Diffusion-weighted MRI for differential diagnosis in gallbladder lesions with special reference to ADC cut-off values.

Hepato-Gastroenterology 2013; 60:00-00 doi 10.5754/hge121155 © H.G.E. Update Medical Publishing S.A., Athens Background/Aims: We retrospectively evaluated the usefulness of the apparent diffusion coefficient (ADC) measured from high-b value diffusionweighted imaging (DWI) of magnetic resonance imaging for the differential diagnosis of gallbladder lesions among patients with cancer, adenoma and inflammatory disease. Methodology: Forty patients with gallbladder lesions (22 patients with cancer, 7 patients with adenoma, and 11 patients with inflammatory disease) were enrolled in this study. All patients underwent high-b value DWI, and the ADC value was measured. The cut-off values were determined by receiver operating characteristic analysis. Results: The ADC values of gallbladder cancers (1.31±0.57x10-3 mm2/s) were smallest and those of adenomas (2.66±0.43x10-3 mm2/s) were largest among the diseases. Inflammatory diseases took a middle position (1.97±0.54x10-3 mm2/s) between them. There were significant differences among the 3 groups of diseases (p<0.05). The cutoff value within ADC values to discriminate cancer from the other diseases was 1.64x10-3 mm2/s (accuracy 87.5%), and that to discriminate adenoma was 2.25x10-3 mm2/s (accuracy 90.0%). Conclusions: The ADC values measured from high-b value DWI would be useful for the differential diagnosis of gallbladder lesions. ABSTRACT