Contrast-enhanced MR imaging of the liver

Postcontrast images with a 0.1 mmol/kg dose of a gadolinium chelate with extracellular distribution, when acquired dynamically during breath holding, can improve both differential diagnosis and lesion recognition in liver MR imaging. Initial results at 0.3 mmol/kg, compared with 0.1 mmol/kg, suggest a substantial improvement in lesion identification at the high dose, as assessed by using signal intensity difference divided by noise. Of the gadolinium chelates with predominantly renal excretion, only gadoteridol is presently approved in the United States at the high dose, with limited clinical evaluation for liver imaging performed to date. For linear chelates, such as gadopentetate dimeglumine and gadodiamide injection, the degree to which release of free gadolinium ion occurs is a possible issue because of lower in vivo stability (42,43). Preliminary results with hepatobiliary gadolinium chelates and iron particulate agents are favorable with regard to efficacy, although these agents remain in clinical trials.