Department of Radiology, University of Yamanashi, Shimokato, Chuo, Japan.
Jpn J Radiol. 2010 Oct;28(8):623-7. doi: 10.1007/s11604-010-0478-1. Epub 2010 Oct 24.
The aim of this study was to estimate inter-rater reliability and validate magnetic resonance elastography (MRE) as a tool to measure liver elasticity.
The study protocol was approved by the institutional review board at our institution. In all, 10 normal volunteers and 110 patients, who provided written informed consent, were enrolled. The pathological fibrosis score was applied as a standard reference of liver fibrosis in 21 patients. MRE was performed with a 1.5-T magnetic resonance imaging scanner with a cylindrical passive longitudinal shear wave driver placed over the right chest wall to deliver vibrations. A gradient-echo MRE sequence was used to acquire axial wave images, which were automatically converted to elastograms representing elasticity (in kilopascals, or kPa). The region of interest was placed in the right lobe of the liver on elastograms by two raters independently. To evaluate interrater reliability, the intraclass correlation coefficient was calculated. The elasticity measurements correlated with the pathological fibrosis score (F1-F4) in 21 patients.
The intraclass correlation coefficient was almost perfect (0.993) between the elasticities measured by the two raters. The mean elasticity value for patients with F4 was 5.7 kPa; F3, 4.4 kPa; F2, 3.1 kPa; F1, 2.2 kPa; and F0, 2.1 kPa.
MRE is a reliable tool to measure liver elasticity.
本研究旨在评估磁共振弹性成像（MRE）测量肝脏弹性的可靠性，并验证其作为一种测量工具的有效性。
本研究方案已获得我院机构审查委员会的批准。共有 10 名正常志愿者和 110 名签署了书面知情同意书的患者参与了本研究。21 名患者应用病理纤维化评分作为肝脏纤维化的标准参考。MRE 在 1.5T 磁共振成像扫描仪上进行，在右胸壁上放置一个圆柱形被动纵向剪切波驱动器以产生振动。使用梯度回波 MRE 序列采集轴向波图像，这些图像自动转换为代表弹性的弹性图（以千帕斯卡，kPa 为单位）。两名评估者在弹性图上独立地将感兴趣区域放置在肝脏的右叶。为了评估评估者之间的可靠性，计算了组内相关系数。在 21 名患者中，弹性测量值与病理纤维化评分（F1-F4）相关。
两名评估者测量的弹性之间的组内相关系数几乎为完美（0.993）。F4 患者的平均弹性值为 5.7kPa；F3 为 4.4kPa；F2 为 3.1kPa；F1 为 2.2kPa；F0 为 2.1kPa。
MRE 是一种可靠的测量肝脏弹性的工具。
