Role of Diffusion Weighted MRI in Diagnosis and Characterization of Focal Hepatic Lesions

Abstract

The liver is an organ in which various benign and malignant (primary orsecondary) masses can be detected. Therapy requires an accurate diagnosis, which in turn relies primarily onappropriate imaging and image-guided biopsy. Although the primary modalities for liver imaging are ultrasound and computed tomography,recent studies have suggested that MRI is the most sensitive method for detecting small liver metastatic lesions, and MRI is now considered the pre-operativestandard method for diagnosis. Magnetic resonance imaging (MRI) is establishing a role as a primarydiagnostic technique with evidence showing MR to have advantages overcomputed tomography (CT) as regards diagnostic sensitivity and specificity for many pathologies of solid organs and so MRI is preferred when further characterization of these masses is needed. MRI plays an increasingly important role in the evaluation of patients with liver disease because of its high contrast resolution, lack of ionizing radiation, and the possibility of performing functional imaging sequences. MRI has many sequences that help in detection of hepatic focal lesions and in reaching the diagnosis easily even without contrast injection or the need for biopsy.