近视眼角膜高阶像差和屈光度及角膜曲率的相关性分析

Corneal high order aberrations in adults with myopia: correlations with myopic degree and keratometry

摘要:

目的：通过测量近视眼角膜高阶像差，探讨其与屈光度和角膜曲率等参数的相关性。

方法：选取单纯近视患者63例126眼，行眼科常规检查、角膜地形图及角膜波前像差检查。统一选取右眼，按等效球镜度分为中低度近视组(<-6.00D)和高度近视组(≥-6.00D)，比较两组患者的第三、四、五阶主要角膜高阶像差并分析其与屈光度、角膜曲率、眼内压、中央角膜厚度和年龄的相关性。用Kolmogorov-Smirnov Test进行数据的正态性分布检验，两样本间比较采用独立样本t检验，两连续变量间相关分析采用Pearson相关分析。

结果：中低度近视和高度近视组间四叶草像差(Z₄₄)有统计学差异(t=2.51，P=0.02)； 高度近视组眼内压与次级水平三叶草(Z_5-3)呈显著负相关(r=-0.52，P=0.01)，中央角膜厚度与四叶草像差(Z_4-4)呈显著正相关(r=0.43，P=0.03)； 中低度近视组角膜高阶像差参数与屈光度参数间无相关性(P>0.05)，高度近视组等效球镜度和球镜度与总彗差(TCA)呈负性相关(r=-0.57，P=0.002； r=-0.55，P=0.003)； 中低度近视组及高度近视组的平均角膜屈光力、陡峭角膜屈光力及平坦角膜屈光力与初级球差(Z₄₀)均有显著正性相关(中低度组：r=0.40，P=0.02； r=0.39，P=0.02； r=0.40，P=0.02； 高度组：r=0.55，P=0.03； r=0.51，P=0.01； r=0.57，P=0.01)，高度近视组次级倾斜三叶草(Z₅₃)与陡峭角膜屈光力呈显著负相关(r=-0.4，P=0.04)。

结论：近视眼角膜高阶像差的某些组成成分受屈光度和角膜曲率的影响，其中角膜球差受角膜曲率影响，呈显著正性相关，高度近视患者总彗差受球镜度和等效球镜度的影响，呈显著负性相关。

Abstract:

AIM: To investigate the corneal high order aberrations in adults with myopia and to study its correlations with myopic degree and keratometry.

METHODS: A total of 63 patients(126 eyes)from the ophthalmology department of our hospital were included in this study during May 2014 to June 2015. Visual acuity, intraocular pressure(IOP), diopter, slit lamp examination, central corneal thickness(CCT), funduscopic examination, corneal topography and corneal total higher order aberrations(THOAs)were recorded. Right eye was selected. According to the spherical equivalence(SE), 63 eyes were divided into two groups, the mild to moderate myopia group(M-M group, SE<-6.00D)and the high myopia group(H group, SE≥-6.00D). The correlations of corneal THOAs with diopter, keratometry, IOP and CCT were analyzed. Kolmogorov-Smirnov Test was used for normality test. Independent-samples t test was used for comparison between two groups. Pearson correlation analysis was for comparison between two continuous variables.

RESULTS: Z₄₄ was found a statistic difference between the M-M group and H group(t=2.51,P=0.02). IOP was negatively correlated with Z_5-3(r=-0.52,P=0.01), and CCT was positively correlated with Z_4-4(r=0.43,P=0.03)in H group. There was no correlation between higher order aberrations and SE in M-M group(all P>0.05)Total coma aberration(TCA)was negatively correlated with SE(r=-0.57,P=0.002)and spherical degree(Sph, r=-0.55,P=0.003)in H group. Z₄₀ was positively correlated with average K(AK)(M-M group:r=0.40,P=0.02. H group:r=0.55, P=0.03), K steep(K_s)(M-M group:r=0.39, P=0.02. H group:r=0.51, P=0.01)and K flat(K_f)(M-M group:r=0.40, P=0.02. H group:r=0.57, P=0.01)in both groups. Z₅₃ was negatively correlated with K_s (r=-0.4,P=0.04)in H group.

CONCLUSION: The THOAs parameters are influenced by diopter and keratometry. TCA is negatively correlated with SE and Sph in patients with high myopia, and spherical aberration is positively correlated with keratometry.