Upper GI Tract Flashcards
What structure divides the abdominal cavity from the pelvic cavity?
This is a trick question, there is no separation. The two cavities are continuous.
What diaphragms serve as the boundaries of the abdominalpelvic cavity?
Superiorly-the respiratory diaphragm
Inferiorly- the pelvic diaphragm
Describe the imaginary plane that separates the abdominal cavity from the pelvic cavity.
The imaginary plane is drawn from the superior anterior portion of the sacrum to the pubis anteriorly.
What 3 important structures are transmitted through diaphragmatic hiatuses?
- Inferior Vena cava (8)
- Aorta (12)
- Esophagus (10)
What other 2 structures may also pass through the aortic hiatus at vertebral level T12?
- The thoracic duct
2. Azygous vein
Mnemonic: I ate 10 eggs at 12
This mnemonic helps you remember the vertebral level at which specific structures pass through their diaphragmatic hiatus to enter the abdominal cavity.
I 8: inferior vena cava @T8
10 Eggs: esophagus @ T10
At 12: aorta @T12
What is the name for the small arteries that travel along the inferior surface of the diaphragm and contribute to the blood supply of the diaphragm?
Inferior phrenic arteries
If you open the abdominal wall from an anterior view, what structures would you see?
- Liver
- Stomach
- A small portion of the small intestine
- Greater omentum
What layer of peritoneum covers the organs in the peritoneal cavity?
Visceral peritoneum
Where would the parietal peritoneum of the peritoneal cavity be located?
Parietal peritoneum can be found covering the internal aspect of the abdominal wall.
When you remove the abdominal wall, containing the parietal peritoneum, and view the abdominal structures, covered by visceral paritoneum, what space is being examined (the answer is NOT the abdominal cavity)?
Peritoneal cavity.
The peritoneal cavity is dividing into two different spaces, what are they?
- Greater sac
2. Lesser sac
Where is the greater sac of the peritoneal cavity?
The greater sac is the area that lies on top of AND under the greater omentum.
If you remove the greater omentum and placed your hand on top of the colon or small intestine, is your hand still located in the greater sac?
Yes, the colon is also covered by visceral peritoneum. This, if your hand is under the greater omentum but still on top of the colon you are still within the greater sac of the peritoneal cavity.
Where is the lesser sac of the peritoneal cavity located? What is it’s function?
The lesser sac is located posterior to the stomach.
The lesser sac is an area into which the stomach may expand.
Which omentum is associated with the greater curvature of the stomach?
Greater omentum
Which omentum is associated with the lesser curvature of the stomach?
Lesser omentum
The lesser omentum lies between which two organs?
Stomach (attached to the lesser curvature) and the liver
Name the opening on the right border of the lesser omentum that grants access to the space posterior to the stomach (lesser sac).
Epiploic foramen (aka foramen of Winslow)
What is the alternative name for the foramen of Winslow?
Epiploic foramen
What is the alternative name for the epiploic foramen?
Foramen of Winslow
What three structures does the peritoneum form?
- Visceral pleura
- Parietal pleura
- Mesenteries (two layers of peritoneum)
What are the characteristic features of mesenteries?
- Formed by two layers of peritoneum
2. Contain neurovascular structures for the organs they are associated with
What other structures are considered mesenteries here at UCLA?
- Ligament
- Greater omentum
- Lesser omentum
What are the requirements for naming an abdominal structure “peritoneal”?
- The structure must have a named mesentery
2. It must be covered by peritoneum on more than one surface
What are the requirements for a structure to be considered “retroperitoneal”?
- It does not have a named mesentery.
2. There is not a peritoneum on more than one surface
Do retroperitoneal structures need mesenteries?
No. This structures grow right on top of the posterior abdominal wall (pancreas) or on the lateral part of the abdominal wall (ascending and descending colon). Their neurovascular supply can reach them from behind.
Stomach, Liver, transverse colon. Are these structures peritoneal or retroperitoneal?
Peritoneal.
Stomach & liver: surrounded by peritoneum and has named mesentery (hypogastric ligament and greater omentum
Transverse colon: peritoneum and mesentery
Pancreas, ascending colon, descending colon. Retroperitoneal or peritoneal?
Retroperitoneal.
These structures do not need a mesentery as their neurovascular supply can reach them from behind the peritoneum
Where is the pancreas?
Behind the peritoneum, just anterior to the aorta and vena cava.
What six mesenteries are we responsible for knowing here at UCLA?
- Greater omentum
- Lesser omentum
- The Mesentery
- Mesoappendix
- Transverse mesocolon
- Sigmoidal mesocolon
What is an alternative name for the greater omentum?
Gastrocolic ligament
How many layers can the greater omentum have? Why is this?
4 layers because it extends from the inferior portion of the stomach and then turns up superiorly to travel to the colon.
Does the greater omentum always have 4 layers?
No. At some portions there are only two layers as is characteristic of a traditional mesentery.
Name the two subligaments of the lesser omentum.
- Hepatogastric ligament
2. Heptoduodnal ligament
What structures does the lesser omentum attach to?
Stomach, liver and first part of the small intestine (duodenum)
If you lift the greater omentum and pull the small intestine anteriorly, what three mesenteries have you uncovered?
- The Mesentery
- Mesoappendix
- Transverse mesocolon
Which mesentery is barely visible and contains neurovasculature that serves the appendix?
Mesoappendix
Which mesentery contains the most neurovasculature that serves the small intestine?
The Mesentery
Which mesentery contains neurovasculature that serves the transverse colon?
Transverse mesocolon
Which mesentery serves the ascending colon?
Trick question: The ascending and descending mesocolon DO NOT have named mesenteries. These structures receive their neurovascular supply from behind the peritoneum. They are retroperitoneal.
If you remove the greater omentum, and completely remove all of the small intestine, which mesentery had been uncovered?
Sigmoid mesocolon
Which mesentery serves the descending colon?
Trick question: The ascending and descending mesocolon DO NOT have named mesenteries. These structures receive their neurovascular supply from behind the peritoneum. They are retroperitoneal structures.
Which mesentery contains neurovascular structures that serve the sigmoid colon?
Sigmoid mesocolon
Name the 3 subdivisions of the gut tube?
- Foregut
- Midgut
- Hindgut
How are the three divisions of the gut tube supplied with blood and innervated?
Each division has it’s own large aortic branch to supply blood and it’s own visceral plexus to supply autonomic innervation.
What is the major aortic branch and nerve supply for the foregut?
Celiac trunk; celiac plexus
What structures comprise the foregut?
Stomach, duodenum (first two segments)
What associated organs comprise the foregut?
Liver, gallbladder, pancreas(also shared with midgut), spleen abdominal esophagus (blood suppy only)
Which mesentery contains the most neurovasculature and serves the small intestine?
The Mesentery
Which mesentery is barely visible and contains neurovasculature that serves the appendix?
Mesoappendix
Which mesentery contains the neurovasculature that serves the transverse colon?
Transverse mesocolon
Which mesentery serves the ascending colon?
Trick question: The ascending and descending mesocolon DO NOT have named mesenteries. These structures receive their neurovascular supply from behind the peritoneum.
Which mesentery serves the descending colon?
Trick question: the ascending and descending mesocolon DO NOT have named mesenteries. These structures receive their neurovascular supply from behind the peritoneum. They are retroperitoneal structures.
If you remove the greater omentum, and completely remove all of the small intestine, which mesentery had been uncovered?
Sigmoid mesocolon
Which mesentery contains neurovascular structures that serve the sigmoid colon?
Sigmoid mesocolon
Name the 3 subdivisions of the gut tube?
- Foregut
- Midgut
- Hindgut
How are the three divisions of the gut tube supplied with blood and innervated?
Each division has it’s own large aortic branch to supply blood and it’s own visceral plexus to supply autonomic innervation.
What is the major aortic branch and nerve supply for the foregut?
Celiac trunk; celiac plexus
What structures comprise the foregut?
Stomach, duodenum (first two segments)