Pancreatic transplants: secretin-stimulated MR pancreatography

Abstract

Our study was aimed to evaluate the functional status of pancreatic transplants using dynamic MR pancreatography after secretin stimulation. Thirteen asymptomatic patients previously submitted to isolated pancreas (n = 6) or combined kidney-pancreas (n = 7) transplantation, with enteric-portal pancreatic drainage, underwent MR examination at 1.5 T using a phased-array coil. After the acquisition of axial and coronal T1- and T2-weighted sequences, dynamic MR pancreatography was performed using a coronal breath-hold, thick-slab (40-60 mm), single-shot T2-weighted fast spin-echo sequence. After the intravenous administration of secretin (Secrelux, Sanochemia; 1 cU/kg body/weight), a single-slice image acquisition was repeated every 30 s up to 15 min. We estimated the calibre changes of the pancreatic ductal system and the filling of the donor's duodenum on the basis of pancreatic secretion after secretin stimulation, also evaluated by using a mean signal intensity/time histogram in a chosen region of interest including the transplanted pancreas and the connected small bowel. All patients well tolerated the examination, and no side effects were reported after secretin administration. In 12/13 cases, a significant increase (more than 1 mm) in the diameter of the mean pancreatic duct was observed after secretin stimulation; in all patients, a noticeable filling of the duodenal graft was demonstrated during dynamic MR pancreatography on both qualitative and quantitative analyses. Dynamic MR imaging after secretin administration allows non-invasive evaluation of exocrine function of the pancreatic transplants and could be used to differentiate patients with graft rejection from those with normal graft function.