller OZ will result in a significant higher post-operative corneal HOA and more positive post-operative Q value.Conclusion The attempted SE and the OZ are the main reasons responsible for the increase of the corneal HOA after LASIK. Key words: LASIK; Wavefront-aberration; Corneal topography