Anatomy of the Foregut Organs Flashcards
3 main arteries in the gut and what area do they supply
Celiac artery (foregut)
Superior mesenteric artery (midgut)
Inferior mesenteric artery (hindgut)
Foregut derivatives in the abdomen
Abdominal esophagus
Stomach
Duodenum (proximal to the opening of the bile duct)
Liver
Biliary apparatus (hepatic duct, gallbladder, bile duct)
Pancreas
Where does the midgut become the hindgut
Halfway through transverse colon
What vertebral level does the esophagus
- Enter through diaphragm
- Join to esophagus
- T10
2. T11
Parts of the stomach
Cardiac and pyloric openings Greater and lesser curvature Anterior and posterior surfaces Fundus (usually distended with gas) Body Pyloric antrum and canal Cardiac (or LES) and pyloric sphincters
Gastric canal
Longitudinal rugae along the lesser curvature of the stomach make canals for passing liquids to the lower part of the stomach
Can lubricate solid food
Greater omentum
Fold of peritoneum that hangs from the greater curvature of the stomach
Contains fat, blood vessels, nerve fibers, and lymphatic nodes
Lesser omentum
Fold of peritoneum that extends from the lesser curvature of the stomach and the first 2 cm of duodenum to the liver
Epiploic foramen (foramen of Winslow)
Behind the free border of the lesser omentum
Connects the lesser sac to the greater sac
2 parts of the lesser omentum
Hepatogastric ligament
Hepatoduodenal ligament
Hepatoduodenal ligament
Contains the portal vein, hepatic artery, and bile ducts
Duodenum
Shortest, widest and most fixed part of the small intestine
C shaped
Curves around the head of the pancreas
4 parts of the duodenum
Superior part: anteriorly, related to the gallbladder
Descending: here you can see the major and minor duodenal papillae
Inferior: Anteriorly is related to the superior mesenteric vessels
Ascending: terminates at the duodenojejunal flexure
Major duodenal papilla
Mucosal elevation and the hepatopancreatic ampulla opens at the summit
In the second (descending) part of the duodenum
4 parts of the pancreas
Head
Neck
Body
Tail
What regions of the abdomen does the liver occupy?
Entire R hypochondriac and epigastric regions
Extends into the L hypochondriac
Falciform ligament
Divides liver into L and R lobes
Fold of peritoneum that attaches it to the abdominal wall (weight support)
Doesnt carry blood supply
4 lobes of the liver
Right
Left
Caudate (posterior)
Quadrate (anterior)
Porta hepatis
Located between the quadrate and caudate lobes
Contains the portal vein, hepatic artery, and hepatic plexus of nerves (enter) and the R and L hepatic ducts (leave)
3 things: hepatic artery, portal vein, bile passages
Round ligament of liver
At the bottom of the falciform ligament
Contains the obliterated umbilical vein
Extends from the umbilicus to the liver
Bare area
Small triangular area on the posterior surface of the liver that has not been covered by peritoneum
Passage of bile
Right and left hepatic ducts join to form common hepatic duct
Joins with cystic duct to form common bile duct
Joins with major pancreatic duct to form hepatopancreatic ampulla
Spleen
Wedge shaped organ in the L hypochondriac region
Superior border is notched
Derived from mesoderm, but blood supply from celiac trunk
Can get splenomegaly or trauma
Celiac artery (trunk)
Foregut artery and one of the major branches of the abdominal aorta
Arises at the level of T12 (L1 disc)
3 branches: left gastric, common hepatic, splenic
Portal vein
Large vein that collects blood from the Gi tract and its associated glands (and spleen) and conveys it to the liver
What makes up the portal vein?
The splenic vein and the inferior mesenteric vein join, and then join with the superior mesenteric vein to become the portal vein
Splanchnic nerves
Don’t synapse in the sympathetic chain!!
Synapse in the celiac, superior/inferior mesenteric ganglia
T5-T9 form the greater splanchnic nerve
Innervation of the foregut organs
Celiac ganglia
Sympathetic input comes from the greater splanchnic nerves (T5-T9)
Parasympathetic input comes from the vagus nerve
Distribution of the post-gang symp and pregang parasymp is done by the arteries
Referred pain from the foregut organs is normally felt where? Why?
Epigastric region
Pain fibers travel with sympathetic nerves, they come from T5-T9 and enter in the epigastric region
Cisterna chyli (Chyle cistern)
Elongated lymphatic sac in front of L1/L2 vertebrae
Drains lymph from the lower limbs, pelvis, and posterior abdominal wall organs into the cisterna chyli
Upper end is continuous with the thoracic duct
Marginal artery is formed by the fusion of…
Superior and Inferior mesenteric arteries
