Comparison of a 1.0 molar and a 0.5 molar formulation of gadobutrol in dynamic MR imaging of the liver in rats with hepatocellular carcinoma.

The efficacy of a 1.0 molar formulation of gadobutrol was compared with that of a 0.5 molar formulation in dynamic magnetic resonance (MR) imaging of the liver in rats with hepatocellular carcinoma (HCC). Seven nodules histologically identified as moderately differentiated HCC underwent dynamic study. In the normal parenchyma surrounding these tumors, the 0.5 molar and 1.0 molar formulations yielded similar enhancement patterns, with maximum enhancement value of approximately 35% at 20 to 40 s after injection. In the tumors, the 0.5 molar formulation induced approximately 65% enhancement, whereas the 1.0 molar formulation, used at the same dose as the 0.5 molar formulation, induced significantly higher enhancement until 10 min after injection with maximum enhancement of approximately 90%. These findings indicate that the 1.0 molar formulation could be more efficacious than the 0.5 molar formulation in dynamic MR studies of moderately differentiated HCC even when injected at the same dose.