Diffusion-weighted MR imaging of the liver of hepatitis C patients.

Magnetic resonance diffusion-weighted imaging (DWI) of the liver was investigated to determine whether this method could be used to differentiate between the stages of fibrosis and inflammation for hepatitis C viral infection. DWI data were recorded for 18 hepatitis C patients and 10 control subjects using a modified pulse sequence allowing a 52 ms echo time delay. Acquisitions were performed with breath holding using five different b gradient factor values ranging between 50 and 250 s/mm(2) and in the three axes. Apparent diffusion coefficient (ADC) values were measured from a 5.7 cm(2) area in the central region of the liver. The inflammation and fibrosis grades were evaluated histologically on a biopsy sample. The mean ADC values were 2.30 +/- 1.28 x 10(-3) and 1.79 +/- 0.25 x 10(-3) mm(2)/s for hepatitis C patients and control subjects, respectively. Using our technique, no correlation could be found between the ADC values and the inflammation or fibrosis scores, indicating that tissue changes produced by hepatitis C do not appear to be quantifiable by DWI.