OrbscanⅡ系统与A超角膜测厚仪测量近视眼角膜中央厚度的比较

Comparison of central corneal thicknesses measured by Orbscan Ⅱ system and Ultrasonic pachymetry in myopia

目的将orbscanⅡ系统与A超角膜测厚仪测量的近视眼中央角膜厚度的结果，进行对比分析，为临床手术提供准确的数据。方法选取近视患者200例（400只眼），按屈光度、A超测得角膜厚度不同分成4组。分别应用OrbscanⅡ系统及A超角膜测厚仪对角膜中央厚度进行测量。结果OrbscanⅡ系统与A超角膜测厚仪测得角膜中央厚度分别为（568．06±34．29）／μm和（536．25±33．90）μm，两者测量结果存在差异（P〈0．01）。OrbscanⅡ系统测量结果较A超角膜测厚仪结果厚（31．81±16．39）μm。按屈光度不同分组，即低度数组-0．50- -3．00D，中度数组-3．25～-6．00D，高度数组-6．25- -9．00D，超高度数组-9．25～-15．00D，OrbseanⅡ系统与A超角膜测厚仪两者之间差异显著（P〈0．01）。按A超测得角膜厚度分为4组，即I组≤500μm，Ⅱ组500～536μm，Ⅲ组536—572μm，Ⅳ组≥572μm。OrbscanⅡ系统与A超角膜测厚仪两者之间差异显著（P〈0．01）。结论OrbscanⅡ系统中央角膜厚度测量值比A超角膜测厚仪测量值厚约30μm，OrbscanⅡ系统不能完全替代A超角膜测厚仪。

Objective To evaluate the corneal thinknesses measured with Orbscan Ⅱ system and A - ultrasonic pachymetry. Two hundred myopic subjects（400eyes） were recruited and divided into four groups according to the diopter and corneal thickness measttred by A- ultrasonic pachymetry. Central corneal thicknesses （CCT） were measured with Orbscan Ⅱ topography system and A - ultrasonic pachymetry.Results The mean CCTby Orbscan Ⅱ system and A- ultrasonic pachymetrywere （568.06±34.29） μm and （536.25±33.90）μm respertively.The result of Orbscan Ⅱ system was higher than that of A- ultrasonic pachymetry with a difference of （31.81 ± 16.39） μm （ P 〈 0.01 ）. Firstly, The subjects were divided into four groups according to diopter： low myopia（ -0.50 - - 3.00D ）, medium myopia（ - 3.25- - 6.00D） ,high myopia（ - 6.25 - - 9.00D）and supermyopia（ - 9.25 - - 15.00D）, The results of Orbscan Ⅱ system were higher than those of A - ultrasonic pachymetry respectively（ P 〈 0.01 ）. Secondly, The subjects were divided into four groups based on the CCT measured by A - ultrasonic pachymetry ： group1（ ≤ 500 μm）, group 2 （500- 536 μm）, group 3 （536 - 572μm）, and group 4（ ≥ 572 μm）. The results of Orbscan Ⅱ system were higher than those of A - ultrasonic pachymetry （ P 〈 0.01 ）. Conclusions There were significant differencees between the results of these two apparatus. The outcomes of Orbscan Ⅱ system are approximately 30μm higher than those of A- ultrasonic pachymetry. Orbscan Ⅱ system cannot totally replace A - ultrasonic pachymetry.