MRI and MRS of the Liver
The Liver MR imaging group is investigating the role MR imaging, including diffusion weighted imaging and MR spectroscopy, can play in noninvasive assessment of nonalcoholic fatty liver disease (NAFLD) and in changes in the liver and in metabolism due to diet. In particular, we are looking at assessing grades of steatosis and inflammation and the stage of fibrosis in the liver. We have several ongoing studies that include in vivo MR imaging of patients who are going on for a biopsy. In addition to the in vivo MR data, we have clinical and pathological information on these patients, many of whom are part of the UCSF site of the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN), an NIH, NIDDK funded, multicenter study. We are also obtaining high resolution magic angle spinning (HRMAS) spectroscopy from liver tissue samples to help guide our in vivo efforts. Currently, fatty liver disease is definitively diagnosed and assessed using invasive biopsies. In view of the high population prevalence of NAFLD, a non-invasive mode of distinguishing the relatively benign condition of simple fatty liver (or steatosis) from the more progressive form, Non Alcoholic Steatohepatitis (NASH) would be preferable and very broadly applicable. Our preliminary data shows striking MR differences between normal and diseased patients and among the different grades of steatosis, demonstrating the potential promise of MR for the noninvasive evaluation of fatty liver disease.