Value of magnetic resonance cholangiopancreatography with secretin stimulation in the evaluation of pancreatic exocrine function after pancreaticogastrostomy

Background/Purpose The aim of this study was to assess the value of magnetic resonance cholangiopancreatography with secretin stimulation (secretin‐MRCP) in evaluating the remnant pancreatic exocrine reserve after pancreaticogastrostomy with pancreaticoduodenectomy. Methods Forty‐three patients who had undergone pancreaticoduodenectomies and who were given pancreaticogastrostomies for reconstruction were studied. Dynamic MRCPs, using a half‐Fourier acquisition single‐shot turbo spin‐echo (HASTE) sequence were obtained before and up to 10 min after secretin administration. The morphologic features and diameter of the main pancreatic duct were monitored and graded before and after secretin stimulation. The results were compared with those of endoscopic findings, secretin stimulation testing with a collection of pancreatic fluid, N‐benzoyl‐l‐tyrosyl‐p‐aminobenzoic acid (BT‐PABA) excretion testing, and fecal chymotrypsin concentration. Results The results of secretin‐MRCP were classified into three distinct groups: a good‐secretion group (group 1; n = 22; 51%), a moderate‐secretion group (group 2; n = 10; 23%), and a poor‐secretion group (group 3; n = 11; 26%). This MRCP classification correlated significantly with the concentrations of the pancreatic enzymes p‐type amylase, lipase, and trypsin in the gastric juice. The BT‐PABA test value was 59.8% in group 1, 46.1% in group 2, and 46.5% in group 3, and was significantly higher in group 1 than in groups 2 or 3. The fecal chymotrypsin concentration was 20.5 U/g in group 1, 14.5 U/g in group 2, and 0.7 U/g in group 3, and there was a significant correlation between the MRCP classification and fecal chymotrypsin concentration. Conclusions MRCP with secretin stimulation favorably reflected the presence of remnant pancreatic exocrine function. Therefore, secretin‐MRCP is a feasible and effective follow‐up examination method to evaluate remnant pancreatic exocrine function after pancreaticogastrostomy.