Chronic pancreatitis:: Evaluation of pancreatic exocrine function with MR pancreatography after secretin stimulation

PURPOSE: To compare duodenal filling seen at magnetic resonance (MR) pancreatography after secretin stimulation and biochemical parameters determined with the intraductal secretin test (IDST) for evaluation of pancreatic exocrine function. MATERIALS AND METHODS: MR pancreatography after secretin stimulation and IDST were performed in 41 patients with chronic pancreatitis (group 1) and eight patients with other pancreatic disease (group 2). A control group (group 3, n = 28) underwent MR pancreatography after secretin stimulation only. MR pancreatograms were acquired before and every 30 seconds for 10 minutes after secretin injection. Duodenal filling was graded from least amount of filling (grade 1) to normal filling (grade 3) on the last MR pancreatogram. Pancreatic exocrine function was determined at IDST, Main pancreatic ductal diameter was compared between groups 1 and 3. RESULTS: All ductal diameters were significantly larger in group 1 (P < .001). The maximal diameter variation after secretin stimulation was significantly higher in the control group (P = .001). pancreatic exocrine function parameters determined at IDST were significantly lower in patients with grade 1 duodenal filling than in those with grade 2 or 3 (P < .05). Maximal bicarbonate concentration alone was independently associated with all grades of duodenal filling (P = .007). The sensitivity and specificity of reduced duodenal filling for assessment of reduced pancreatic exocrine function were 72% and 87%, respectively. CONCLUSION: Duodenal filling grade determined at MR pancreatography after secretin stimulation allows specific estimation of pancreatic exocrine function.