Pentacam与IOL Master测量角膜曲率与散光的比较

Comparison of keratometry and astigmatism measured by Pentacam and IOL Master

目的：比较Pentacam与IOL Master测量年龄相关性白内障患者角膜曲率、角膜散光的差异。方法选取2013年7至10月在惠州市中心人民医院接受手术治疗的年龄相关性白内障患者109例（共171眼），对入选患者由同一检查者检查，各收集3组数据并取其均值为对应测量值。角膜曲率的差异性、相关性、一致性分别采用配对样本t检验、线性相关分析、Bland-Altman法进行分析。角膜散光的比较采用Wilcoxon符号秩检验及简单统计。结果 Pentacam所测平均角膜曲率为男（44.14±1.49）D、女（44.73±1.55）D，IOL Master为男（44.27±1.50）D、女（44.86±1.56）D，不同仪器、性别间差异均有统计学意义（均P〈0.05）。经Pearson检验二者间有显著相关性（r=0.986）。Bland-Altman散点图中，95%一致性界限范围内两者间最大差值的绝对值为1.19 D。Pentacam与IOL Master所测散光度数、轴位分别为（0.77±0.52）D、（85.38±53.36）°与（0.90±0.61）D、（91.35±53.60）°，二者在散光度数上差异有统计学意义，在轴位上差异无统计学意义，但轴位差在10°以上者占44.4%。结论 Pentacam与IOL Master两种仪器均可较准确地测量白内障患者的角膜曲率与角膜散光，二者间相关性好，一致性差。

Objective To compare the difference of keratometry and astigmatism measured by Pentacam and IOL Master in age-related cataract operations. Methods The inspection of involved patients was taken by the same operator.The data of keratometry and corneal astigmatism were the average of three sets. Paired t tests ,A simple linear correlation analysis and the Bland-Altman method were used to evaluate the difference, correlation and agreement of keratometry respectively. Wilcoxon signed rank test and simple statistical analysis were performed to compare the difference of corneal astigmatism. Results The mean keratometry value were （44.14±1.49） D （male）, （44.73±1.55） D （female） for Pentacam,and （44.27±1.50） D （male）、（44.86±1.56） D （female） for IOL Master. There was significant statistical difference in keratometry value both in the terms of instrument and sex.The correlation of keratometry was high（r=0.986）. The absolute value of the maximum difference was 1.19 D in the 95%limits of agreement of Bland-Altman histogram. The astigmatism degree and axis were （0.77±0.52） D and （85.38 ±53.36）° for Pentacam, （0.90±0.61） D and （85.38 ±53.36）° for IOL Master.There was obivous statistical difference in astigmatism degree between the two instruments, while, no great difference in axis.The percent of astigmatism axis difference above 10° was 44.4%. Conclusions Both Pentacam and IOL Master can measure corneal curvature and astigmatism of cataract patients accurately.There are good correlation and poor consistency.