Non Invasive Measurements of Fibrosis, Inflammation and Steatohepatitis in Morbidly Obese Patients

Fatty liver most frequently corresponds to a fat overload of the liver. It is usually classified as alcoholic steatosis or non-alcoholic steatosis. In the case of non alcoholic fatty liver overload, the histological spectrum ranges from simple steatosis to steatohepatitis (NASH) which associates inflammation to steatosis, with a risk of progression to fibrosis and cirrhosis. Obese patients are at particular risk of NASH. Screening of these hepatic lesions is difficult especially as they may exist while the liver tests are normal. The diagnosis of NASH is currently done by liver biopsy, which exposes them in particular to the risk of hemorrhagic complications. Number of subjects required: According to the literature and data collected Louis Mourier in the recent years, the inclusion of 200 patients would examine 20-40 patients with severe histological steatosis and steatohepatitis. All patients will be included in Louis Mourier hospital. Follow-up: one month Search duration: 37 months Duration inclusions: 36 months The total duration of participation for a patient will be one month. Methodology: It is a monocentric, prospective study evaluating the value of noninvasive tests for the diagnosis of hepatic lesions in morbid obese patients. The "open " MRI system allows access to MRI for all obese patients (maximum weight 250 kg). Three of such systems are available in France and liver pathology can be explored only on the system of Louis Mourier. The reference method is liver histology; studied tests are abdominal MRI, Fibroscan / CAP, and serum tests. Examinations required specifically for research Examinations required specifically for the research is abdominal MRI, FibroScan/ CAP and serum tests. Primary endpoint : To validate the use of abdominal MRI, the FibroScan/ CAP and serum tests for finding severe steatosis and / or NASH, specificity, sensitivity, positive and negative predictive values of these tests are calculated. The gold standard is t