白内障人群角膜球差的测量及其在非球面人工晶状体选择中的意义

目的调查我国白内障人群角膜前表面球差的分布特点，探讨年龄、角膜散光、角膜非球面Q值、平均角膜曲率及眼轴长度等因素是否对角膜前表面球差产生影响，为白内障手术非球面人工晶状体的选择提供参考。方法使用iTraee像差仪测量572例572眼角膜前表面球差、角膜非球面Q值、平均角膜曲率，使用IOLMaster测量眼轴长度。分析角膜前表面球差的统计学分布特征及其与年龄、角膜非球面Q值、平均角膜曲率、角膜散光及眼轴长度之间的关系。结果角膜前表面球差为（o．25±0．08）μm，与年龄、角膜散光不相关（P〉0．05），与角膜非球面Q值和平均角膜曲率正相关（P〈0．05），与眼轴长度负相关（P〈0．05）。角膜非球面Q值（Beta=0．837，P〈0．001）、平均角膜曲率（Beta=0．250，P〈0．001）对角膜前表面球差有显著性影响。按角膜非球面Q值分为3组（G1：-1〈Q〈0；G2：Q=0；G3：Q〉0），各组间角膜前表面球差差异有统计学意义（P〈0．05）。结论角膜前表面球差存在明显的个体差异性，且其与角膜非球面Q值、平均角膜曲率正相关，与眼轴长度负相关，受角膜非球面Q值和平均角膜曲率影响显著，所以白内障术前精确测量角膜前表面球差对于非球面人工晶状体的个体化选择非常重要。

The measurement of corneal spherical aberration in the patients with cataract and the application in the choice of aspherical intraocular lens

Objective To investigate the distribution of spherical aberration of anterior corneal sur- face in Chinese eyes with cataract and the related factors of spherical aberration for the choice of aspheric in- traocular lens. Methods Spherical aberration of anterior corneal surface, asphericity Q value and average corneal curvature was measured with an iTrace wavefront analyzer in 572 Chinese patients （572 eyes） with cataract. Axial length measured by IOLMaster was recorded for each eye. To analysis the relationship be- tween spherical aberration of anterior corneal surface and age, aspherieity Q value, average corneal curva- ture, corneal astigmatism, axial length. Results Mean value of spherical aberration was （ 0.25± 0.08 ） μm for the central 6 -mm zone. The spherical aberration was positively correlated with asphericity Q value, average corneal curvature and negatively correlated with axial length （ P 〈 0.05 ）. No statistically significant correlation was found between spherical aberration and age, astigmatism（ P 〉 0.05 ）. The influence of asphe- ricity Q value（ Beta = 0. 837, P 〈 0. 001 ） and average corneal curvature （ Beta = 0. 250, P 〈 0. 001 ） were statistically significant in spherical aberration. The data were divided into three groups according to aspherie- ity Q value（ G1 ： - 1 〈 Q 〈 0 ;G2 ： Q = 0 ; G3 ： Q 〉 0 ）. The difference in spherical aberration among three groups was statistically significant （P 〈 0.05 ）. Conclusion There is significant interindividual variabilityin corneal spherical aberration. Corneal spherical aberration is correlated with asphericity Q value, average corneal curvature positively and axial length negatively. The influence of asphericity Q value and average cor- neal curvature are statistically significant. Accurate measurement of spherical aberration is necessary for the individualized choice of aspherical intraocular lens.