Hepatic metastases: computed tomography versus magnetic resonance imaging in 1997.

The developments in computed tomography (CT) and magnetic resonance (MR) imaging that have taken place over the last two decades have dramatically increased our ability to detect and characterize focal liver lesions, and have led to the liver becoming the primary focus of interest in abdominal imaging. At the same time, advances in the medical and surgical treatment of secondary liver tumors have continued to be a challenge to these advances in radiology. It is clear that a successful outcome depends on knowledge of the size and location of the tumor burden, and accurate radiological assessment is crucial in identifying the subgroups of patients who may benefit from surgery and, at the same time, in preventing unnecessary radical surgery, with its high morbidity, in those likely to gain only a short-term benefit. The current period of limited resources, along with increased awareness of the effects of ionizing radiation, has led to competition between the two modalities, with considerable debate as to which offers the better noninvasive examination of the liver, particularly with regard to the detection and characterization of focal liver lesions. Arguments over each method's relative merits have tended to be overstated, but the parallel use of different diagnostic techniques is costly and inefficient. Each needs to be placed in an appropriate position on diagnostic pathways.