PANCREAS
Location and description
•The pancreas is an elongated, accessory digestive gland that lies retroperitoneally, overlying and transversely crossing the bodies of the L1 and L2 vertebra (the level of the transpyloric plane) on the posterior abdominal wall.
•It is soft and lobulated lies in the epigastrium and left upper quadrant.
•It lies posterior to the stomach between the duodenum on the right and the spleen on the left. The transverse mesocolon attaches to its anteroinferior margin.
Functions
•The exocrine portion of the gland produces a secretion that contains enzymes capable of hydrolyzing proteins, fats, and carbohydrates.
{acinar cells – pancreatic duct – duodenum}
•The endocrine portion of the gland, the pancreatic islets (islets of Langerhans), produces the hormones insulin and glucagon, which play a key role in carbohydrate metabolism.
{islets of Langerhans — blood }
Relations
•Anteriorly: From right to left—the transverse colon and the attachment of the transverse mesocolon, the lesser sac, and the stomach.
•Posteriorly: From right to left—the bile duct, the portal and splenic veins, the inferior vena cava, the aorta, the origin of the superior mesenteric artery, the left psoas muscle, the left suprarenal gland, the left kidney, and the hilum of the spleen
Parts of pancreas
The pancreas is divided into a head, neck, body, and tail.
•The head of the pancreas is disc shaped and lies within the concavity of the duodenum.
•A part of the head extends to the left behind the superior mesenteric vessels and is called the uncinate process. It extends medially, inferiorly and backwards.
•Bile duct is embedded into the posterosuperior part of the head.
•The neck is the constricted portion of the pancreas and connects the head to the body.
• It lies in front of the beginning of the portal vein and
•The origin of the superior mesenteric artery from the aorta forms a groove on its posterior surface. It lies at the transpyloric plane.
•The body runs upward and to the left across the midline. It is somewhat triangular in cross section.
•Antero inferior part of the body gets the attachment of the root of transverse mesocolon.
•It crosses left renal vein, aorta, SMA, left crux of diaphragm, left psoas, left supra renal and kidney.
•Splenic artery passes along its upper border
•It forms the stomach bed and floor of omental bursa
•The tail passes forward in the splenorenal ligament and comes in contact with the hilum of the spleen.
•Splenic vessels also pass with it in the splenorenal ligament.
Pancreatic ducts
•The main pancreatic duct (of wirsung) begins in the tail of the pancreas and runs through the parenchyma of the gland to the pancreatic head.
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•The main pancreatic duct and bile duct usually 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.
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•The end of the bile duct, pancreatic duct and the ampulla of vater are surrounded by smooth muscle sphincters to control the flow of bile and pancreatic juice into the duodenum. The sphincter around the ampulla is called hepatopancreatic sphincter of Oddi.
•The accessory duct of the pancreas, when present, drains the upper part of the head and then opens into the duodenum a short distance above the main duct on the minor duodenal papilla. The accessory duct frequently communicates with the main duct
Lymphatic drainage
Nerve supply
spleen
•The spleen is an ovoid, usually purplish, pulpy mass about the size and shape of one’s fist.
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•It is relatively delicate and considered the most vulnerable abdominal organ. It is the largest single mass of lymphoid tissue in the body.
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•It is not a component of the GI tract, despite their close relationship
location
•The spleen is located in the superolateral part of the left upper quadrant (LUQ), or hypochondrium of the abdomen, where it enjoys protection of the inferior thoracic cage.
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•It lies just beneath the left half of the diaphragm close to the 9th, 10th, and 11th ribs. The long axis lies along the shaft of the 10th rib, and its lower pole extends forward only as far as the midaxillary line and cannot be palpated on clinical examination
Functions
•Prenatally, the spleen is a hematopoietic (blood-forming) organ, but after birth it is involved primarily in identifying, removing, and destroying expended red blood cells (RBCs) and broken-down platelets, and in recycling iron and globin.
•The spleen serves as a blood reservoir and can restore RBCs and platelets in case of hemorrhage.
•The spleen is a soft, vascular, sinusoidal mass with a relatively delicate fibroelastic capsule.
•The thin capsule is covered with a layer of visceral peritoneum that entirely surrounds the spleen except at the splenic hilum, where the splenic branches of the splenic artery and vein enter and leave.
•The peritoneum also passes to the left kidney as the splenorenal ligament (carrying the splenic vessels and the tail of the pancreas).
RELATIONS
•Anteriorly: The stomach, tail of the pancreas, and left colic flexure. The left kidney lies along its medial border.
•Posteriorly: The diaphragm, left pleura (left costodiaphragmatic recess), left lung, and 9th, 10th, and 11th ribs.
•Inferiorly: The left colic flexure.
•Medially: The left kidney.
GROSS FEATURES
It has two surfaces and two borders:
The anterior and superior borders of the spleen are sharp and often notched,
whereas its posterior end and inferior border are rounded
Diaphragmatic surface:
Is convexly curved to fit the concavity of the diaphragm and curved bodies of the adjacent ribs.
Visceral surface:
Has impressions of left kidney posteriorly, stomach anteriorly and left colic flexure inferiorly.
At the hilum, the spleen contacts the posterior wall of the stomach and is connected to its greater curvature by the gastrosplenic ligament, and to the left kidney by the splenorenal ligament.
The splenorenal ligament, contains splenic vessels and the tail of pancreas. Between its layers the splenic artery divides into five or more branches that enter the hilum.
Blood supply
Lymphatic drainage
clinicals
•Blockage of Hepatopancreatic Ampulla and Pancreatitis
•Pancreatic pseudocyst
•Endoscopic Retrograde Cholangiopancreatography
•Pancreatectomy
•Pancreatic Cancer
•Pancreatic tail and splenectomy
•Rupture of Spleen
•Splenectomy and Splenomegaly