Fibroscan® Medical Device, Assessment for Non Invasive Diagnosis of Liver Steatosis

Hypothesis of this study is the existence of a relation between parameters measured by FibroScan® FS 502 according to our non invasive method and liver steatosis condition.

This proof of concept validation is made up of two steps:

* Step 1: feasibility study of the method on 10 healthy volunteers
* Step 2: diagnosis study on 50 healthy volunteers (25 between 18-30 years-old and 25 between 40-65 years-old) and on 25 patients whom cares including an liver biopsy et whom the histological answer is clean steatosis (NAFLD).

Experimental procedures consist in:

* Fibroscan measure, preceded by tracking ultrasonography.
* liver MRI (for substudy about MRI comparison, in step 2)
* a blood test for biological assessment of liver functions

Diagnosis of liver lipid overload (named liver steatosis), unrelated to alcohol consumption, still mainly based on histological exam of the liver. An histological continuity exists going from clean liver steatosis (Non Alcoholic Fatty Liver Disease, NAFLD) to steatohepatitis with signs of inflammation and tissue fibrosis (Non Alcoholic Steato-Hepatitis, NASH). It's now well-known that disease can evolve to cirrhosis and its complications.

Hypothesis of this study is the existence of a relation between parameters measured by FibroScan® FS 502 according to our non invasive method and liver steatosis condition.

This proof of concept validation is made up of two steps:

* Step 1: feasibility study of the method on 10 healthy volunteers
* Step 2: diagnosis study on 50 healthy volunteers (25 between 18-30 years-old and 25 between 40-65 years-old) and on 25 patients whom cares including an liver biopsy et whom the histological answer is clean steatosis (NAFLD).

Measures on healthy volunteers enable to do an intra-operator reproductibility analysis, a study of an age effect and a search of potential mechanic aging of the liver.

Experimental procedures consist in:

* Fibroscan measure, preceded by tracking ultrasonography.
* liver MRI (for substudy about MRI comparison, in step 2)
* a blood test for biological assessment of liver functions

The final aim of this study is to propose a device enable medical community to do in vivo hepatic rheology observation, highly correlated to liver lipid overload. After industrialization of this innovation, this diffusion could making easier patients follow-up.

Eligibility Criteria:
Inclusion Criteria:

* Healthy subjects - Steps 1 and 2

  * Age between 18 and 65 years old (2 age groups for step 2 : 18-30 et 40-65 years-old)
  * Written inform consent form signed
  * Affiliated to medical insurance
  * Alcohol consumption d'alcool \< 20g/j for women, \<30g/j for men
* Patients with liver steatosis - Step 2

  * More than 18 years -old
  * Written inform consent form signed
  * Affiliated to medical insurance
  * Patients with clean steatosis confirmed by histological results of a liver biopsy done the previous month
  * Alcohol consumption d'alcool \< 20g/j for women, \<30g/j for men

Exclusion Criteria:

* Healthy subjects - Step 1

  * Exposure to chemical poisons (solvents, paints, drugs) in the previous 4 weeks
  * Pregnant women, lactating women, and women in age for procreation and without reliable contraception
  * Presence of ascites
  * Person under guardianship
* Healthy subjects - Step 2

  * Exposure to chemical poisons (solvents, paints, drugs) in the previous 4 weeks
  * Pregnant women, lactating women, and women in age for procreation and without reliable contraception
  * Contraindication to MRI
  * Presence of ascites
  * Person under guardianship
* Healthy subjects - Steps 1 and 2

  * Presence of liver tumor or ascites (diagnosed with MRI or ultrasonography)
  * Abnormal liver function tests (increase of transaminases, gammaGT)
* Patients with liver steatosis - Step 2

  * Exposure to chemical poisons (solvents, paints, drugs) in the previous 4 weeks
  * Pregnant women, lactating women, and women in age for procreation and without reliable contraception
  * Contraindication to MRI
  * Presence of ascites
  * liver tumor
  * Serology anti VHC+ or Ag HBs+
  * Infection by HIV
  * Auto-immun hepatitis
  * Genetic hemochromatosis, Wilson disease, lake of alpha-1-antitrypsin
  * Fibrosis or liver cirrhosis at biopsy
  * Person under guardianship