DEFINITION OF LIVER-TUMORS IN THE PRESENCE OF DIFFUSE LIVER-DISEASE -COMPARISON OF FINDINGS AT MR-IMAGING WITH POSITIVE AND NEGATIVE CONTRAST AGENTS

PURPOSE: The potential to define liver tumors at magnetic resonance (M R) imaging was compared with a positive and a negative contrast agent (gadoxetic add disodium, or gadolinium EOB-DTPA [a hepatocyte-directed agent], and ferumoxides, or superparamagnetic iron oxide particles [a Kupffer cell-directed agent], respectively) in normal rats and in rat s with induced acute hepatitis, fatty liver, or cirrhosis. MATERIALS A ND METHODS: Rats with implanted liver adenocarcinomas were divided int o four groups: no diffuse liver disease (''normal'' [n = 6]) and diffu se liver diseases (induced acute hepatitis [n = 6], fatty liver [n = 6 ],or cirrhosis [n = 6]). Rats first received gadoxetic acid disodium ( 50 mu mol/kg) and then, 45 minutes later, ferumoxides (10 mu mol/kg). Liver signal intensity enhancement and tumor-to-liver contrast-to-nois e ratio (C/N) were measured in each group. RESULTS: Mean liver signal intensity enhancement values with gadoxetic acid disodium and ferumoxi des were excellent in the normal liver model (176% and -62% respective ly; P < .01) but were significantly reduced in the acute hepatitis mod el (82% and -36%, respectively). In the fatty livers compared with the normal livers, enhancement with gadoxetic acid disodium was reduced ( 57%) but with ferumoxides was excellent (-55%). In the cirrhotic liver s compared with the normal livers, enhancement with gadoxetic acid dis odium (174%) was virtually the same but was impaired with ferumoxides (-43%). CONCLUSION: Hepatic enhancement and tumor-to-liver C/N with ei ther positive or negative liver-enhancing agents can be impaired by th e presence of underlying liver disease. Prior knowledge of the type of diffuse liver disease may influence the choice of contrast agent for tumor detection.