LASIK手术对人眼角膜生物力学性能的影响

Effects of LASIK on Biomechanical Properties of Human Cornea

目的研究人眼角膜在准分子激光角膜原位磨镶术(laser in situ keratomileusis,LASIK)术后生物力学性能的变化并预测术后角膜刚度。方法利用可视化角膜生物力学分析仪(Corvis ST)的测量结果,计算表征角膜刚度的瞬时刚度系数(STSC)和表征黏性的能量吸收面积(Aabsorbed),分析屈光术后角膜刚度和黏性的变化规律。结果LASIK术后角膜STSC和Aabsorbed较术前差异具有统计学意义(P <0. 05),获得角膜刚度预测公式为:S术前=1. 055bIOP术前+0. 015CCT术前,S术后=0. 937S术前+0. 019CCT术后。结论 LASIK手术不仅改变角膜厚度,也降低角膜的刚度和黏性。预测术后角膜刚度可为临床手术的设计提供指导,提高手术安全性。

Objective To study the changes in biomechanical properties of human cornea after laser in situ keratomileusis(LASIK)and predict corneal stiffness after the LASIK surgery.Methods According to the measurement results from corneal visualization scheimpflug technology(Corvis ST),the corneal tangent stiffness coefficient(STSC)and energy absorbed area(Aabsorbed)were calculated.The change patterns of corneal stiffness and viscosity after refractive surgery were analyzed.Results The difference of corneal STSCand Aabsorbedbefore and after LASIK had a statistical significance(P<0.05).The obtained formula for predicting corneal stiffness after refractive surgery was:Sbefore surgery=1.055 b IOPbefore surgery+0.015 CCTbefore surgery,Safter surgery=0.937 Sbefore surgery+0.019 CCTafter surgery.Conclusions LASIK surgery not only changes corneal thickness,but also reduces corneal stiffness and viscosity.Prediction of corneal stiffness after surgery can provide guidance for the design of clinical surgery and improve the safety of surgery.