The pancreas

Question 1

An organ of the digestive system as well as the endocrine system

Answer 1

• Functions as an exocrine and an endocrine gland

Question 2

Exocrine function

Answer 2

Secretes enzymes to break down proteins, lipids, carbs and nucleic acids in food

Question 3

endocrine function

Answer 3

Secretes insulin and glucagon to control blood sugar levels

Question 4

Embryology:

Answer 4

• Forms from two buds:
  Dorsal (DB) and ventral (VB) buds from primitive foregut
  Of endodermal origin
  DB and VB joins the foregut via a duct
• Duodenum rotates RHS
• VB comes to lie below and behind DB
• Parenchyma and main duct fuse = main duct
• VB = uncinate and inferior part of head
• DB= rest of head, body, tail, neck
• Main duct= DB origin (distal part)
• Accessory duct= DB origin (proximal part)

Question 5

Elongated accessory digestive gland that lies

Answer 5

retroperitoneally (except tail)

Question 6

Position

Answer 6

• Overlies and transversely cross the bodies of L1 and L2 (transpyloric plane)
• Lies post to stomach, between the duodenum on the right and the spleen on the left

Question 7

The pancreas is typically divided into five parts:

Answer 7

1. head
2. Uncinate process
3. Neck
4. Body
5. tail

Question 8

Head

Answer 8

– the widest part of the pancreas. It lies within the C-shaped curve created by the duodenum, and is connected to it by connective tissue. Contains the uncinate process.

Question 9

Uncinate process

Answer 9

– a projection arising from the lower part of the head and extending medially to lie beneath the body of the pancreas. It lies posterior to the superior mesenteric vessels.

Question 10

Neck

Answer 10

– located between the head and the body of the pancreas. It overlies the superior mesenteric vessels which form a groove in its posterior aspect.

Question 11

Body

Answer 11

– centrally located, crossing the midline of the human body to lie behind the stomach and to the left of the superior mesenteric vessels.

Question 12

Tail

Answer 12

– the left end of the pancreas that lies within close proximity to the hilum of the spleen. It is contained within the splenorenal ligament with the splenic vessels. This is the only part of the pancreas that is intraperitoneal.

Question 13

Arterial supply

Answer 13

• The body and tail of pancreas is mostly supplied by the pancreatic branches of the splenic artery. The head is additionally supplied by the superior and inferior pancreaticoduodenal arteries which are branches of the gastroduodenal (from coeliac trunk) and superior mesenteric arteries, respectively.
  Both sup and inf pancreaticoduodenal arteries divide into anterior and posterior branches that supply the head of the pancreas.

Question 14

Venous drainage

Answer 14

o Venous drainage of the head of the pancreas is into the superior mesenteric branches of the hepatic portal vein. The pancreatic veins draining the rest of the pancreas do so via the splenic vein/ superior mesenteric vein.

Question 15

Nerves:

Answer 15

Derived from the vagus and abdominopelvic splanchnic nerves that pass through the diaphragm.
The parasympathetic and sympathetic fibers reach the pancreas by passing along the arteries from the coeliac plexus and superior mesenteric plexus

Question 16

Lymphatic drainage:

Answer 16

The pancreas is drained by lymphatic vessels that follow the arterial supply.
They empty into the pancreaticosplenal nodes and the pyloric nodes. Efferent vessels from the pyloric nodes drain into the sup mesenteric and coeliac lymph nodes.