Chapter 16: The Pancreas

Superior Mesenteric Vein

Along with tributaries of the splenic vein, serves as venous drainage for the pancreas.

Splenic Vein

Along with tributaries of the superior mesenteric vein, serves as the venous drainage for the pancreas.

Portal Splenic Confluence

Area just posterior to the neck of the pancreas, where the splenic vein meets the superior mesenteric vein. Together, these veins form the portal vein.

Pancreaticoduodenal Arteries

Arteries that supply the head of the pancreas and part of the duodenum with blood. Part of the pancreatic arcades.

Pancreatic Body

Bordered right laterally by the pancreas neck, left laterally by the pancreas tail, anteriorly by the posterior wall of the stomach, and posteriorly by the splenic vein. Considered the largest portion of the pancreas.

Alpha Cells

Cells that account for 15% to 20% of pancreatic endocrine tissue and produce the hormone glucagon.

Delta Cells

Cells that account for approximately 5% of pancreatic endocrine tissue that produces the hormone somatostatin.

Epsilon Cells

Cells that account for less than 1% of pancreatic endocrine cells, and produce the hormone ghrelin, which may affect blood sugar regulation.

Pancreatic Juice

Composed of enzymes porduced by acini cells in the pancreas that help digest fats, proteins, carbohydrates, and nucleic acids.

Beta Cells

Constitute 60% to 70% of the pancreatic endocrine cells that produce insulin.

Ampulla of Vater

Dilatation in the second portion of the duodenum, where the common bile duct and pancreatic duct(s) enter to discharge substances that aid in the digestive process.

Common Bile Duct (CBD)

Distal portion of the biliary tract that transposts and then discharges bile (that was manufactured in the liver) into the duodenum as needed to aid the digestive process.

Suprapancreatic Splenic Artery

First 3-cm section of the artery as it originates from the celiac axis.

Gastroduodenal Artery

First branch of the common hepatic artery. Courses along the anterolateral aspect of the pancreas head just right lateral to the pancreas neck, where it divides into anterior and posterior superior pancreaticoduodenal branches. Supplies blood to the head of the pancreas and the duodenum.

Portal Vein

Formed by the confluence of the splenic vein and the superior mesenteric vein just posterior to the neck of the pancreas.

Islets of Langerhans

Groups of alpha, beta, and delta endocrine cells in the pancreas that produce insulin.

Glucagon

Hormone produced by alpha cells in the pancreas that causes the release of glucose to meet the immediate energy needs of the body.

Insulin

Hormone produced by beta cells in the pancreas that causes glycogen formation from glucose in the liver.

Somatostatin

Hormone produced by the delta cells in the pancreas that inhibits the production of insulin and glucose.

Pancreatic Tail

Left lateral to the pancreas body and aorta and extends to the hilum of the spleen. Situated between the stomach anteriorly and left kidney posteriorly. The splenic vein runs along its posterosuperior surface. May lie higher, lower, or on an even level with the body.

Pancreatic Head

Lies right lateral to the superior mesenteric vein; cradled in the C-loop of the duodenum; directly anterior to the inferior vena cava.

Duct of Wirsung

Main pancreatic duct. Transports and discharges pancreatic juice into the duodenum through the ampulla of Vater to aid the digestive process.

Sphincter of Oddi

Muscle surrounding the ampulla of Vater that controls the flow of pancreatic juice from the pancreas and bile from the biliary tract into the duodenum.

Gamma Cells

Pancreatic Polypeptide (Pp) cells that comprise less than 5% of pancreatic endocrine cells and may affect blood sugar regulation.

Duct of Santorini

Pancreatic accessory duct that enters the duodenum approximately 2 cm superior to the duct of Wirsung.

Uncinate Process

Posteromedial projection of the pancreas head that lies directly posterior to the superior mesenteric vein and directly anterior to the inferior vena cava or in some cases, due to its size, the abdominal aorta.

Acini Cells

Produce pancreatic juice that is composed of enzymes to help digest fats, proteins, carbohydrates, and nucleic acids.

Endocrine

Produces and secretes hormones directly into the bloodstream with a ductal system.

Exocrine

Produces and transports pancreatic juice via ducts to aid in digestion.

Prehilar Splenic Artery

Section of the artery before it enters the hilum of the spleen.

Prepancreatic Splenic Artery

Section of the artery before it leaves the pancreas.

Pancreatic Splenic Artery

Section of the artery located within the pancreas.

Pancreatic Neck

Situated between the pancreatic head and body immediately anterior to the superior mesenteric vein. At a slightly higher level, it lies anterior to the portal splenic confluence.

Splenic Artery

Supplies the body and tail of the pancreas with blood. From its origin at the celiac axis, it runs along the superior edge of the pancreas body and tail parallel to the splenic vein.

Pancreatic Arcades

Vascular connections between the pancreaticoduodenal, hepatic, splenic, and superior mesenteric arteries that supply blood to the head of the pancreas.