角膜厚度的共焦显微镜测量分析

Corneal thickness measurement with confocal microscopy

目的 研究共焦显微镜测量角膜厚度的准确性和稳定性。方法 非随机性对照临床试验 ,用裂隙扫描共焦显微镜和 A超测厚仪分别测量 2 0人的 2 7个正常角膜中央厚度。结果 中央角膜厚度测量平均值 (± SD)裂隙扫描共焦显微镜为 (5 2 9.6± 33.9)μm ,A超测厚仪为 (5 36 .7± 38.2 )μm,两者差别有显著意义 (P <0 .0 0 1,配对资料 t检验 ) ,两方法差值所在范围 (± SD)是 (7.0± 7.1)μm ;各眼测量值间标准差的平均值共焦显微镜为 17.8μm ,A超测厚仪为 1.7μm ,共焦显微镜的变异度较 A超测厚仪大。结论 裂隙扫描共焦显微镜可以测量角膜厚度 ,但其测量值与 A超测厚仪所测值有差别 ,且测量变异度较 A超测厚仪大 ,稳定性相对差。

Objective To determine the accuracy and reproducibility of central corneal thickness(CCT) measurement with slit scanning confocal microscope. Methods In a prospective comparative clinical trial, 27 normal central corneas of 20 subjects were admitted for measurement of thickness with Confoscan 2.0 slit scanning confocal microscope (SSCM) and Sonomed ultrasound pachymeter(PACH).Result Central corneal thickness (±SD) of 27 corneas in 20 subjects measured by SSCM(529.6±33.9)μm and by PACH(536.7±38.2)μm differed (P<0.001,paired Student's t-test ),and the difference between both methods was over the range of CCT(mean difference , 7.0±7.1)μm .The mean intrapatient SD of SSCM was 17.8μm showed much greater than 1.7um of PACH, which indicated that SSCM had poorer reproducibility compared with PACH. Conclusion The SSCM is a poorer precise technique for measuring central corneal thickness than ultrasound pachymeter.