3种仪器测量中央角膜厚度的比较研究

目的比较Pentacam、SP 3000和A型超声测量正常人中央角膜厚度的差异性及一致性。方法分别用Pentacam、SP 3000和A型超声测量40例正常人右眼的中央角膜厚度。结果 Pentacam、SP 3000和A超测量的中央角膜厚度分别为(535.8±33.8)μm、(508.6±35.5)μm和(530.7±36.9)μm;A型超声与Pentacam测量的中央角膜厚度无显著性差异(P=0.517),两者的差值为(5.4±7.9)μm,两者95%的一致性区间为(-18.1～7.8)μm;A型超声与SP3000测量的中央角膜厚度有显著性差异(P=0.006),两者的差值为(21.2±7.9)μm,95%一致性区间为(8.6～35.7)μm;SP 3000与Pentacam测量结果有显著性差异(P=0.001),两者的差值为(27.3±7.9)μm,两者95%的一致性区间为(13.7～40.8)μm。结论 Pentacam与A型超声测量正常人中央角膜厚度的差值较小,一致性较好,在测量正常人中央角膜厚度时可以相互替代使用;Pentacam与SP 3000、A型超声与SP 3000测量中央角膜厚度的一致性较差,在临床应用中要引起注意。

Comparison of central corneal thickness measurements by three different instruments

Objective It is to compare the difference and agreement in central corneal thickness measurements by Pentacam,SP 3000 and A-scan.Methods Totally 40 eyes of 40 volunteers were measured with Pentacam,SP 3000 and A-scan in central corneal thickness.Results The measurements of central corneal thickness were(535.8±33.8)μm,(508.6±35.5) μm and(530.7±36.9)μm respectively with Pentacam,SP 3000 and A-sca.The difference between Pentacam and A-scan was(5.4±7.9)μm,no statistically significant difference could be found(P=0.517),the 95% limit of agreement was(-18.1～7.8)μm.There was statistically significant difference between SP 3000 and A-scan measurements(mean difference was(21.2±7.9)μm,P=0.006),the 95% limit of agreement was(8.6～35.7)μm.There was statistically significant difference between SP 3000 and A-scan measurements(mean difference was(27.3±7.9)μm,P=0.001),the 95% limit of agreement was(13.7～40.8)μm.Conclusion Little difference and good agreement can be found between Pentacam and A-scan in central corneal thickness measurements.They can be used interchangeably in central corneal thickness of normal people.The agreement between Pentacam and SP 3000,A-scan and SP 3000 are bad.Attention should be paid to the differences between each two in the measurements of central corneal thickness.