Chronic Hepatitis and Fibrosis Assessed by Magnetic Resonance Elastography (MRE)

INTRODUCTION: Liver fibrosis results from chronic liver disease, including chronic viral hepatitis, non-alcoholic steatohepatitis (NASH), inborn errors of metabolism, and toxic damage. Characterizing severity of fibrosis is essential for prediction of disease progression and therapy. Recently, ultrasonographic (US) elastography and magnetic resonance elastography (MRE) have been used to detect and quantify liver fibrosis [1, 2, 3, 4]. A significant correlation between elasticity of liver tissue and severity of fibrosis has been demonstrated on both transient US elastography and MRE. Besides fibrosis, other causes of elevated pressure include acute liver injury, hepatitis, portal vein hypertension and cellular infiltration, which may all increase liver stiffness. Salameh et al documented that steatohepatitis can be detected by increased stiffness value on MRE using an animal model [4]. Therefore, the purpose of our study was to evaluate the capability of MR elastography (1) in detecting histologic activity before the appearance of fibrosis in patients with various chronic liver diseases; (2) in discriminating histologic activity from tissue lacking inflammation and fibrorsis, and tissue with various stages of fibrosis and inflammation.