Chapter 7. DISEASES OF THE PANCREAS

ANATOMY OF THE PANCREAS

The pancreas is localized behind the peritoneum at the level of I-II lumbar vertebrae. Its length is 15-20 cm, width - 3-6 cm, thickness - 2-3 cm, average mass - 70-90 g. Parenchyma of the pancreas consists of multiple lobules separated from each other by connective tissue layers. Each lobule consists of epithelial cells forming acini.

There are distinguished the head, the body and the cauda of the pancreas. The head is surrounded by the 'horseshoe' of the duodenum. The body of the pancreas presents by its anterior surface to the posterior surface of the stomach and is separated from it by a narrow fissure - bursa omentalis. The posterior surface of the pancreas presents to the inferior vena cava, superior mesenteric vein, superior mesenteric artery, abdominal aorta; the inferior surface of the pancreas is contiguous with the duodenal inferior-horizontal ramus. Behind the pancreas at the meeting point of the head and the body of the gland there pass the superior mesenteric blood vessels, whole at the level of the superior border of the pancreas there passes the splenic artery in the direction of the gland's cauda.

The main (Wirsung's) duct is formed by means of fusion of minor lobular ducts. Its diameter is 0.5-5 mm.

Common bile duct and Wirsung's duct often form common ampule which opens into the major duodenal papilla. Sometimes the ampule is absent and the both ducts separately enter the duodenum.

The blood supply of the pancreas is provided by the branches of the pancreaticoduodenal artery (a. pancreaticoduodenalis) which supplies the major part of the head with blood. The branches of superior mesenteric

artery provide the blood supply of the head and the body, and the branches of the splenic artery (a. lienalis) - of the body and the cauda of the pancreas. The veins pass together with the arteries and enter the superior mesenteric and splenic veins through which the blood drains into the portal vein (v. porta).