steatosis is a disease of the liver which causes a rise of
triglycerides following a constant inflammation of the hepatocytes.
Asymptomatic, it can often leads to more severe diseases like
diabetes or cancer. The histopathologic analysis by biopsy remains the
most reliable method up to now to diagnose steatosis but it
comprises the significant disadvantage to be invasive for the patient.
A non invasive technique, the proton magnetic resonance spectroscopy
(MRS), recently allowed to show that it is possible to quantify
triglycerides in the liver. Other techniques of imagery can be added
with spectroscopy, like diffusion weighted imaging (DWI) and double
echo MRI (DEI). The first measures displacements of water
through tissues whereas last measure the quantity of fat present within
a tissue. Biochemically speaking, the titration of enzymatic activity,
especially the aspartate aminotransferase (AST) on alanine
aminotransferase (ALT) ratio, allows to distinguish the alcoholic or
non-alcoholic origin of the steatosis. Finally, analysis of the
metabolites contained in a biological fluid, named metabonomic, allows
quantify several metabolites.
To determine which methods and which parameters (magnetic resonance,
bioassays and metabonomic) allow to better evaluate the hepatic degree
of steatosis in a non-invasive way and to differentiate the alcoholic
steatosis from the non-alcoholic steatosis.