There is a close relationship between the biliary system and the duodenum and pancreas. The confluence of the common bile duct and the pancreatic duct often forms an enlarged potbelly, which is medically known as the Vater’s potbelly. It is about 1 to 3 cm long and opens in the duodenum, which is the “common channel” for the flow of bile and pancreatic juice. This small opening often affects one side when the other is sick, such as gallbladder stone drainage, common bile duct stone obstruction of the jugular opening, inducing cholangitis, obstructive jaundice, and even biliary acute pancreatitis. (As shown in the picture)