基于屈光手术的角膜切削模型和临床测量的波前像差数据,分析了矫正近视散光的常规屈光手术中切削偏心对波前像差的影响。结果表明,切削偏心主要会引起彗差的增大,引入彗差与偏心程度成线性关系,与被矫正的近视散光的屈光度也近似成线性关系。3-5阶像差中,除彗差以外的其它高阶像差并不会随着切削偏心的增大而显著增大。屈光手术后高阶像差的增大主要是切削偏心、激光斜入射和角膜愈合反应等多重因素导致的。

Based on the excimer laser cornea correction mathematical model and the clinical wave-front aberration data,the influence of treatment decentration on wave-front aberration in conventional laser refractive surgery is studied. The result reveals that treatment decentration may induce the distinct increase of coma. The induced coma is nearly proportional to the treatment decentration and the corrected refraction. But other Zernike coefficients except for coma from third- to fifth-order aberrations approximatively maintain constant with the increase of treatment decentration. The increase of higher-order aberrations after refractive surgery may be attributed to the treatment decentration,the effect of oblique incidence of laser spot and the effect of biological response of the cornea.