Secretin-stimulated MR cholangiopancreatography (MRCP): visualization of the normal pancreatic duct in comparison with ERCP

Purpose: To determine whether the application of secretin improves the depiction of the normal pancreatic duct and to document the time course of any possible improved visualisation. Patients and Methods: Twenty-eight patients with a normal pancreatic ductal system, proved by ERCP, were prospectively enrolled in our study. MRCP was carried out in a 1.0 Tesla unit using a thick slab single-shot turbo-echo sequence (TR: infinity TE: 1100 ms, FA: 150degrees, slab thickness: 65 mm). Following acquisition of a non-enhanced image, 1 clinical unit/kg bodyweight of secretin was injected intravenously. During the subsequent ten minutes the MR measurement was repeated every 30 seconds. The images were independently evaluated by two investigators. Results: The improvement in quality after administration of secretin was statistically significant for both investigators (p < 0.05), but no significant difference was found between both investigators concerning the quality of the images (p = 0.49). Prior to the secretin application, the entire ductal system only be evaluated in ten cases (35.7%) by both investigators, afterwards in 26 cases (92.9%). Improvement was achieved after a mean time of 1.5 minutes and lasted until the ninth minute. Conclusion: Intravenous application of secretin improves image quality of MRCP also in patients with no pancreatic pathology. Improvement begins after 1.5 minutes and lasts for about seven minutes.