Imaging of NAFLD

The role of imaging in the assessment of non-alcoholic fatty liver disease (NAFLD) is expanding; it now includes the diagnosis, severity grading, and longitudinal monitoring of hepatic steatosis. Imaging also permits assessment of the advanced features of NAFLD and its complications, such as fibrosis, cirrhosis, portal hypertension, and hepatocellular carcinoma. In addition, imaging is frequently utilized to measure primary or secondary endpoints in NAFLD-related research studies. Ultrasound (US), computed tomography (CT), and magnetic resonance (MR) techniques are useful noninvasive tools for these purposes. Conventional grayscale US, unenhanced CT, and in- and out-of-phase MR methods have established roles in the detection of steatosis. Refinements of these methods allow quantification of the severity of steatosis. New imaging techniques that quantify elastic, perfusion, and diffusion properties of the liver show promise for assessment of fibrosis and pre-clinical cirrhosis, and they are increasing in clinical availability. Imaging techniques for the differentiation between steatohepatitis and isolated steatosis are in development or in early phases of evaluation, but developments in this exciting area have not yet been validated.