国人近视屈光手术人群Q值的相关因素分析

目的探讨我国近视屈光手术人群的角膜前表面非球性参数（Q值）的分布及其相关因素。方法随机选择18～44岁行近视分子激光角膜屈光手术者120例（240眼）。按屈光度分为低、中、高度3组，各组均为40例（80眼）。应用AstraMax二三维角膜综合检查站行角膜地彤网检查，记录角膜曲率及Q值；并行综合验光、角膜中央厚度、眼轴长度及其他常规术前检查。分别将Q值与各参数进行统计学分析。结果总体Q值均数为-0．16±0．17，呈正态分布；Q〈0者206眼，占85．83％；Q值与性别、眼别间差异无统计学意义；Q值与屈光度之间存在线性相关关系（F=9．6665，P〈0．05），高度近视组和低度、中度组问的差异有统计学意义（q=4．0037，P〈0．05；q=3．1218，P〈0．05）；低中度近视组问差异无统计学意义。Q值与角膜中央厚度、平均角膜曲率、眼轴长度呈无相关性。结论我国近视屈光手术人群的Q值呈正态分布，大部分人群角膜为长椭圆形（prolate）。Q值与屈光不正程度相关，而与性别、角膜中央厚度、平均角膜曲率、眼轴长度之间无相关性。

Analyse of Q value and its related parameters in Chinese myopia population for corneal laser refractive surgery

Objective To investigate the distribution features of Q value of corneal anterior surfaee in Chinese myopia population for refractive surgery, and analyse the relationship between Q value and other related parameters. Methods 120 myopic patients （240 eyes） for laser-assisted in situ keratomileusis （LASIK） were randomly dividied into three groups with the degree of refractive error （40 cases （80 yees） in each group of high diopter, middle diopter and low dioper） . Each subject received investigations as follows： corneal topography （Q value and corneal curvature ）, subject refraction, central corneal thickness, ocular axis and other routine pre-surgery exams. The correlation between Q value and other parameters were analyzed. Results Average Q value was （ -0. 16 ±0. 17） and became Gauss distribution. 206 eyes （ Q 〈 O） was 85. 83%. There were no statistically significant difference in Q value and different eye or different sex. Q value showed linear correlation with diopter of refractive error（ F = 9. 6665, P 〈 0. 05 ）. There were statistically significant difference between high diopter group and other groups in Q value （q= 4. 0037, P〈0. 05; q= 3. 1218,P 〈0. 05）. There were no statistically significant differ- ence in low group and middle groups（q =0. 8818, P 〉0. 05）. There were no correlation found between Q value and corneal thick- ness ,corneal curvature or ocular axis （ F = 2. 6877,P 〉 0. 05 ; F =1.6407, P〉0. 05; F= 0. 7176,P〉0.05）. Conclusion In Chinese myopic population for refractive surgery, Q value were Gauss distribution and corneal curvature of majority population become prolate. Correlations existed between Q value and the degree of refractive error, but not between Q value and sex, central corneal thickness , corneal curvature or ocular axis.