Added Value of Diffusion Weighted Imaging for Detecting Pancreatic Abnormality in Patients with Clinically Suspected Acute Pancreatitis

ABSTRACT

PURPOSE: To evaluate the added value of diffusion weighted imaging (DWI) to computed tomography (CT) for detecting pancreatic abnormality in patients with clinically suspected acute pancreatitis (AP). MATERIALS AND METHODS: 203 patients who underwent abdomen CT and subsequent DWI to do a workup for epigastric pain were analyzed. Two blinded radiologists independently performed an interval reading based on CT image sets first, then based on combined CT and DWI image sets. The diagnostic criterion on DWI was the increased signal intensity in the pancreas to that of the spleen. For quantitative analysis, the third radiologist measured ADC value of the pancreas in each patient. RESULTS: For AP (n = 43), the sensitivity for detecting pancreatic abnormality increased, from 42% to 70% for reader 1 (P < 0.05) and from 44% to 72% for reader 2 (P < 0.05). For borderline pancreatitis (n = 42), the sensitivity also increased, from 10% to 26% for reader 1 (P < 0.05) and from 7% to 29% for reader 2 (P < 0.05). The mean ADC values (unit, × 10⁻³ mm²/s) were significantly different among the three groups (for AP, 1.09 ± 0.16; for borderline pancreatitis, 1.28 ± 0.2; for control, 1.46 ± 0.15, P < 0.05). CONCLUSIONS: Sensitivity for detecting pancreatic abnormality increased significantly after adding DWI to CT in patients with clinically suspected AP.