三种不同仪器测量角膜前表面曲率的研究

目的：研究电脑自动验光仪（Autorefractor）、光学相干生物测量仪（IOL-Master）、眼前节分析系统（Pentacam）三种仪器测量角膜前表面曲率有无差异，并对三种测量的结果进行一致性评价。方法分别采用三种仪器对51例（99只眼）测量角膜中央前表面3 mm的最陡峭径线（ Ks）及最平坦径线（ Kf）应用单因素方差分析、线性相关分析及Bland-Altman一致性分析等统计学分析方法，评价三种仪器测量结果的差异及一致性。结果电脑验光仪、IOL-Master及Pentacam 测量的Kf 值分别为（42．92±1．21）、（42．98±1．23）、（42．86±1．23）D，Ks值分别为（43．87±1．26）、（43．94±1．25）、（43．74±1．33）D。三种仪器间Kf、Ks值均无统计学差异（P值分别为0．898、0．714）。对于Kf、Ks任意两种仪器间的Pearson系数均大于0．9，显示了各仪器测量结果间显著的相关性。两两仪器间测量结果差值的平均值最大分别为0．12（Kf）、0．14（Ks）。分别对Kf和Ks进行两仪器间Bland-Altman分析，结果表明均有大于95％的数据点位于95％一致性区间内，且此区间窄，可被临床上接受。结论电脑自动验光仪、光学相干生物测量仪和眼前节分析系统三种仪器对角膜中央3 mm前表面曲率的测量无统计学差异，有显著的相关性及较好的一致性。

Measurements of anterior corneal power by using three different instruments

Objective To compare the measurements of anterior corneal power obtained by Autorefractor , IOLMaster and Pentacam . Methods The subjects of this study included 51 healthy cases （99 eyes）.Anterior corneal power was measured respectively by using Autorefractor （Accuref-K 9001,Shin-Nippon,Japan）,IOL-Master （CarlZeiss,Germany） and Pentacam （Oculus,Germany）.The flat corneal power （Kf） and steep corneal power （Ks） were measured by three instruments.All data were analyzed using ANOVA analysis and correlation analysis .Bland-Altman method was used to evaluate the agreement of three instruments .Results The Kf values of Au-torefractor,IOL-Master,and Pentacam were（42.92 ±1.21）,（42.98 ±1.23）and（42.86 ±1.23） D,respectively.The Ks values of Au-torefractor,IOL-Master and Pentacam were（43.87 ±1.26）,（43.94 ±1.25）and（43.74 ±1.33） D,respectively.There were no significant differences in Kf and Ks among three instruments .Pearson＆#39;s correlation coefficients between any two kinds of instruments were higher than 0.9 for Kf and Ks.The results suggested significant correlations among the measurements of the three instrument .The max mean differences of Kf and Ks between the two instruments were 0.12 and 0.14.Bland-altman analysis of Kf and Ks between the two instruments showed that more than 95%data points were located in the 95%limits of agreement .The limits were narrow and accepta-ble.Conclusions The results of autorefractor ,IOL-Master and Pentacam showed no statistical differences ,but a significant correlation and agreement .