Liver assessment with diffusion weighted imaging

PURPOSE : Assesing the usefulness of DWI in liver lesions and parenchymal disorders.MATERIALS AND METHODS: Using free-breathing technique with a b value of 600 mm2/sn, ADC measurements were calculated for 364 focal liver lesions (181 benign, 142 metastatic and 41 HCC lesions) and 152 liver parenchyma (94 normal, 17 chronic parenchymal disease, 12 hemochromatosis, 22 advanced steatosis, 4 cirrhosis and 3 hepatomegaly) using DWI images obtained from 392 patients. For all lesions, ratio of lesion ADC to parenchyma ADC were calculated to obtain a cut-off value in discriminating malign from benign lesions.RESULTS: ADC values were found to be statistically different between benign and malign lesions, hemangioma and metastasis, hemangioma and HCC (p<0,001). For malignant lesions under the cut-off value of 184.5x10-5 mm2/sn sensivity of %76 and a specifity of %77 were determined. Using lesion to parenchyma ratios a sensivity of %76 and specifity of %87 was obtained using a cut-off value of 1,242. For patients with hepatosteatosis and hemochromatosis, parenchymal ADC values were found to be statistically lower than the normal population.CONCLUSION : Using ADC measurements and `lesion-to-parenchyma ratio?, DWI is an new and useful application which supplements dynamic contrast enhanced MRI sequences in discriminating benign and malignant liver lesions and its parenchymal disorders.