Purpose. To demonstrate the usage of MR spectroscopy (MRS) in the diagnostic algorithm of a patient with non-alcoholic steatohepatitis (NASH).

Materials and methods. We present the clinical case of a 41-year-old patient suffering from nonalcoholic fatty liver disease at the stage of steatohepatitis.  The patient's  medical history

was studied, the data during the initial examination and after 6 months of therapy were evaluated. During the initial examination an ultrasound examination and liver biopsy were carried out, data of the clinical examination were obtained. Biochemical blood tests and liver MR spectroscopy were performed twice before and after treatment.

Results. Background MR spectroscopy showed the fat content in the liver of 32%. The treatment was contributed to reduce the patient's weight by 10% and reduce the level of ALT. The fat content in the liver estimated by MRS after 6 months of treatment reduced (up to 27%).

Discussion. Progression of NASH causes the developing of fibrotic changes in the liver parenchyma, up to the formation of cirrhosis. Factor that is directly associated with the risk of fibrosis development is the degree of fatty infiltration of the liver. Proton MR spectroscopy provides non-invasive and accurate quantification of fat content. Using this technique during initial examination of a patient with NASH can be a significant component of risk stratification and be one of the key points for prescription of hepatic morphological examination.

Conclusion. Proton MR spectroscopy is indicated in the initial diagnosis of NASH to accurately quantify the degree of hepatic steatosis.