Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Republic of Korea.
Ophthalmology. 2010 Nov;117(11):2096-103. doi: 10.1016/j.ophtha.2010.03.002. Epub 2010 Jun 16.
To compare the reliability and the agreement in measuring central corneal thickness (CCT) using the following technologies: RTVue Fourier-domain optical coherence tomography (Optovue, Inc., Fremont, CA), Pentacam (Oculus, Inc., Wetzlar, Germany), and ultrasonic pachymetry (USP; Pocket-II; Quantel Medical, Inc., Bozeman, MT).
Evaluation of diagnostic test.
One hundred four eyes of 52 healthy subjects (mean age ± standard deviation, 28.6 ± 4.8 years).
One eye from each subject was assigned randomly for a repeatability test in which a single operator performed 3 successive measurements. The other eye underwent an interoperator reproducibility test by 3 operators. Two centering methods of RTVue and 3 types of CCT from Pentacam were investigated. For USP, 1 drop of topical anesthetic was administered, and measurement was initiated 90 seconds later. Agreement among the instruments was evaluated using Bland-Altman plots.
Various types of CCT were compared: central zone average and minimum thickness of RTVue centering on the vertex and the pupil; corneal thickness at the pupil center, apex, and thinnest location from Pentacam; and mean CCT of 5 repeated measurements of USP. The reliability of measurement was assessed using the repeatability or reproducibility coefficient (Rco), the coefficient of variation, and the intraclass correlation coefficient. The limit of agreement was used to analyze concordance.
The Rco of RTVue was 4 to 5 μm, which was comparable with that of USP and better than that of Pentacam (10-11 μm). The Rco was not dependent on centering methods (RTVue) or types of CCT (Pentacam). The location of minimum thickness found by RTVue was less reliable than that of the Pentacam. The central zone average of RTVue was approximately 7 μm larger than the pupil center or apex thickness of Pentacam and approximately 13 μm larger than the CCT measurement of USP. Those discrepancies could be as high as 20 and 23 μm, respectively. The minimum thickness measured by the RTVue was similar to that of Pentacam.
The RTVue is a rapid and reliable noncontact means of measuring CCT; however, the characteristics of CCT measured by RTVue must be understood when comparing the CCT obtained by the Pentacam or USP.
FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
比较以下技术测量中央角膜厚度（CCT）的可靠性和一致性：RTVue 傅里叶域光学相干断层扫描仪（Optovue，Inc.，弗里蒙特，加利福尼亚州），Pentacam（Oculus，Inc.，威茨拉尔，德国）和超声角膜测厚仪（USP；Pocket-II；Quantel Medical，Inc.，博兹曼，MT）。
诊断测试评估。
52 名健康受试者的 104 只眼（平均年龄±标准差，28.6±4.8 岁）。
每位受试者的一只眼睛随机进行重复性测试，由一名操作员进行 3 次连续测量。另一只眼睛由 3 名操作员进行操作员间可重复性测试。研究了 RTVue 的 2 种定心方法和 Pentacam 的 3 种 CCT 类型。对于 USP，给予 1 滴局部麻醉剂，90 秒后开始测量。使用 Bland-Altman 图评估仪器之间的一致性。
比较了各种 CCT：RTVue 以顶点和瞳孔为中心的中央区平均和最小厚度；Pentacam 瞳孔中心、顶点和最薄位置的角膜厚度；以及 USP 5 次重复测量的平均 CCT。使用重复性或再现性系数（Rco）、变异系数和组内相关系数评估测量的可靠性。使用界限协议分析一致性。
RTVue 的 Rco 为 4 至 5μm，与 USP 相当，优于 Pentacam（10-11μm）。Rco不依赖于定心方法（RTVue）或 CCT 类型（Pentacam）。RTVue 发现的最小厚度位置不如 Pentacam 可靠。RTVue 的中央区平均厚度比 Pentacam 的瞳孔中心或顶点厚度大约大 7μm，比 USP 的 CCT 测量值大约大 13μm。这些差异可能分别高达 20μm 和 23μm。RTVue 测量的最小厚度与 Pentacam 相似。
RTVue 是一种快速可靠的非接触式 CCT 测量方法；然而，在比较 Pentacam 或 USP 获得的 CCT 时，必须了解 RTVue 测量的 CCT 特征。
作者没有与本文讨论的任何材料有关的专有或商业利益。
