RTVue傅立叶OCT与超声角膜测厚仪测量LASIK术前角膜厚度的对比研究

 目的 探讨RTVue傅立叶域光学相干断层成像系统(fourier domain optical coherence tomography,FD-OCT)与超声角膜测厚仪(ultrasonic pachymeter,USP)测量LASIK术前患者中央角膜厚度(corneal central thickness,CCT)的差异和可重复性.方法 选取近视患者800例(1600眼),分别应用RTVue-OCT和USP进行CCT测量.按等值球镜屈光度和USP测得角膜厚度不同各分4组,比较两种仪器测量值的差异和相关性.随机选择60例(60眼)用两种仪器依次重复测量CCT3次,对两种仪器重复测量值的标准差均值进行配对t检验.结果 RTVue-OCT和USP测得的CCT平均值分别为(528.47±29.84)μm和(537.89±30.56)μm,差异有统计学意义(P<0.01).OCT与USP测量值呈线性正相关(r=0.921,P<0.001),二者的相关公式为OCT测量值=2.2492×USP测量值0.8678.OCT和USP的CCT重复测量的标准差平均为3.87和6.38,差异有统计学意义(P<0.01).结论 RTVue傅立叶OCT的测厚功能与超声测量具有良好一致性,可重复性好,故可作为角膜厚度测量的工具之一,并可作为LASIK术前、术后综合分析观察的方法.

A comparison of corneal thicknesses measured before LASIK by RTVue FD-OCT system and ultrasonic pachymetry

Objective To study the dissimilarity and repeatability of the measurement of corneal central thickness （CCT） applied to LASIK preoperative patients between RTVue fourier domain optical coherence tomography （ RTVue FD - OCT） and ultrasonic pachymeter （USP）. Methods CCT was measured by RTVue FD - OCT and USP separately in 800 myopic preoperative patients （ 1600 eyes）. The eyes were divided into four groups according to the difference in cornea thickness measured by spherical equivalent refraction and USP. These two results of measurement were compared for their difference and correlation. Sixty samples （60 eyes） were selected randomly. The CCT was measured three times using RTVue FD - OCT and USP separately. Results The mean value of RT- Vue FD- OCT and USP was （528.47 ± 29.84） μm and （537.89 ± 30.56） μm, respectively; the difference was statistically significant（ P 〈 0.01 ）. RTVue and USP were in linear correlation （ r = 0.921 ,P 〈 0.01 ） Their relevant formula was： the measurement val- ue of OCT = 2. 2492 x USP measurement value 0. 8678. The mean standard deviations of repeated CCT measurement value of OCT and USP were 3.87 and 6.38 respectively, The discrepancy of standard deviation between RTVue and USP was of statistical significance （ P 〈 0.01 ）. Conclusions RTVue FD - OCT is as efficient in measuring the corneal thickness as ultrasound. Thus, it can be used as a tool for pachymetry and a method for meta - analysis and observation before and after LASIK.