Benign liver lesions: differentiation by magnetic resonance

Optimal hepatic imaging involves both detection and characterization of focal lesions. Detection involves both determination of the presence of lesions and of their segmental extent of liver involvement. In the evaluation of hypervascular lesions, magnetic resonance imaging (MRI) has a greater impact on patient management than ultrasound (US) and computed tomography (CT). Most benign tumors are incidental findings and do not produce clinical symptoms. They must be accurately diagnosed without using aggressive procedures. Knowledge of their imaging features is essential to avoid unnecessary work-up and to minimize patient anxiety. In this article, the MR appearance, vascular and functional behavior of the most common benign liver tumors will be discussed.