Hepatic metastases: use of diffusion-weighted echo-planar imaging.
Diffusion-weighted MR imaging is increasingly applied to detect and characterize focal hepatic lesions. In this update article, technical aspects regarding diffusion-weighted echo-planar imaging (DW-EPI) of the liver will be addressed, and concepts for image interpretation will be provided. The value of DW-EPI for the detection of hepatic metastases is illustrated on the basis of a review of the literature and our personal experience. In this respect, special emphasis is given to the comparison of DW-EPI with well-established MR imaging techniques such as T2-weighted and contrast-enhanced MR imaging, and advantages and limitations of DW-EPI will be described. Based on the review, it is concluded that DW-EPI is more sensitive than T2-weighted MR imaging and at least as accurate as superparamagnetic iron oxide-enhanced or gadolinium-enhanced MR imaging for the detection of hepatic metastases. Although difficulties occasionally arise in further characterizing small lesions detected with DW-EPI, substantial improvements in the preoperative evaluation of liver metastases in candidates for hepatic resection may be expected.
Bruegel
Melanie
M
Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675 Munich, Germany. mbruegel@roe.med.tum.de
Rummeny
Ernst J
EJ
D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D017352:Echo-Planar Imaging; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012680:Sensitivity and Specificity
D003287:Contrast Media