1. Label the diagram
B
A
D
G
C
E
F
A- Pylorus
B- Duodenum
C- Transverse Colun
D- Jejunum
E- Ileum
F- Sigmoid colon
G- Appendix
2. What is the peritoneum, what are its layers?
Peritoneum is a large, thin transparent sheet of serous membrane which lines the walls of the abdominopelvic
cavity and is reflected onto the viscera. Layers:
a. Parietal peritoneum- lines the abdominal and pelvic walls
b. Visceral peritoneum- covers the abdominal and pelvic organs
c. Peritoneal cavity- potential space between adjacent layers of peritoneum usually containing a small amount
of fluid.
3. What organs are in the peritoneal cavity?
There are no organs in the peritoneal cavity, the cavity is a potential space between the viscera (on the organs)
and the parietal peritoneum.
4. What is the mesentery?
It is 2 layers of peritoneum that surrounds the blood vessels that supply organs in the abdomen. It is continuous
with the visceral peritoneum and is composed of vessels and fatty connective tissue. It holds an organ to the
abdominal wall and allows it to move freely within certain limits.
5. How is the peritoneal cavity subdivided? How are they connected? How does this affect abdominal immunity?
Divided into 2 sacs, greater and lesser:
a. Greater sac- most of the abdomen is covered by this sac. It is split into 2 compartments, supracolic and
infracolic, division occurs because of the mesentery of the transverse colon. The mesentery of the small
intestine will split the infracolic compartment into right and left. Most of the abdominal wall is covered by
this sac
b. Lesser sacn (omental bursa)- This sac is located posterior to the stomach, liver, lesser omentum and other
associated structures. The lesser sac is limited by a superior and inferior recess. The superior recess is
limited by the diaphragm, posterior layer of the coronary ligament of the liver. The inferior recess is
between parts of the layers of the greater omentum. The lesser sac permits movement of the stomach.
The greater and lesser sac communicate with each other through the omental foramen. Note that the omental
foramen is located “within” the lesser omentum. The omental foramen is bounded by: anteriorhepatoduodenal ligament (free end of lesser omentum) that contains the hepatic vessels; posterior- the IVC and
muscular band, right crus of the diaphragm; superiorly- the liver; inferiorly- first part of the duodenum.
Immunity-The cavities are closed in males, but in females there is an opening through the reproductive system.
This gives females higher immunity because it allows for shared immune signals between the abdomen and the
rest of the body. If a male gets an infection in the abdomen, he does not have the antibodies from the rest of
the body to fight it.
6. What are intraperitoneal organs?
These are organs that are covered with visceral peritoneum, except at the sites where the mesentery attaches.
These organs have mesentery and are almost completely surrounded by visceral peritoneum
7. What are retroperitoneal organs?
These are organs that are attached directly to the back wall of the abdomen, they do not have mesenteries and
are not covered by visceral peritoneum on one or more sides.
8. What are secondarily retroperitoneal organs?
These are organs that once had a mesentery but were moved to the abdominal wall and therefore do not have
mesenteries anymore, the blood vessels that would have made up the mesenteries are still present, however.
9. Identify each organ as retroperitoneal
Esophagus
Stomach
Liver
Pancreas
RETROperitoneal
INTRAperitoneal (greater and lesser omentum)
INTRAperitoneal
SECONDARILY RETROperitoneal except for tail that may extend into the
lienorenal ligament
Duodenum
SECONDARILY RETROperitoneal except for a portion of the first segment that is
attached to the hepatoduodenal ligament
Jejunum & Ilium INTRAperitoneal (the mesentery)
Cecum
INTRAperitoneal (mesocecum)
Appendix
INTRAperitoneal (mesoappendix)
Ascending Colon
Transverse Colon
Descending Colon
Sigmoid Colon
Rectum
Kidneys
Suprarenal Glands
Spleen
SECONDARILY RETROperitoneal
INTRAperitoneal (transverse mesocolon)
SECONDARILY RETROperitoneal
INTRAperitoneal (sigmoid mesocolon)
RETROperitoneal
RETROperitoneal
RETROperitoneal
INTRAperitoneal (splenorenal and gastrosplenic ligaments)
10. What is an omentum? How many are there?
An omentum is a double layer of peritoneum attached to the stomach and proximal part of the duodenum,
there are 2 types, greater omentum and lesser omentum.
a. Greater omentum- Attaches to the stomach along the greater curvature and extends to the posterior
abdominal wall. The greater omentum is divided into 3 ligaments, (gastrophrenic, gastrosplenic and
gastrocolic). This omentum, the gastrocolic ligament in particular, covers part of the abdomen. The
gastrocolic ligament is in between the stomach and the transverse colon, the gastrophrenic ligament is in
between the stomach and the inferior surface of the diaphragm and the gastrosplenic ligament is between
the stomach and the spleen. All of these ligaments have a constant attachment to the greater curvature of
the stomach.
b. Lesser omentum- A smaller omentum that extends from the lesser curvature of the stomach and the
proximal duodenum to the liver. It also connects the stomach to the triad of vessels that enter the liver
(hepatic portal vein, hepatic artery and bile duct). It is composed of 2 different ligaments, the
hepatoduodenal ligament and the hepatogastric ligament. Hepatogastric- membranous portion of lesser
omentum, connects liver and stomach. Hepatoduodenal- thickened free edge of lesser omentum, connects
liver to duodenum.
11. What is a peritoneal ligament? What are examples?
A peritoneal ligament is a double layer of peritoneum that connects different organs to each other or organs to
the body wall. Most of the examples are listed in the previous answer, except for the falciform ligament which
connects the liver to the abdominal body wall.
12. Label the following diagrams. What is A/B and C/D/E
C
A
D
B
E
ABCDE-
hepatogastric ligament
Hepatoduodenal ligament
Gastrophrenic ligament
Gastrosplenic ligament
Gastrocolic ligament
A
B
C
D
E
F
J
I
G
H
ABCDEFGHIJ-
Superior recess of lesser sac
Lesser omentum
Lesser sac (omental bursa)
Omental foramen
Inferior recess of omental bursa
Transverse mesocolon
Greater omentum
Greater sac
Transverse colon
Greater sac
B
D
A
C
E
A- Lesser Sac
B- stomach
C- Hepatorenal pouch
D- Gastrosplenic ligament
E- Splenorenal ligament
13. What are peritoneal folds? Name and identify them in the figure below.
A reflection of peritoneam that is raised from the body wall by underlying blood vessels, ducts, and ligaments
formed by obliterated fetal vessels. Some peritoneal folds contain actual blood vessels.
A
B
C
A- Lateral umbilical fold- contains the inferior epigastric vessels
B- Medial umbilical fold- contains obliterated umbilical artery
C- Median umbilical fold- contains urachus
14. What is the peritoneal recess?
A pouch of peritoneum formed by peritoneal folds or ligaments. Examples are the inferior recess of the omental
bursa or the hepatorenal pouch
15. What are peritoneal gutters? Describe each one.
They are communications between the supracolic and infracolic segments where fluids can flow through. Allows
for conduction of different materials. Examples are in the diagram below.
D
A
E
F
B
G
H
C
I
ABCDEF-
Supracolic compartment- Above the transverse colon
Right paracolic gutter- Contains less fluid because of phrenicocolic ligament
Infracolic compartment- Below the transverse colon
Transverse colon- separates major components of great sac
Left paracolic gutter- less fluid because of phrenicocolic ligament
Right infracolic gutter- fluid sits here until there is overflow then goes to LIG and subsequently into the
retrouterine pouch
G- Mesentary of small intestine
H- Left infracolic gutter- fluid goes straight into the retrouterine pouch
I- REtrouterine pouch
16. What is the role of the phrenicocolic ligament?
The role of the phrenicocolic ligament is to anchor the colon to the back wall and ensure that fluid does not
travel directly into the lower pouch from the supracolic compartment but instead goes through the right
paracolic gutter.
17. What are the 3 main arteries that come off the abdominal aorta? What organs do they individually supply?
a. Celiac artery- Located in between the liver and the stomach, comes off the abdominal aorta immediately
after it crosses the diaphragm, it supplies the liver, stomach and spleen.
b. Superior mesenteric- supplies the small intestine, large intestine and upper mesentery, also the ascending
and transverse colons
c. Inferior mesenteric- Descending colon and rectum.
18. Describe the branches off the celiac artery. Describe which organs they supply.
Artery
Organs supplied
Left Gastric
Lesser curvature of the stomach on the left
Splenic
Superior Spleen; runs behind the spleen
Pancreatic
Pancreas
Posterior Gastric
Poserior side of stomach, present in only 60% of ppl
Short gastric
Stomach
Left gastro-omental
Greater curve of stomach
Common hepatic
Proper hepatic
Liver
Right gastric
Lesser curvature of the stomach, on the right
Left hepatic
Left lobe of the liver
Right hepatic
Right Lobe of liver
Cystic
Gall Bladder
Gastroduodenal
Duodenum, greater curvature of the stomach on right
supraduodenal
Superior pancreaticoduodenal
Right gastro-omental
19.
C
B
A
Greater curvature of the stomach, right
O
N
M
D
L
E
F
G
H
K
I
J
ABCDEFGH-
Celiac Trunk
Common hepatic
Left and right hepatic
Cystic artery
Proper hepatic
Right gastric
Gastroduodenal
Supraduodenal
IJKLMNO-
Superior pancreaticoduodenal
Right gastro-omental
Left gastro-omental
Short gastric
Posterior gastric
Splenic
Left gastric
20. Name the branches off the superior mesenteric and what they supply.
a. Inferior pancreaticoduodenal- pancreas/duodenum
b. Intestinal branches- random points along the intestine
c. Ileocolic- Ileum and part of colon
d. Right colic- middle of ascending colon
e. Middle Colic- middle of transverse colon
21. What is the marginal artery of Drummond? Why is it needed?
It is an anastamosing channels connecting branches of the superior mesenteric and inferior mesenteric arteries
(eg. The right/ middle and left colics are all “connected” through this system). It is needed to prevent necrosis at
different parts of the colon.
22. Name and identify.
A
E
D
B
C
A- Middle colic artery
B- Right colic artery
C- Ileocolic
D- Superior mesenteric
E- Inferior pancreaticoduodenal
23. What are the branches off the inferior mesenteric and what do they supply?
a. Left colic-Descending colon
b. Sigmoidal- Series of arteries supplying the sigmoidal colon
c. Superior rectal-rectum
24. Name and label
A
B
C
D
A- Left colic artery
B- Inferior mesenteric artery
C- Superior rectal artery
D- Sigmoidal arteries
25. What is the hepatic portal vein system?
It is the system that carries blood from the GI tract back to the heart. It has a portal vein system because it
carries blood from 2 capillary beds. One bed is near the GI organs, the other is in the liver. There is a portal vein
that carries blood from the GI organs to the liver. The portal vein is formed from the splenic vein and the
superior mesenteric vein. The inferior mesenteric vein drains into the splenic vein. Some of the gastric veins
drain directly into the portal vein.
Name and identify.
A
E
D
B
C
A- Portal Vein
B- Superior Mesenteric Vein
C- Inferior mesenteric Vein
D- Splenic Vein
E- Gastric vein
26. What is portal hypertension? What is its effect and where can that effect be seen?
Portal hypertension occurs when there is a blockage in the portal vein. Because of this flow of blood into the
liver (and subsequently to the heart) is blocked. Therefore blood needs another path to take to the heart. It will
use other systems to get to the heart and form large varicose veins in different parts of the body. There are 4
key spots:
a. Esophageal varices- Occurs near esophagus, blood tries to go to azygous
b. Anorectal varicies- Occurs near rectum, blood trying to get to iliac
c. Caput medusae- Occurs at umbilicus, trying to get to epigastric
d. Retroperitoneal- Goes to Renal to IVC instead of colic, duodenal and pancreatic.
Treatment is a liquid diet, put in shunts or a liver transplant.