Corpus: Pancreatic duct

The pancreatic duct is the excretory duct of the pancreas, which unites with the choledochal duct to form the ampulla hepatopancreatica and opens into the duodenum in the papilla duodeni major.

The pancreatic duct runs through the pancreas from the tail to the head. Along its course it receives inflows from the glandular ducts, which contain the pancreatic secretion with zymogens and bicarbonate. The zymogens are produced and secreted by the acinar cells, the bicarbonate by the duct cells (centroacinar cells). A distinction is made between intra- and interlobular ducts.

The pancreas arises from two sprouts of the enteroderm at the level of the duodenal loop. On the dorsal side of the duodenum, the dorsal pancreatic anlage grows into the mesoduodenum. The ventral pancreatic anlage forms somewhat later. Both anlagen have their own excretory ducts. However, the excretory duct of the larger dorsal pancreatic anlage usually fuses with the excretory duct of the smaller ventral pancreatic anlage to form the pancreatic duct (major).

Due to a lack of fusion of the ventral and dorsal pancreatic anlage during the embryonic period (pancreas divisum), an accessory duct of the pancreas may sometimes be present, the pancreatic duct minor (ductus Santorini). It originates from the dorsal pancreatic duct and usually opens into the duodenum via a separate papilla duodeni minor.

A further variation occurs when the pancreatic duct flows into the duodenum separately from the choledochal duct.

The diameter of the pancreatic duct should be a maximum of 2.5 mm on imaging, even in older patients.

See also: Gallstone, ERCP

• Image source podcast: Rayyu Maldives/ Unsplash
• Illustration: human gallbladder and biliary tree by www.sciepro.com; CC BY-ND 4.0 EN