Pancreas Flashcards
Talk about pancreas ?
1- elongated organ
2- accessory digestive gland
3- mixed gland as
• it has exocrine secretion ( pancreatic juice by acinar cells that goes to duodenum through main and accessory pancreatic duct )
• endocrine secretion ( insulin, glucagon by islet cells of langerhans to blood directly)
Parts of pancreas ?
Head : the widest part , embeded in c curve of duodenum
Uncinate process
Neck : the constricted part
Body : tapering to the left slightly elevated
Tail : tapering end near the spleen
Location of pancreas
It is retro peritoneal, behind the stomach located on the posterior abdominal wall between the duodenum on the right to the spleen on the left
Talk about the head
1- embedded in the c curve duodenum to the right of the splenic vessels
2- firmly attached to medial aspect of the descending and horizontal duodenum
3- it rests posteriorly on IVC
4- on its way to open in the descending duodenum ,the common bile duct located in a groove on posterosuperior surface of head or embeded in its substances
Ralations of the neck
• related posteriorly to sm vessels and beginning of portal vein ( splenic vein + smv)
• anterior surface of neck covered with peritoneam adjacent to the pylorus of stomach
Talk about the body ( borders and surfaces)
1- it has 3 borders : inf , ant and post
And has 3 surfaces inf , ant and post
• upper border : related to celiac trunk and splenic artery
• anterior border : give attachment to the transverse mesocolon
• anterior surface : posterior to stomach
• inferior surfaces: related to coils of small intestine and transverse colon
• posterior surface : devoid of peritoneam and related to 2 arteries ( sma and aorta )
2 veins ( splenic vein and left renal )
2 glands ( left kidney and suprarenal )
2 muscles ( left psoas major ,diaphragm)
Sympathetic chain
Sma has a double relation to pancreas
As it pass behind the body and then pass in front of thr uncinate process
Relations of the tail
Lies anterior firmly to left kidney where it is so close to it and splenic hileum
Passes in splenorenal ligament
Talk about pancreatic ducts
The main pancreatic ( duct of wirsung)
It begins in the tail of the pancreas and runs through the parenchyma of the gland to the pancreatic head, here it turns inferiorly and is closely related to the bile duct.
The main pancreatic duct and the bile duct unite to form the short,dilated hepatopancreatic ampulla (of vater), which opens into the
descending part of the duodenum at the summit of the major duodenal
papilla.
Accessory pancreatic duct ( duct of santorini)
It drains the upper part of the head. it opens into the duodenum at the summit of the minor duodenal papilla. Usually (60%) communicates with the main pancreatic duct.
Blood supply of pancreas
Arterial
-The pancreatic arteries derive mainly from the branches of the splenic artery and supply the body and tail of pancreas
-The anterior and posterior superior pancreaticoduodenal arteries,
branches of the gastroduodenal artery
-The anterior and posterior inferior pancreaticoduodenal arteries,
branches of the SMA
Venous
The pancreatic veins: superior drain into portal vein, inferior drain into superior mesenteric vein and pancreatic veins drain to splenic vein.
Lymphatic drainage of pancreas
The pancreatic lymphatic vessels follow the blood vessel. Most of them end in the pancreaticosplenic nodes that lie along the splenic artery, but some vessels end in the pyloric lymph nodes. Efferent vessels
from these nodes drain to the superior mesenteric lymph nodes or to the
celiac lymph nodes via the hepatic lymph nodes.
Development of pancreas
1-It develops from ventral and dorsal buds originating from endodermal lining of duodenum.
2-Dorsal bud is located short distance above ventral bud.
3-Ventral bud arises in common with hepatic bud close to junction of foregut with midgut.
4-As the duodenum rotates to right and becomes C- shaped the ventral
pancreatic bud migrates dorsally. It lies immediately below and behind dorsal pancreatic bud.
5-Then, parenchyma and duct system of ventral and dorsal buds fuse together.
6-Ventral bud forms uncinate process and inferior part of head of pancreas.
7-Dorsal bud forms the remaining part of pancreas.
8-The main pancreatic duct is formed by distal part of dorsal pancreatic duct and the whole ventral pancreatic duct.
9-Proximal part of dorsal pancreatic duct is obliterated or persists as accessory pancreatic duct.
10-Main pancreatic duct and common bile duct enters duodenum at major
papilla. While accessory pancreatic duct enters it at site of minor papilla.
11 -Islets of Langerhans are proliferated epithelial cells which become separated from duct system.
Congenital anomalies of pancreas
1-Annular pancreas; it occurs because the ventral pancreatic bud is
formed of two parts: Right portion migrate normally. While Left portion migrates in opposite direction
2- Accessory pancreatic tissue:
May be found in mucosa of stomach, gall bladder and spleen
