1 Department of Radiology, School of Medicine, Ankara University, Talatpaşa Bulvari, Sihhiye, 06100, Ankara, Turkey.
AJR Am J Roentgenol. 2014 Jan;202(1):74-82. doi: 10.2214/AJR.12.10359.
The purpose of this article is to determine the added diagnostic value of T1-weighted gradient-echo in-phase images obtained during MRCP in the detection and differentiation of hepatolithiasis and intrahepatic pneumobilia.
Intrahepatic bile ducts in 47 patients were scored in terms of their possibility of containing biliary stone and air. MRI was performed with a 1-T system for 32 patients and with a 3-T system for 15 patients. Two radiologists independently reviewed two sets of MRI scans: set 1 included T2-weighted MRCP images, and set 2 included T2-weighted MRCP images plus T1-weighted gradient-echo in-phase images. The diagnostic performances of set 1 and set 2 in the evaluation of the bile ducts containing air or stone and bile ducts containing neither of them were analyzed using the area under the receiver operating characteristic curve (AUC) for clustered data. The sensitivities and specificities of both image sets to detect intrahepatic stone or air were also calculated and compared.
For the diagnosis of hepatolithiasis, the AUC obtained from set 2 (0.983) was significantly higher than that obtained from set 1 (0.879; p = 0.037). For the diagnosis of pneumobilia, the AUC obtained from set 2 (0.965) was also significantly higher than that of set 1 (0.765; p = 0.002). With use of percutaneous transhepatic cholangiography, ERCP, and CT as the reference standards, the sensitivity of set 2 (97.1%; 95% CI, 91.1-100%) was significantly higher than that of set 1 (74.3%; 95% CI, 56.7-91.9%) in detecting intrahepatic stones (p = 0.011). For the detection of pneumobilia, the sensitivity of set 2 (98.5%; 95% CI, 95.4-100%) was also significantly higher than that of set 1 (70.8%; 95% CI, 57.7-83.3%; p = 0.000).
The addition of T1-weighted gradient-echo in-phase images to standard MRCP sequences improves the detection and differentiation of hepatolithiasis and intrahepatic pneumobilia.
本文旨在确定磁共振胰胆管成像(MRCP)中 T1 加权梯度回波同相位图像在检测和鉴别肝内胆管结石和胆内积气中的附加诊断价值。
对 47 例患者的肝内胆管进行评分,以确定其是否含有胆管结石和空气。32 例患者采用 1.0T 系统进行 MRI 检查,15 例患者采用 3.0T 系统进行 MRI 检查。两位放射科医生分别对两组 MRI 扫描结果进行了独立评估:一组为 T2 加权 MRCP 图像,另一组为 T2 加权 MRCP 图像加 T1 加权梯度回波同相位图像。使用聚类数据的受试者工作特征曲线(ROC)下面积(AUC)分析两组评估含气或含石胆管和不含气或含石胆管的诊断性能。还计算并比较了两组图像对检测肝内结石或空气的敏感性和特异性。
对于肝内胆管结石的诊断,组 2 的 AUC(0.983)明显高于组 1(0.879;p=0.037)。对于胆内积气的诊断,组 2 的 AUC(0.965)也明显高于组 1(0.765;p=0.002)。以经皮肝穿刺胆管造影术、内镜逆行胰胆管造影术和 CT 作为参考标准,组 2(97.1%;95%CI,91.1%-100%)在检测肝内结石方面的敏感性明显高于组 1(74.3%;95%CI,56.7%-91.9%)(p=0.011)。在检测胆内积气方面,组 2(98.5%;95%CI,95.4%-100%)的敏感性也明显高于组 1(70.8%;95%CI,57.7%-83.3%;p=0.000)。
在标准 MRCP 序列中增加 T1 加权梯度回波同相位图像可提高肝内胆管结石和胆内积气的检测和鉴别能力。