Biliary reflux detection in anomalous union of the pancreatico-biliary duct patients

AIM: To demonstrate the imaging findings of biliopancreatic and pancreatico-biliary reflux in patients with anomalous union of the pancreatico-biliary duct (AUPBD) on gadoxetic acid-enhanced functional magnetic resonance cholangiography (fMRC). METHODS: This study included six consecutive patients (two men and four women; mean age 47.5 years) with AUPBD. All subjects underwent endoscopic retrograde cholangiopancreatography (ERCP); one subject also underwent bile sampling of the common bile duct (CBD) to measure the amylase level because his gadoxetic acid-enhanced fMRC images showed evidence of pancreatico- biliary reflux of pancreatic secretions. Of the five patients with choledochal cysts, four underwent pylorus-preserving pancreaticoduodenectomy. RESULTS: The five cases of choledochal cysts were classified as Todani classification. In three of the six patients with AUPBD, injected contrast media reached the distal CBD and pancreatic duct on delay images, suggesting biliopancreatic reflux. In two of these six patients, a band-like filling defect was noted in the CBD on pre-fatty meal images, which decreased in size on delayed post-fatty meal images, suggesting pancreatico- biliary reflux of pancreatic secretions, and the bile sampled from the CBD in one patient had an amylase level of 113 000 IU/L. In one of the six patients with AUPBD, contrast media did not reach the distal CBD due to multiple CBD stones. CONCLUSION: Gadoxetic acid-enhanced fMRC successfully demonstrated biliopancreatic reflux of bile and pancreatico- biliary reflux of pancreatic secretions in patients with AUPBD with and without choledochal cysts.