CURRENT CONCEPTS IN MAGNETIC RESONANCE IMAGING OF HEPATOCELLULAR CARCINOMA AND LIVER METASTASES WITH USE OF NON-SPECIFIC AND SPECIFIC CONTRAST MEDIA

Abstract
Presence and characterization of focal liver lesions is of fundamental importance in abdominal MR imaging. An abundance of benign and malignant lesions with various appearances in MR imaging can be found. Since both malignant and benign lesions may occur concomitantly in the same patient, it is of decisive importance not only to detect but to characterize a lesion. This is particularly mandatory if a surgical procedure or multimodal therapy concepts are planned. Intravenously administered, non-specific contrast agents have been used in abdominal MR imaging for more than fifteen years. This category of contrast agents -typically Gadolinium (Gd)-chelated compounds - has properties similar to those of extracellular space (ECS) contrast agents used in iodine-enhanced CT. Various efforts have been made over the last decade to develop contrast agents that combine the excellent contrast resolution of MRI with an improved tissue specificity. These contrast media have been divided into two categories according to their target cell population: substances tailored to the reticuloendothelial system (RES) of the liver and compounds targeted to hepatocytes. In the following article, we will discuss the different classes of contrast agents regarding their biodistribution, pharmacokinetic properties, typical imaging features, and clinical impact.

Key words
contrast media, gadolinium, ferumoxides, liver, magnetic resonance imaging

Bibliografía del artículo
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