Computed tomography under endoscopic retrograde pancreatography (ERP-CT) to investigate the drainage area of the pancreatic head.

The aim of this study was to evaluate the drainage area of the pancreatic head with computed tomography under endoscopic retrograde pancreatography (ERP-CT). ERP-CT was performed in 26 patients without lesions of the pancreatic head. By comparing ERP-CT images with ERP images, we evaluated the drainage area of the inferior branch of the pancreatic head. In 77% of these cases, the drainage function of Santorini's duct system (including the accessory papilla) was impaired. In 13 cases with the normal duct pattern, all inferior branches from Santorini's duct drained the anterior inferior area and all inferior branches from Wirsung's duct drained the posterior inferior area. In six cases with an ansa-type duct pattern, all inferior branches from Wirsung's duct drained the posterior inferior area, and inferior branches from Santorini's duct were divided into branches draining the anterior inferior area and branches draining the posterior inferior area. ERP-CT is a useful method for evaluating the three-dimensional anatomic variations of the pancreatic duct.