Assessment of sequential enhancement patterns of focal nodular hyperplasia and hepatocellular carcinoma on mangafodipir trisodium enhanced MR imaging.

RATIONALE AND OBJECTIVES: Sequential contrast changes of mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance imaging (MRI) were evaluated in the differentiation of focal nodular hyperplasias (FNH) and hepatocellular carcinomas (HCC). METHODS: Patients with FNH (n = 16) or HCC (n = 12) underwent MRI: T2-weighted fast spin echo before and T1-weighted gradient echo before and 1, 4, 14, and 22 hours after 5 micromol/kg Mn-DPDP. Homogeneity of enhancement and delineation of fibrous scars of FNHs were assessed qualitatively. Lesion-to-liver contrast changes of FNHs and HCCs were compared quantitatively (Mann-Whitney U). RESULTS: Mn-DPDP improved detection of characteristic scars of FNHs from 50% before to 90% after contrast agent. Apart from fibrous tissue enhancement of FNHs was mostly homogeneous (90%). Time-dependent contrast changes were up to 20 times higher (after 4 hours) for FNHs than HCCs (P < 0.0001). CONCLUSIONS: Mn-DPDP-enhanced MRI helps to delineate characteristic morphologic features of FNHs and can provide quantitative data differentiating FNH and HCC.