Department of Internal Medicine, Division of Endocrinology and Metabolism, The Catholic University of Korea, Seoul, Korea.
AJR Am J Roentgenol. 2012 Apr;198(4):896-901. doi: 10.2214/AJR.11.7009.
The objective of this study was to evaluate interobserver agreement and intraobserver reproducibility in thyroid ultrasound elastography.
Fifty-six patients (56 nodules) were enrolled for this prospective study between December 2010 and March 2011. All patients were scheduled for thyroid surgery because their nodules had been found by fine-needle aspiration biopsies to be malignant, suspicious for malignancy, or follicular/Hürthle cell neoplasm. On each patient, three endocrinologists performed ultrasound elastography examinations using a commercial ultrasound machine. No external compression with the transducer was applied because pulsation from the carotid artery was used. Each endocrinologist repeated an elastography examination on the same thyroid nodule. An elasticity contrast index, which quantifies the local strain contrast within a nodule, was interactively determined after a nodule's boundary was delineated by the endocrinologist. A large elasticity contrast index value indicates an increased probability of the nodule being malignant. Pearson correlation coefficient was used to evaluate the interobserver and intraobserver agreement in the measured elasticity contrast index values, and p values < 0.05 were considered statistically significant.
Significant interobserver and intraobserver agreement was found in thyroid ultrasound elastography. Pearson correlation coefficients between two observers were 0.79 (observers 1 and 2, p < 0.01), 0.77 (observers 1 and 3, p < 0.01), and 0.73 (observers 2 and 3, p < 0.01). Pearson correlation coefficients for intraobserver agreement were 0.87 (p < 0.01), 0.73 (p < 0.01), and 0.84 (p < 0.01) for observers 1, 2 and 3, respectively.
Good interobserver and intraobserver agreement exists in thyroid ultrasound elastography. Compared with external compression elastography, we found that thyroid elastography with intrinsic compression can produce reliable results.
本研究旨在评估甲状腺超声弹性成像的观察者间一致性和观察者内可重复性。
本前瞻性研究于 2010 年 12 月至 2011 年 3 月期间纳入了 56 例患者（56 个结节）。所有患者均因细针穿刺活检发现结节恶性、可疑恶性或滤泡/ Hurthle 细胞肿瘤而接受甲状腺手术。在每位患者上，三位内分泌学家使用商业超声机进行超声弹性成像检查。由于使用颈动脉搏动进行了内部压迫，因此未施加外部压迫。每位内分泌学家对同一甲状腺结节重复进行弹性成像检查。内分泌学家在描绘结节边界后，通过交互方式确定量化结节内局部应变对比的弹性对比指数。较大的弹性对比指数值表示结节恶性的可能性增加。Pearson 相关系数用于评估测量的弹性对比指数值的观察者间和观察者内一致性，p 值<0.05 被认为具有统计学意义。
在甲状腺超声弹性成像中发现了显著的观察者间和观察者内一致性。两位观察者之间的 Pearson 相关系数分别为 0.79（观察者 1 和 2，p<0.01）、0.77（观察者 1 和 3，p<0.01）和 0.73（观察者 2 和 3，p<0.01）。观察者 1、2 和 3 的观察者内一致性的 Pearson 相关系数分别为 0.87（p<0.01）、0.73（p<0.01）和 0.84（p<0.01）。
甲状腺超声弹性成像具有良好的观察者间和观察者内一致性。与外部压迫弹性成像相比，我们发现使用固有压迫的甲状腺弹性成像可以产生可靠的结果。
