›

Pancreas & Gallbladder

Notes

Pancreas & Gallbladder

Key organs of Biliary and Pancreatic Duct System:

  • Liver produces bile
  • Gallbladder stores and concentrates bile
  • Pancreas produces pancreatic juices
  • Duodenum receives bile and pancreatic juice, and mixes them with the contents of the GI tract.

pancreas

Key terms:

  • Duct is a small tube.
  • Ampulla is the dilated terminal end of the duct.
  • Sphincter is a circular muscle.
  • Papilla is a protuberance of target organ where the ampulla releases secretions.

Drainage Pathways:

  • Right, left, and common hepatic ducts drain bile from the liver; their function is reflected in their name, as "hepatic" refers to the liver.
  • Cystic duct carries bile to and from the gallbladder; it's helpful to know that "cystic" refers to the gallbladder (recall the "cystic" artery).
  • Bile duct receives bile from the cystic and common hepatic ducts, and delivers it to the duodenum. Notice that its name simply reflects its contents (bile), not a specific organ.
  • Main pancreatic duct drains pancreatic juice from pancreas
  • Main pancreatic and common bile duct merge at hepatopancreatic ampulla (regulated by hepatopancreatic sphincter)
  • Pancreatic juice and bile is drained into duodenum via major duodenal papilla.
  • When present, accessory pancreatic duct drains pancreatic juice into duodenum via minor pancreatic papilla.

Clinical correlations:

  • Post-hepatic jaundice (aka, obstructive jaundice) refers to the yellow staining of body tissues, including skin and mucous membranes; it is the result of accumulation of yellow bile pigments in the blood, and is a sign that bile is not exiting the gallbladder appropriately.
  • Gallstones, which are formed from crystalized bile, can become lodged within and obstruct the ducts of the biliary system, with serious health consequences.
    For example:
  • Cholecytitis (inflammation of the gallbladder) occurs when obstruction of the cycstic duct causes excessive bile accumulation in the gallbladder; subsequent swelling and irritation of the gallbladder can cause intense pain.
  • Pancreatitis (aka, pancreatic inflammation) can result from obstruction of the hepatopancreatic ampulla; instead of entering the small intestine, bile and pancreatic juices back up into the pancreas, causing inflammation.

Duct/Artery associations:

  • Cystic duct travels with the cystic artery
  • Right and left hepatic ducts travel with the right and left hepatic arteries
  • Common hepatic duct arises near the hepatic artery proper.

CT Scans

For more, see our Abdominal CT Scan Atlas on the Course Page