Vissum Corporation-Instituto Oftalmológico de Alicante, Universidad de Alicante, Alicante, Spain.
J Cataract Refract Surg. 2011 Feb;37(2):310-6. doi: 10.1016/j.jcrs.2010.08.038.
To evaluate the intraobserver repeatability of pachymetric measurements obtained with a new Scheimpflug photography-based system and the agreement of the measurements with those obtained by optical coherence tomography (OCT).
Vissum Corporation, Alicante, Spain.
Evaluation of diagnostic technology.
Corneal thickness was measured at different locations (center; 2.5 mm and 4.0 mm nasal, temporal, superior, and inferior) in 18 eyes of 18 patients with no ocular pathology or previous surgery with a Scheimpflug photography-based system (Sirius). Three consecutive measurements at each location were obtained with the system to evaluate intraobserver repeatability. Afterward, pachymetric measurements were obtained at the same locations with an OCT system (Visante) to evaluate the agreement between techniques using the Bland-Altman method.
The intraclass correlation coefficient of repeated measures ranged from 0.990 to 0.997. The coefficient of variation was lower than 1% and the standard deviations of the repeated measurements (S(w)) were below 6 μm at all corneal locations. Statistically significant differences were found between the coefficient of variation and S(w) values of the repeated measurements corresponding to the 2.5 mm and 4.0 mm locations (P ≤ .037). The agreement with OCT pachymetric measurements was poor, with ranges of agreement larger than 20 μm at all corneal locations. Statistically significant differences were found between standard deviations of the differences between the 2 devices at the 2.5 mm and 4.0 mm locations (P ≤ .017).
Scheimpflug photography-based technology provided repeatable pachymetric measurements that were not equivalent to those obtained with OCT.
评估一种新型基于 Scheimpflug 摄影的系统获取的角膜厚度测量值的观察者内重复性，以及与光学相干断层扫描（OCT）测量值的一致性。
Vissum 公司，阿利坎特，西班牙。
诊断技术评估。
对 18 例无眼部病理或既往手术史的患者的 18 只眼的不同部位（中央；2.5mm 和 4.0mm 鼻侧、颞侧、上侧和下侧）进行角膜厚度测量，使用基于 Scheimpflug 摄影的系统（Sirius）获得每个部位的 3 次连续测量值，以评估观察者内重复性。然后，使用 OCT 系统（Visante）在相同部位获取角膜厚度测量值，使用 Bland-Altman 方法评估两种技术之间的一致性。
重复测量的组内相关系数范围为 0.990 至 0.997。变异系数低于 1%，所有角膜位置的重复测量标准差（S(w)）均低于 6μm。在 2.5mm 和 4.0mm 位置，重复测量的变异系数和 S(w)值之间存在统计学显著差异（P≤0.037）。与 OCT 角膜厚度测量值的一致性较差，所有角膜位置的一致性范围均大于 20μm。在 2.5mm 和 4.0mm 位置，两种设备之间差异的标准差存在统计学显著差异（P≤0.017）。
基于 Scheimpflug 摄影的技术提供了可重复的角膜厚度测量值，但与 OCT 测量值不一致。
