OrbscanⅡ角膜地形图仪和A型超声角膜测厚仪测量LASIK手术前后角膜厚度的比较

Measurements of corneal thickness with the OrbscanⅡ Topography System and with A-ultrasonic pachymeter

目的比较OrbscanⅡ角膜地形图仪和角膜测厚仪(A超)检测角膜厚度的差异。方法分别用Orb-scanⅡ角膜地形图及A超对角膜厚度进行检测,并将测量值进行统计学分析。结果OrbscanⅡ测得术前角膜厚度为(524.97±41.41)μm,A超测得角膜厚度为(528.57±33.04)μm。OrbscanⅡ测量值与A超测量值差异有统计学意义(t=-5.093,P<0.001),两种测厚结果高度正相关(r=0.915,P<0.001),回归方程如下:A超测量值(μm)=158.840+[0.702×OrbscanⅡ测量值(μm)]。通过检验,两种测厚方法对术后角膜厚度的测量结果符合术前的回归方程。结论OrbscanⅡ和A超检测中央角膜厚度显示了高度的相关性;二者结合使用可以为LASIK手术患者提供准确的角膜厚度值,并可从总体上了解角膜的形态,可以准确地评估屈光手术前后角膜的参数,并有效保证手术的安全性。

Objective To compare the difference measurements of corneal thickness with the Orbsean Ⅱ Topography system and with A-ultrasonic pachymeter. Methods To measure 967 eyes of 490 myopia patients with the Orbscan Ⅱ Topography System and A-ultrasonics respectively. Then compare the result of corneal thickness. Results The mean center corneal thickness was （524.97 ± 41.41 ）μm with the Orbscan Ⅱ System and （528.57 ± 33.04 ）μm with the A-ultrasonics,these values being signifieandy diferent（ t = -5. 093, P 〈 0.01 ）. There were significant linear correlations between Orbscan Ⅱ and A-ultrasonic（ r =0.915, P 〈0.001 ）. The regression equation was ：Y（ A-ultra sonic, μm） = 158. 840 ＋ [. 702 x X （ Orbscan Ⅱ, μm ） ]. Conclusion There was a significant correlation between the results otained by both techniques. Contrary to the ultrasonic pachymeters the Orbsean simultaneously measures several thousand points including the thinnest point and provides a colour-coded thickness map without physical contact.