激光斜入射和反射对角膜屈光手术后人眼成像质量的影响

以Kooijman眼模型为基础,根据Jimenez的理论及临床上应用的Munnerlyn理论,分析了激光在角膜前表面的斜入射和反射对角膜屈光手术后人眼成像质量的影响。研究表明,激光的斜入射和反射会引起一定的术后欠矫,但是影响不大,对于-9D的术前屈光不正,由激光能量损失引起的欠矫也只有-0.6D;激光角膜手术本身会使术后角膜前表面的非球面系数变大。随着术前屈光不正的增大,非球面系数由术前的负值变为正值,使得术后的人眼球差增大。考虑了激光斜入射和反射后的术后非球面系数与Munnerlyn公式的预期值差别不大,术后非球面系数的大小与光区的关系不大。

Effects of the Reflection Losses and Nonnormal Incidence of Laser on the Eye's Visual Quality after Refractive Procedure on a Cornea

Based on the eye model of Kooijman,the effects of the reflection losses and nonnormal incidence of laser on the human eye's visual quality after refractive procedure on a cornea were analyzed by comparing the J.R.Jimenez's theory and Munnerlyn's.The reflection losses and nonormal incidence on the anterior cornea lead to the under-correction of the post-surgery eye.With the 6 mm diameter of the optical zone,when the refractive error of the eye before surgery is-9D,the under-correction is only-0.6D.The corneal asphericity after refractive surgery increases for myopia.With the increase of the refractive error before refractive surgery,the asphericity of the anterior cornea changes from negative to positive,which leads to the increase of the spherical aberration.There is no large difference between the asphericities obtained by Munnerlyn's theory and Jimenez's.The diameter of the optical zone has little effect on the post-surgery p-value.