Sirius Orbscan-Ⅱ及超声测厚仪三种仪器测量中央角膜厚度的比较

Comparison among 3 methods to measure central corneal thickness： Sirius, Orbscan-II and Ultrasound Pachymetry

目的评估Sirius、OrbscanII技趟声测厚仪测量中央角膜厚度（CCT）的差异和一致性．方法对250例（500只眼）近视眼患者，依次采用Sirius、OrbscanII及USPiN量CCT。结果sm—US、OrbscanII及USP测得的平均ccT分别为（525．7＋36．7）um、（515．5＋44．1）μm、（529．1＋35．8）um：3种仪器测f扣CCT高度相火：Sirius与USP（r=0．964，P〈0．001）、OrbscanII与USP（r=O．932．P〈0．001）、Sirius与OrbscanⅡ（r=0．940，P〈0．001）。CCT的差值均数（包括一致性界限的上线和F线）为Sirius’-JUSP（3．4＋9．8）Ixm、（-15．7，22．6）、OrbscanⅡ’jUSP（13．6±16．9）μm（-19．4，46．7）、Sirius与OrbscanII（10．2＋15．8）μm（-20．8，41．2）结论与USP棚比，Sirius与OrbscanⅡ低估了中央角膜厚度。与OrbscauⅡ相比，Sirius与USP有较好的相关性和一致性？3种仪器测量CCT不可q：卡II替换：Sirius可能逐渐取代角膜厚度测量的金标准。

Objective To assess the difference and agreement of central corneal thickness mea- surements between Sirius, Orbscan II, and ultrasound pachymetry （USP）. Methods On 250 myopic patients （500 eyes）, the central corneal thickness was measured using Sirius, Orbscan II and ultra- sound pachymetry in turn. Results The mean measurements of average central corneal thickness by Sirius, Orbscan I1, and USP were 525.7±36.71am, 515.5±44.1gm and 529.1±35.8μm respectively. There was high correlation between the three instruments： Sirius with USP （r =0.964, P 〈0.001）, Orb- scan II with USP （r =0.932, P 〈0.001） and Sirius with Orbscan lI （r =0.940, P 〈0.001）. The mean differences （and upper/lower LOA） for central corneal thickness measurements were 3.4±9.8gm （-15.7, 22.6） between Sirius and USP, 13.6±16.9gm （-19.4,46.7） between Orbscan II and USP, and 10.2± 15.8gm （-20.8,41.2） between Sirius and Orbscan Ⅱ. Conclusions Sirius and Orbscan II underesti- mate corneal thickness compared with that measured with USR Sirius has better correlation and agreement with the gold standard USP, as compared with Orbscan II. The three instruments can not be used interchangeably for measuring central corneal thickness. Sirius eventually may replace USP as the gold standard for corneal pachymetry.