超声角膜测厚仪和Orbscan测量LASIK术后角膜厚度的比较

A comparison of ultrasound and Orbscan measuring corneal thickness after LASIK

目的 比较不同的方法测量LASIK术后角膜厚度的差异及其相关性。方法 分别用美国DGH 40 0 0型超声角膜测厚仪和Orbscan Ⅰ眼前节系统测量LASIK术后 3个月以上的患眼角膜厚度 ,各测量 3次 ,取其平均值并进行比较。结果 超声角膜测厚仪测量值平均为 (4 4 5 66± 3 2 16) μm ,Orbscan测量值平均为 (3 95 5 0± 3 8 5 0 ) μm ,两者相差(5 0 17± 15 2 7) μm ,在统计学上有显著性差异 (P <0 0 1)。将两种方法测量结果作相关性分析 (r =0 92 2 ,P <0 0 1) ,呈显著正相关。回归方程如下 :超声角膜测厚仪测量值 (μm ) =14 1 0 3 3 1+ [0 770 2×Orbscan测量值 (μm ) ]。 讨论 Orbscan的软件设计是引起两种检测方法差异的主要原因之一 ,LASIK术后角膜的改变也可影响测量结果。对于外伤性角膜疾病及屈光手术后角膜厚度的测量 。

ObjectiveTo compare corneal thickness values after LASIK with ultrasonic and Orbscan system.MethodsCorneal thickness values after LASIK 3 months were measured using DGH 4000 ultrasonic corneal thickness measurement system and Orbscan Ⅰanterior system.ResultsCorneas measured by ultrasonic pachymetry (445 66±32 16)μm were thicker than that obtained by Orbscan (395 50±38 50)μm.There was a significant difference and a positive correlation between the two methods( P <0 01, r =0 922 P <0 01). ConclusionThe design of Orbscan is one of the main factors causing the difference between the two methods. The changes of cornea after LASIK also affect the result. A comparative analysis of the two values can offer reference for those cases which had traumatic corneal diseases or received refractive surgery.