E2C Flashcards
Stomach, liver, biliary ducts, spleen, and celiac trunk
stomach
dilated part of alimentary canal located in left hypochondriac, epigastric and umbilical regions much of it lies under cover of lower ribs and costal cartilages
functions: stores food, mixes food with gastric secretions to form semi-fluid mass (chyme), controls rate of delivery of chyme to small intestine
stomach surfaces/borders
2 surfaces (walls): anterior and posterior 2 borders: lesser curvature (shorter and on the right) and greater curvature (longer and on the left)
incisura angularis (angular notch): indentation located in lower part of lesser curvature
stomach orifices
cardial orifice: communicates esophagus with stomach
cardial notch: indentation located between left border of esophagus and fundus of stomach
pyloric orifice: communicates stomach with duodenum it is surrounded by a sphincter (pyloric sphincter), formed by a thickening of circular muscle layer of stomach
stomach parts
cardia (cardial part): area immediately adjacent to cardial orifice
fundus: dome-shaped, upper part of stomach; limited inferiorly by horizontal line drawn across stomach starting at cardial notch; usually is full of gas
body: extends from level of cardial notch to level of angular notch
pyloric part: distal, funnel-shaped region of stomach; extends from angular notch to pyloric orifice; its proximal, wider part is known as pyloric antrum; its distal, narrower part is known as pyloric canal
stomach anatomical relations
anteriorly: anterior abdominal wall, left costal margin, diaphragm, left lobe of liver
posteriorly: lesser sac, diaphragm, spleen, upper part of left kidney, left suprarenal gland, splenic artery, pancreas, transverse mesocolon
abdominal aorta
begins at the level of T12 (aortic hiatus of diaphragm) as a continuation of descending thoracic aorta descends anterior to lumbar vertebral column, posterior to peritoneum (it is a retroperitoneal structure), and to the left of IVC; terminates at level of L4 by dividing into right and left common iliac arteries
abdominal aorta visceral branches
unpaired: celiac trunk, superior mesenteric artery, inferior mesenteric artery
paired: middle suprarenal arteries, renal arteries, testicular/ovarian arteries
abdominal aorta parietal branches
unpaired: median sacral artery
paired: inferior phrenic arteries, lumbar arteries (4 pairs)
celiac trunk
originates from abdominal aorta at the level of T12; lies posterior to stomach and lesser sac
immediately divides into 3 branches:
left gastric artery
splenic artery
common hepatic artery
left gastric artery
smallest branch of celiac trunk; passes superiorly and to the left, toward cardial region of stomach, posterior to lesser sac
gives off esophageal branches (supply lower part of esophagus) and then descends along lesser curvature of stomach
anastomoses with right gastric artery
splenic artery
largest branch of celiac trunk; runs to the left along superior border of pancreas, posterior to stomach and lesser sac (it follows a wavy course); reaches hilum of spleen within splenorenal ligament
branches of splenic artery
pancreatic branches: supply neck, body and tail of pancreas
left gastroepiploic artery: originates near hilum of spleen reaches greater curvature of stomach in gastrosplenic ligament and runs along greater curvature from left to right; anastomoses with right gastroepiploic artery
short gastric arteries: originate close to hilum of spleen; reach stomach in gastrosplenic ligament and supply its fundus
terminal branches: enter spleen through its hilum
common hepatic artery
runs anteriorly and to the right to reach superior aspect of 1st part of duodenum, where it divides into 2 branches: proper hepatic artery and gastroduodenal artery
proper hepatic artery
ascends between 2 layers of lesser omentum (hepatoduodenal ligament) toward hilum of liver (porta hepatis); divides into right and left branches that enter liver through porta hepatis; right branch usually gives off cystic artery (supplies gallbladder)
within lesser omentum, proper hepatic artery lies anterior to portal vein and to the left of common bile duct
right gastric artery
usually originates from proper hepatic artery; descends to pyloric end of stomach; runs to the left along lesser curvature of stomach; anastomoses with left gastric artery
gastroduodenal artery
descends posterior to 1st part of duodenum; it gives off right gastroepiploic and superior pancreaticoduodenal arteries
right gastroepiploic artery
runs along greater curvature of stomach from right to left; anastomoses with left gastroepiploic artery
superior pancreaticoduodenal arteries
anterior and posterior
supply duodenum and head of pancreas; anastomose with inferior pancreaticoduodenal arteries (branches of superior mesenteric artery)
stomach blood supply
arteries:
left gastric artery (branch of celiac trunk)
right gastric artery (branch of proper hepatic artery)
left gastroepiploic artery (branch of splenic artery)
right gastroepiploic artery (branch of gastroduodenal artery)
short gastric arteries (branches of splenic artery)
all arteries are accompanied by veins of same name all venous blood from stomach drains (directly or indirectly) into portal vein
liver
located in upper part of abdominal cavity, just beneath diaphragm, in right hypochondriac, epigastric and left hypochondriac regions; most of it lies under cover of lower ribs and costal cartilages
liver surfaces
diaphragmatic and visceral surfaces are separated anteriorly by a sharp border (inferior border of liver): no clear demarcation between them posteriorly
diaphragmatic surface
convex, smooth, molded to undersurface of diaphragm
visceral surface
faces inferiorly, posteriorly and to the left: molded to adjacent organs (gallbladder, esophagus, stomach, duodenum, right kidney, right suprarenal gland, right colic flexure); visceral surfaces “H”
cross bar of H
porta hepatis (hilum of liver): contains right and left hepatic ducts (collect bile produced by liver), branches of proper hepatic artery and portal vein (supply blood to liver), autonomic nerves and hepatic lymph nodes and vessels
right limb of H (right sagittal fissure)
formed anteriorly by fossa for gallbladder and posteriorly by groove for IVC
left limb of H (left sagittal fissure)
formed anteriorly by fissure for round ligament of liver (ligamentum teres hepatis) and posteriorly by fissure for ligamentum venosum
liver embryology
during intrauterine life, umbilical vein carries oxygenated blood from placenta umbilical vein joins portal vein a large proportion of this blood bypasses liver and goes directly into IVC via ductus venosus
at birth, umbilical vein and ductus venosus close and become fibrous cords umbilical vein becomes round ligament of liver and ductus venosus becomes ligamentum venosum
quadrate lobe of liver
part of liver located anterior to porta hepatis, between fossa for gallbladder (right) and fissure for round ligament (left)
caudate lobe of liver
part of liver located posterior to porta hepatis, between groove for IVC (right) and fissure for ligamentum venosum (left)
liver peritoneal ligaments
falciform
coronary
R/L triangular
lesser omentum
falciform ligament
two-layered peritoneal fold that connects diaphragmatic surface of liver to anterior abdominal wall (above umbilicus); its liver attachment forms boundary between right and left lobes; has an inferior, free margin that contains round ligament of liver; posteriorly its 2 layers separate and become superior layer of coronary ligament
coronary ligament
consists of superior and inferior layers, which lie at some distance from each other; between them there is an area of liver devoid of peritoneum that is in direct contact with diaphragm; bare area of liver
right and left triangular ligaments
right and left ends of coronary ligament, where its superior and inferior layers join each other
lesser omentum
two-layered peritoneal fold that connects visceral surface of liver (porta hepatis and fissure for ligamentum venosum) to lesser curvature of stomach and 1st part of duodenum
liver blood ciruclation
30% from proper hepatic artery, 70% from portal vein
artery and vein divide into progressively smaller branches; eventually arterial and venous blood mix in liver capillaries (sinusoids); blood is collected afterward by hepatic veins
hepatic veins join forming progressively larger veins; eventually 3 large hepatic veins are formed (right, intermediate [middle] and left) which drain into IVC
extra hepatic biliary ducts
bile produced by hepatocytes is collected by small bile ducts within liver; these ducts join to form progressively larger ducts
eventually, 2 large ducts are formed (right and left hepatic ducts), which exit liver via porta hepatis; after a short course, right and left hepatic ducts join to form common hepatic duct
common hepatic duct
common hepatic duct descends within hepatoduodenal ligament and is joined by cystic duct (from gallbladder) to form common bile duct
common bile duct
lies first within hepatoduodenal ligament, then it passes posterior to 1st part of duodenum, and more inferiorly it lies posterior to head of pancreas (or embedded in it)
usually joined by main pancreatic duct; they form a short dilated chamber embedded in duodenal wall (hepatopancreatic ampulla or ampulla of Vater), which opens into 2nd part of duodenum by an orifice on the tip of a small mucosal elevation (major duodenal papilla)
hepatopancreatic ampulla
surrounded by a sphincter (sphincter of hepatopancreatic ampulla or sphincter of Oddi)
gallbladder parts
fundus: anterior, rounded end which projects below inferior border of liver it is in contact with anterior abdominal wall at level of tip of right 9th costal cartilage
body: middle part of gallbladder (between fundus and neck); contacts visceral surface of liver (superiorly) and transverse colon and duodenum (inferiorly)
neck: narrow, tapering end, opposite the fundus and directed toward porta hepatis usually makes and S-shaped bend and becomes continuous with cystic duct
spleen
largest lymphoid organ of the body; located in left hypochondriac region, between stomach and diaphragm, entirely sheltered by lower ribs (9th to 11th); lacerations of spleen are commonly caused by fractured ribs
spleen functions
elimination of old and/or damaged blood cells
filters antigens from blood and contributes to immune response against such antigens
spleen surfaces
diaphragmatic: smooth and convex, faces posterolaterally, related to diaphragm
visceral: irregular and concave, faces anteromedially, related to stomach, left kidney, left colic flexure and tail of pancreas, also contains hilum of spleen
spleen borders
borders: superior (usually notched) and inferior
poles: anterior and posterior
long axis of spleen lies along 10th rib
normal spleen cannot be palpated in the adult (anterior pole reaches normally as far forward as midaxillary line)
spleen ligaments
intraperitoneal organ: its hilum is connected to stomach and left kidney by gastrosplenic and splenorenal ligaments, respectively
splenorenal ligament contains splenic artery and vein and tail of pancreas
gastrosplenic ligament contains short gastric arteries and veins and left gastroepiploic artery and vein
spleen blood supply
splenic artery (branch of celiac trunk) venous drainage: splenic vein, begins at hilum of spleen and runs to the right, inferior to splenic artery, and posterior to pancreas; drains into portal vein
