Department of Diagnostic Radiology, Institute of Gastroenterology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
J Magn Reson Imaging. 2011 Aug;34(2):345-53. doi: 10.1002/jmri.22671. Epub 2011 Jun 23.
To retrospectively compare the diagnostic accuracy for the detection of colorectal liver metastases between gadoxetic acid-enhanced MRI (EOB-MRI) and diffusion-weighted imaging (DWI) on 3.0 Tesla (T) system, and then to determine whether a combination of the two techniques may improve the diagnostic performance.
Forty-seven patients underwent MR imaging at 3.0T, including DWI (DWI set) and dynamic and hepatobiliary phase EOB-MRI (EOB set) for the preoperative evaluation of colorectal liver metastases. All suspicious metastases were confirmed by hepatic surgery. Two blinded readers independently reviewed three different image sets, which consisted of DWI set, EOB set, and combined set. The accuracy was assessed by the area (Az) under the alternative-free response receiver operating characteristic curve, and the sensitivity and positive predictive value (PPV) were calculated.
We found a total of 78 confirmed colorectal liver metastases in 42 of 47 patients. Each reader noted higher diagnostic accuracy of combined set of EOB-MRI and DWI than DWI set and EOB set, without statistical significance. Regardless of the size of colorectal liver metastasis, each reader detected significantly more metastases on combined set than on DWI set, and PPV was significantly higher with DWI set than with EOB set or with combined set for one reader.
EOB-MRI was more useful for the detection of colorectal liver metastases, while DWI was more useful for their characterization. The combination of EOB-MRI and DWI showed significantly higher accuracy and sensitivity for the preoperative detection of small colorectal liver metastases than DWI.
回顾性比较钆塞酸增强磁共振成像（EOB-MRI）与 3.0T 系统弥散加权成像（DWI）在检测结直肠癌肝转移中的诊断准确性，然后确定两种技术的联合应用是否可以提高诊断性能。
47 例患者在 3.0T 磁共振成像上进行检查，包括 DWI（DWI 组）和动态及肝胆期 EOB-MRI（EOB 组），用于术前评估结直肠癌肝转移。所有可疑转移灶均经肝切除术证实。两名盲法读者独立分析了 DWI 组、EOB 组和联合组这三组不同的图像。通过替代无应答者的接受者操作特征曲线下的面积（Az）来评估准确性，并计算了灵敏度和阳性预测值（PPV）。
我们在 47 例患者中的 42 例中发现了总共 78 个确认的结直肠癌肝转移灶。每位读者均发现联合 EOB-MRI 和 DWI 的诊断准确性高于 DWI 组和 EOB 组，但无统计学意义。无论结直肠癌肝转移灶的大小如何，每位读者在联合组上均能检测到更多的转移灶，且 DWI 组的 PPV 明显高于 EOB 组或联合组，对一名读者而言。
EOB-MRI 对检测结直肠癌肝转移更有用，而 DWI 对其特征分析更有用。EOB-MRI 与 DWI 的联合应用对术前检测小的结直肠癌肝转移灶的准确性和灵敏度均显著高于 DWI。
