Cellular MR Imaging of the Liver Using Contrast Agents
Magnetic resonance imaging (MRI) is considered a state-of-the-art technique for liver imaging. It is superior to other imaging modalities because the anatomic resolution provided by MR images is as low as 1 to 2 mm in-plane at clinical field strengths of 1.5 tesla and tissue-specific techniques can aid to further characterize pathologic conditions in the liver. The liver contains a vascular and biliary network within different types of cells. Extracellular gadolinium chelates have been used for liver imaging. With the use of extracellular contrast agents, focal liver lesions and diffuse parenchymal pathologies in the liver can be evaluated based on contrast agent dynamics within the vascular tree of the liver. Cellular contrast agents have been developed in the past 10 to 15 years for liver MRI, which are distinctively taken up by liver cells. The use of cellular contrast agents is helpful for further evaluation of liver disease.