近视及近视散光眼高阶像差的研究

Highter Order Aberrations in Myopia and Myopic Astigmatism Eyes

目的研究瞳孔直径、近视度数、散光大小对近视及近视散光患者眼高阶像差的影响,探讨高阶像差与最佳矫正视力的关系。方法随机选取欲行准分子激光手术的203只眼进行检查,按近视度数分为高度(>-6.0D)、中度(-3.0D～-6.0D)、低度(<-3.0D)近视组,按散光度数分为Ⅰ组(散光≥-0.75D)、Ⅱ组(散光<-0.75D),像差数据由Hartmann-Shack原理设计的德国WASCA波阵面像差仪测得。对所得高阶像差值在瞳孔直径为4.0mm、5.0mm、6.0mm时进行统计分析。结果总高阶相差、水平彗差、垂直彗差和球差均随瞳孔直径的增大而增大;各近视组的高阶像差值均无显著性差异(P>0.05);在瞳孔直径为5mm和6mm时两个散光组的总高阶像差值和垂直彗差值差异显著(P<0.05);在瞳孔直径为5mm和6mm时垂直彗差与最佳矫正视力正相关(r=0.576,0.695,P<0.01),球差与最佳矫正视力负相关(r=-0.580,-0.763,P<0.01)。结论瞳孔大小影响近视及近视散光患者眼的各类高阶像差;散光影响垂直彗差和总高阶像差;对欲行个体化角膜切削的近视及近视散光患者,保留垂直彗差而完全矫正球差可能有助于视觉质量的提高。

Objective To analyze the effects of pupil size, myopia and astigmatism on the higher order ocular aberrations in eyes with myopia and myopic astigmatism,and determine relationship between higher order aberrations and best corrective vision acuity （BSCVA）. Methods Using a Hartmann-shack method,203 myopia and myopic astigmatism eyes were evaluated before LASIK. According to the degree of myopia and astigmatism,the subjects were divided into following groups：high myopia （〉-6.00 D） ,moderate myopia （-3.00 D-6.00 D） and low myopia （〈-3.00 D）; astigmatism group Ⅰ（≥-0.75 D）,astigmatism group Ⅱ （〈-0.75 D）. The root mean square （RMS） values of higher order aberrations for each subject with pupil diameters of 4.0 mm, 5.0 mm, 6.0 mm were calculated. SPSS 11.5 was used for statistical analysis. Results Total higher order aberrations,spherical aberration,horizontal primary coma,and vertical primary coma,were increased significantly with increasing pupil size. However,they were not affected by the degree of myopia. In 5.0 mm and 6.0 mm pupil,astigmatism affected total higher order aberrations and vertical primary coma, but horizontal primary coma and spherical aberration. In 5.0 mm and 6.0 mm pupil, there was a positive relationship between vertical primary coma and BSCVA （r = 0.576,0.695, P 〈 0.01 ）, a negative relationship between spherical aberration and BSCVA（r = -0.580,-0.763 ,P 〈 0.01 ）. Conclusion Pupil size affected all types of higher order aberrations. Astigmatism affected total higher order aberrations and vertical primary coma. Maintaining vertical primary coma and correcting spherical aberration completely for myopia and myopic astigmatism may be the best choice for customized cornea laser ablation surgery.