It is important to note that the pancreas originates from two separate embryonic buds, a dorsal bud and a ventral bud arising from the second part of the duodenum. The ventral bud arises in common with the primordium of the liver and biliary tract and eventually the ventral bud rotates behind the duodenum to fuse with the dorsal bud. The dorsal bud forms the bulk of the pancreas whilst the ventral bud gives rise to the uncinate process. Fusion of the ducts of the two buds leads to the formation of the main pancreatic duct. The last portion of the duct of the dorsal bud becomes the duct of Santorini or accessory pancreatic duct.

Structure and surgical anatomy of the pancreas

The pancreas gland lies at the back of the abdominal cavity, weighs approximately 80 - 100 gm and is approximately 20 cm long. It is divided into five parts. The head and uncinate process nestle with the curve of the duodenum, to the right of the spine. The neck of the pancreas lies in front of the superior mesenteric artery and vein, the gut vessels, which supply the whole of the small bowel, and these vessels are important factors in consideration of operability of pancreatic tumours. The body of the pancreas is triangular in cross-section and extends to the left side of the abdomen from the neck of the pancreas and leads into the tail of the gland. The tail of the pancreas lies over the left kidney and nestles in the hilum of the spleen. The pancreatic duct collects pancreatic juice made in the gland and runs from the tail of pancreas up to the head of the gland where it joins the second part of the duodenum. There are many variations in the blood supply to the pancreas.

Anatomy of the Pancreas

Schematic diagram of the liver, gallbladder and bile ducts - showing the location of the pancreas. © NDK - click to enlarge

L - liver
S - stomach
Sp - spleen
A - aorta
SpA - splenic artery
SpV - splenic vein
PV - portal vein
GB - gallbladder
MPD - main pancreatic duct
SI - small intestine
SMA - superior mesenteric artery
SMV - superior mesenteric vein
O - oesophagus
HA - hepatic artery
CBD - common bile duct
P - pancreas
D - duodenum
AM - ampulla
Pancreas - head
  - uncinate process
  - body
  - tail