三种仪器测量LASEK术后中央角膜厚度的比较

Comparison of central corneal thickness measurements after LASEK by three instruments

目的:比较光学相干断层扫描(optical coherence tomography,OCT)、角膜内皮计与超声测厚仪测量准分子激光上皮下角膜磨镶术(laser subepithelial keratomileusis,LASEK)术后患者中央角膜厚度(CCT)的差异性和相关性。方法:选取LASEK术后6mo复诊的近视患者49例96眼,对每位患者分别用OCT、角膜内皮计、超声测厚仪三种仪器测量其CCT,数据统计分析采用配对t检验和Pearson相关性分析。结果:OCT、角膜内皮计、超声测厚仪测量CCT的平均值为分别为475.15±33.67,447.80±34.11,465.18±34.23μm。手术预留CCT平均值为431.22±35.32μm。三种仪器所测量结果之间两两比较差异均有统计学意义(P<0.05)。线性相关显示超声测厚仪与OCT、角膜内皮计两种仪器之间存在正相关(r=0.949,0.983,P<0.01)。LASEK术后实际CCT较手术预留角膜厚度要厚。结论:三种仪器的中央角膜厚度测量值不可互换。

AIM： To compare the differences and the relationships of central corneal thickness （ CCT） measurements among optical coherence tomography （ OCT ） , Tomey pachymetry and ultrasound pachymetry after laser assisted subepithelial keratomileusis （ LASEK） . METHODS：Forty-nine patients （ 96 eyes ） with myopia after 6mo of LASEK were assigned to measure the CCT by OCT, Tomey pachymetry and ultrasound pachymetry. Paired t-test and Pearson correlation analysis was used for statistical analysis. RESULTS： The mean CCT measured by OCT, Tomey pachymetry and ultrasound pachymetry was （ 475.15 ± 33.67μm）, （447.80 ±34.11μm）, （465.18 ±34.23μm）, respectively.Surgery reserved mean CCT was （ 431.22 ± 35.32 ）μm.There were statistically differences between two comparative measured results （P＆lt;0.05）.Ultrasound pachymetry had a positive correlation with OCT and Tomey pachymetry （ P ＆lt;0.01 ）, and the correlation coefficient was 0.949 and 0.983, respectively.The actual CCT of 6mo post-operation was thicker than surgery reserved CCT. CONCLUSION： The CCT measurements of three instruments were not interchangeable.