Spherical aberration changes of eye and anterior surface of cornea after LASIK

Objective To analyze the spherical aberration changes of the eye and anterior surface of cornea for myopia after laser in situ keratomileusis (LASIK) with OPD-SCAN.Methods Preoperative and postoperative aberration examinations were performed on 73 eyes of 40 myopia patients,which were continuously selected and assigned to three different groups according to the diopter:low diopter,media diopter and high diopter.The spherical aberration of the eye and anterior surface of cornea in 6mm pupil were computed.Comparison of the spherical aberration among preoperation,one week after operation and three months after operation were adopted with one-way ANOVA.Post Hoc Tests were used to compare every two groups of them.Linear correlation was used to analyze the relationship between the diopter before the surgery and the spherical aberration after the surgery.t-test was performed to analyze the differences of the spherical aberration of the eye and anterior surface of cornea between three months after LASIK and those of preoperation.Results Spherical aberration of eye and anterior surface of cornea showed signifcant differences among preoperation,one week and three months postoperatively in each group(P0.01).The spherical aberration RMS of the eye and anterior surface of cornea were directly correlated with the diopter before the surgery (P0.01).The differences of spherical aberration of eye and anterior surface of cornea between 3 months postoperation and preoperation in each group were statistically different.Conclusion LASIK can induce the increasing of spherical aberration of the eye and anterior surface of cornea.And it has positive correlation with preoperative diopter.The spherical aberration of anterior surface of cornea increases more than that of the eye.