[Magnetic resonance imaging study of liver metastases]

Eighty-three hepatic metastases from a variety of primary neoplasms were studied with magnetic resonance (MR) imaging. T1 and T2-weighted pulse sequences were employed at a 0.6 T field strength magnet. The results revealed that from multi-echo T2 weighted images it seems to be possible to distinguish hypovascular and hypervascular metastatic nodules. Ninety-one percent of target, bull eye and ring signs were present in hypovascular metastases, such as gastrointestinal adenocarcinoma and breast cancer. Eighty eight percent of light bulb sign were present in hypervascular metastases which include endocrine tumors, sarcomas, some lung cancer and renal cell carcinoma. In view of the different vascularity of metastatic nodules, there is less problem to differentiate hypovascular nodules from hemangioma. However it is rather difficult to differentiate the hypervascular metastatic nodules from hemangioma.