Assessment of diagnostic value of DWI technique in the evaluation of liver fibrosis

Introduction: The liver fibrosis is caused by extracellular accumulation of cluster, glycos amino glycans and proteoglycans, which this extracellular accumulation may limit the penetration and molecular movement of water in the tissue, so the Diffusion weighted imaging(DWI) technique is due to the sensitivity to the movement and release of water molecules Can show this restriction. Using this technique, in addition to examining the entire liver, sections of the liver tissue most affected by fibrosis can also be identified. The purpose of this study was to evaluate the use of apparent diffusion coefficient (ADC) measurement in DWI imaging technique and to investigate the correlation between this method and the method of sampling in patients.   Materials and Methods: Twenty-five chronic viral hepatitis C patients were examined by 1.5 Tesla MR scanner with diffusion gradient encoding in three orthogonal directions at b-values of (200, 500, 700, and 1000 s/mm2). They were correlated to biopsy finding and graded according to Ishak scoring system. Hepatic ADC values were measured for patients.   Results: The best correlation between ADC values and biopsy were seen at b-values 200, 700, and 1000 s/mm2. lesser correlation was obtained at b-values of 500 s/mm2. Cut off values between different grades of fibrosis were calculated and presented in the text. Conclusion: ADC measured with DWI is a reliable non-invasive technique for quantification of liver fibrosis, and could replace liver biopsy in certain cases.