Usefulness of Diffusion Weighted Imaging and Apparent Diffusion Coefficient in Characterizing Pancreatitis and Pancreatic Adenocarcinoma

Abstract

BACKGROUND The main purpose of this article is to establish the usefulness of Diffusion Weighted Imaging (DWI) and Apparent Diffusion Coefficient (ADC) as complementary tools to conventional MRI sequences in characterizing benign (pancreatitis) and malignant (pancreatic adenocarcinoma) pancreatic pathologies in comparison to a control group. METHODS A prospective observational study was done over a period of two years with images obtained using Siemens Magnatom Avanto 1.5T MRI. 130 patients with pancreatic abnormalities were included in this study. An additional control group included 32 patients with normal pancreatic parenchyma. MRI findings including DWI and ADC values were calculated for all patients which was then correlated with clinical, lab and histopathological data. RESULTS Out of the 130 positive cases, 116 (89 %) were benign and 14 (11%) were malignant lesions based on MRI features. Benign lesions include acute pancreatitis (47%), acute on chronic pancreatitis (11%) and chronic pancreatitis (31%). Rest of the cases were pancreatic adenocarcinomas (11%). There was significant reduction of ADC values in patients with acute pancreatitis (mean ADC-1.016 x 10-3), acute on chronic pancreatitis (mean ADC-1.122 x 10-3) and chronic pancreatitis (mean ADC-1.277 x 10-3) as well as pancreatic carcinoma (mean ADC-0.934 x 10-3) in comparison with the control group (mean ADC-1.363 x 10-3). CONCLUSIONS DWI with ADC mapping can play a significant role in the evaluation of pancreatic diseases. It can help in differentiating benign and malignant disease (ADC values of malignancy are significantly lower than benign disease).