目的：利用Lenstar LS900，OrbscanⅡ系统及A超角膜测厚仪测量近视眼患者中央角膜厚度(central corneal thickness，CCT)，探讨三种测量方法的差异，并对结果进行相关性和一致性评价，为临床应用提供理论依据。

方法：随机选取角膜屈光手术术前近视眼患者35例70眼分别用Lenstar LS900，OrbscanⅡ及A超角膜测厚仪依次重复测量CCT 3次，取其平均值进行统计学分析。不同方法测量CCT之间采用随机区组方差分析，组内两两比较采用LSD-t检验，三种测量方法之间的相关性采用直线相关分析，一致性检验采用Bland-Altman分析。以P<0.05为差异有统计学意义。

结果：Lenstar LS900，OrbscanⅡ及A超角膜测厚仪测得的近视眼患者CCT均数分别为542.75±40.06，528.74±39.59，538.54±40.93μm。Lenstar LS900的测量值较A超角膜测厚仪的测量值大4.21±8.78μm，较OrbscanⅡ测量值大14.01±13.39μm，OrbscanⅡ测量值较A超角膜测厚仪小9.8±10.57μm，差异均有统计学意义(P<0.05)。3种不同仪器测量结果均具有显著相关性，Lenstar LS900和A超角膜测厚仪、OrbscanⅡ测量值呈正相关：r=0.977(P<0.05)，r=0.944(P<0.05)。Bland-Altman方法分析：Lenstar LS900和A超角膜测厚仪95%一致性区间上下值为-13.0～21.4μm，1.4%的点在95%的一致性界限以外，OrbscanⅡ与A超角膜测厚仪95%一致性区间上下值为-30.5～10.9μm ，7.1%的点在95%一致性界限以外，Lenstar LS900和A超角膜测厚仪一致性更好。

结论：LS900与A超角膜测厚仪和Orbscan Ⅱ系统测量CCT一致性及相关性好，Lenstar LS900可以作为近视患者CCT的非接触式测量工具。

AIM: To investigate the difference of central corneal thickness(CCT)measured by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry, and to evaluate the correlation and consistency of the results for providing a theoretical basis for clinical application.

METHODS: The mean value of CCT in 70 eyes of 35 patients measured three times by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry underwent statistical analysis. The difference of CCT was compared, and the correlation and consistency of three measurements were analyzed to provide theoretical basis for clinical application. CCT values measured by different methods were analyzed with randomized block variance analysis. LSD-t test was used for pairwise comparison between groups. The correlation of three measurement methods were analyzed by linear correlation analysis, and Bland-Altman was used to analyze the consistency.

RESULTS: The mean CCT values measured by Lenstar LS900, OrbscanⅡ and ultrasonic pachmetry were 542.75±40.06, 528.74±39.59, 538.54±40.93μm, respectively. The mean difference of CCT measurement was 4.21±8.78μm between Lenstar LS900 and ultrasonic pachmetry, 14.01±13.39μm between Lenstar LS900 and Orbscan Ⅱ, 9.8±10.57μm between ultrasonic pachmetry and Orbscan Ⅱ. The difference was statistically significant(P<0.05). Three measurements were highly correlated(P>0.05): There was positive correlation between CCT with Lenstar LS900 and ultrasonic pachmetry(r=0.977, 0.944; P<0.05). The analysis method of Bland-Altman: 95% consistent interval of upper and lower value was -13.0～21.4μm between Lenstar LS900 and ultrasonic pachmetry, 1.4% points outside the limits of agreement of 95%, 95% consistent interval of upper and lower value was -30.5～10.9μm between OrbscanⅡ and ultrasonic pachmetry, 7.1% points outside the limits of agreement of 95% consistent interval.

CONCLUSION: There are excellent correlation among Lenstar LS900, Orbscan Ⅱ and ultrasonic pachmetry. Lenstar LS900 can be used as CCT non-contact measurement tool.