DISSECTION 27
Duodenum, Hepatoduodenal Ligament,
Liver and Pancreas
References: M1 239-241, 265-290; N270-271, 279-280, 288-294; N278-279, 287-288, 298-304;
R 286-289, 299-306
AT THE END OF THIS LABORATORY PERIOD YOU WILL BE RESPONSIBLE FOR THE
IDENTIFICATION AND DEMONSTRATION OF THE STRUCTURES LISTED BELOW:
1. Viscera, visceral parts and features: duodenum (superior portion, descending portion, horizontal
portion, ascending portion), common bile duct, cystic duct (spiral fold), right hepatic duct, left
hepatic duct, common hepatic duct, major duodenal papilla, pancreas (head, uncinate process,
pancreatic incisure, body, tail), main pancreatic duct, accessory pancreatic duct, hepatopancreatic
ampulla, liver (right lobe, left lobe, quadrate lobe, caudate lobe, bare area, porta hepatis),
gallbladder.
2. Ligaments and mesenteries: hepatoduodenal, coronary, falciform, lienorenal, ligamentum
teres hepatis, ligamentum venosum.
3. Vessels: hepatic artery, left and right hepatic branches, cystic artery, gastroduodenal artery,
inferior pancreaticoduodenal arteries, superior pancreaticoduodenal arteries, portal vein, superior
mesenteric, inferior mesenteric vein, inferior vena cava, hepatic veins, splenic vein.
YOU SHOULD ALSO BE ABLE TO DO THE FOLLOWING THINGS:
1. Give the major relationships of the duodenum and the pancreas.
2. Name the four parts of the duodenum and describe the relationship of each part to the mesenteries
and vessels which cross it. Be able to explain these relationships in terms of the development of
the duodenum.
3. Describe the relationship of the parts of the pancreas to the superior mesenteric vessels and explain
the development of the pancreas and its duct system.
4. Describe the relationship of the portal vein, common bile duct, and hepatic artery to each other in
the hepatoduodenal ligament.
5. Describe the route taken by bile from the liver to the duodenum.
6. List the functions of the gallbladder. Give the relations of the gallbladder.
7. Demonstrate understanding of the blood flow through the liver. Be able to trace the route of blood
flow from the gastrointestinal tract to the liver and from the liver to the heart.
8. Describe the route of blood flow through the fetal liver. Name the adult remnants of the vessels
that carry blood from the placenta to the heart.
9. Name the vessels from which aberrant hepatic arteries most commonly arise.
10 Describe the surface projection of the liver on the anterior wall.
Dissection 27, Duodenum, Liver, Pancreas
Page 2
Duodenum
Differentiate the four parts of the DUODENUM
and study the relationships of each part (G2.33,
37; N270, 271; N278, 279). Note the relationship
of the SUPERIOR PORTION OF THE DUODENUM to
the gallbladder; the relationship of the
DESCENDING PORTION
to the transverse
mesocolon, to the right kidney, and to the head of
the pancreas; the relationship of the HORIZONTAL
PORTION to the mesentery of the jejunum,
superior mesenteric vessels, to the inferior vena
cava, and to the aorta. In your cadaver, see if
there is a clear distinction between the horizontal
portion and the ASCENDING PORTION of the
duodenum.
Make an incision through the anterior wall of
the right portion of the stomach and continue it
through the pyloric sphincter into the superior
portion of the duodenum. Compare the muscular
wall in this region of the stomach and in the
duodenum. Observe the thick muscular wall in
the stomach, and the mucosal folds (or rugae)
which line the interior of the stomach (G2.27;
N267; N275).
Hepatoduodenal Ligament
To observe the COMMON BILE DUCT, the
HEPATIC ARTERY, and the PORTAL VEIN in the
HEPATODUODENAL LIGAMENT, the peritoneum
enclosing these three structures should be
dissected away (G2.55A; N265, 280; N273, 288).
Note the relationship of these three structures.
Make a vertical incision, through peritoneum
only, lateral to the descending portion of the
duodenum. Reflect the descending duodenum
and the head of the pancreas to the left until you
are able to see the common bile duct entering the
head of the pancreas. Clean the common bile
duct toward the liver and identify the CYSTIC
DUCT and the COMMON HEPATIC DUCT, which
unite to form the common bile duct (G2.54B;
N285; N294). Identify the RIGHT and LEFT
hepatic ducts which unite to form the COMMON
HEPATIC DUCT. Follow the cystic duct to the
GALLBLADDER. Open the gallbladder and extend
the incision into the cystic duct and examine the
SPIRAL FOLD in the cystic duct (G2.37B; N285;
N294). Follow the hepatic artery to the liver and
identify its RIGHT and LEFT HEPATIC
BRANCHES. Look for the CYSTIC ARTERY, which
is usually a branch of the right hepatic artery.
Make an incision in the anterior wall of the
descending duodenum and identify the MAJOR
DUODENAL PAPILLA (G2.37B; N271, 287; N279,
295). It may be partially hidden by a hood-like
fold of mucous membrane. Feel for the mural
portion of the common bile duct in the duodenal
wall above the major papilla. Using a needle and
syringe, inject a small amount of colored fluid
into the supraduodenal portion of the common
bile duct while observing the major duodenal
papilla (or the mucous membrane of the
posteromedial duodenal wall if you have not yet
located the papilla). In some cadavers, a minor
duodenal papilla may be found.
Pancreas
The PANCREAS lies in a horizontal position in
front of the inferior vena cava and the aorta. The
HEAD of the pancreas fits into the curve of the
duodenum (N288; N298). Clean the SUPERIOR
MESENTERIC VESSELS where they pass anterior
to the horizontal portion of the duodenum. Note
on which side of the artery the vein lies. Identify
the UNCINATE PROCESS of the pancreas which
lies posterior to the superior mesenteric vessels.
Consult your text for the embryonic origin of the
uncinate process.
The uncinate process is
separated from the rest of the pancreas by the
PANCREATIC INCISURE (or notch) through which
the superior mesenteric vessels pass. The BODY
of the pancreas lies to the left of the pancreatic
incisure. The TAIL of the pancreas lies in the
LIENORENAL LIGAMENT with the splenic vessels.
Clean the SPLENIC VEIN and identify the
termination of the INFERIOR MESENTERIC VEIN.
See if the inferior mesenteric vein drains into the
splenic vein, the superior mesenteric vein or
directly into the portal vein in your cadaver.
Clean the portal vein from its origin to the
entrance of its right and left branches into the
substance of the liver in the PORTA HEPATIS.
Identify INFERIOR PANCREATICODUODENAL
ARTERIES branching from the superior mesenteric
Dissection 27, Duodenum, Liver, Pancreas
and
SUPERIOR
PANCREATICODUODENAL
ARTERIES from the GASTRODUODENAL (G2.34;
N291-294; N301-304).
Remove glandular tissue from the body of the
pancreas until you can identify the MAIN
PANCREATIC DUCT. Follow this duct toward the
duodenum, and if possible, identify the
ACCESSORY PANCREATIC DUCT. Demonstrate
the union of the main pancreatic duct and
common
bile
duct
to
form
the
HEPATOPANCREATIC AMPULLA (ampulla of
Vater) (G2.37B, 37C, 38; N287, 288; N295, 298)
Liver
The remaining dissection is to be done only at
the odd numbered tables at this time. The liver
should be left in the cadavers at the even
numbered tables.
Identify the CORONARY LIGAMENT and the
FALCIFORM LIGAMENT (G2.19, 49; N267, 279;
Page 3
to the body wall as possible, and if necessary, strip
peritoneum away from the diaphragm rather than
allowing it to tear from the liver. The object is to
remove the liver with as many of its peritoneal
coverings and ligaments as possible. Cut through
the hepatogastric ligament near its attachment to
the stomach. Then identify the INFERIOR VENA
CAVA and cut it just above the right renal vein.
Cut through the root structures of the liver (portal
vein, hepatic artery, common bile duct) about half
way between the duodenum and the liver. Cut
across the remaining attachments of the liver to
the diaphragm.
Make a careful study of the liver identifying
its peritoneal attachments, its BARE AREA,
CAUDATE, QUADRATE, RIGHT, and LEFT LOBES,
BILE DUCTS, ARTERIES, and VEINS, including the
HEPATIC VEINS.
Identify the LIGAMENTUM
VENOSUM, and the LIGAMENTUM TERES
HEPATIS (G2.49, 50; N279; N287).
N275, 287). Cut them as close to their attachment
______________________________________________________________________________________
STUDY QUESTIONS
1.
Trace bile from the right lobe of
the liver to the gallbladder and then
from the gallbladder to the duodenum
naming all ducts traversed.
1.
Right hepatic duct -- common hepatic duct -- cystic
duct -- gallbladder -- cystic duct -- common bile
duct -- hepatopancreatic ampulla -- duodenum.
2.
What are the functions of the
gallbladder?
2.
Storage and concentration of bile.
3.
What is the spiral fold?
3.
The spiral fold is a mucosal fold located in the
cystic duct.
What is its function?
4.
What are the names of the parts
of the duodenum?
It keeps the cystic duct constantly open so that bile
can flow unimpeded in either direction.
4.
First part -- superior part; second part --descending
part; third part – horizontal part; fourth part -ascending part.
Dissection 27, Duodenum, Liver, Pancreas
Page 4
5.
What is the principal posterior
relation of the second part of
the duodenum?
5.
The hilum of the right kidney.
6.
What structure crosses the middle
of the second part of the duodenum
anteriorly?
6.
The transverse mesocolon.
7.
What two important structures lie
directly medial to (to the left of) the
second part of the duodenum?
7.
The head of the pancreas and the common bile
duct.
8.
What are the relations of the third
part of the duodenum?
8
Cranially, the head and uncinate process of the
pancreas. Ventrally, the superior mesenteric
vessels in the mesentery of the jejunum and ileum.
Dorsally, the aorta and inferior vena cava, the right
ureter, and the inferior mesenteric artery.
9.
When an accessory pancreatic duct
is present, where does it end?
9.
It ends in the minor duodenal papilla.
How is it related to the common
bile duct?
It passes ventral to the common bile duct.
10. What is the duodenal cap or
duodenal bulb?
10. The superior part of the duodenum.
11. Where is the spleen located?
11. High up in the left upper quadrant well under the
costal margin.
What would you ask a patient to
do in order to give you a better
chance of palpating an enlarged spleen?
Ask him to take a deep breath.
Is a normal spleen palpable?
A normal spleen is not palpable.
12. What border of the liver does
the physician attempt to palpate
on physical examination?
12. The inferior margin.
13. Does the liver move with respiration?
13. Yes.
14. How far superiorly with respect to
the anterior thoracic wall does the
diaphragmatic surface of the liver
extend?
14. To about the level of the fifth rib on the right side
and the fifth intercostal space on the left side.
Dissection 27, Duodenum, Liver, Pancreas
Page 5
15. What is the porta hepatis?
15. A transverse fissure on the visceral surface of the
liver between the quadrate and caudate lobes.
16. What structures enter and leave the
liver at the porta hepatis?
16. The right and left hepatic arteries, the right and left
branches of the portal vein, the right and left
hepatic ducts.
17. How does blood get out of the liver?
17. Through the hepatic veins which drain into the
inferior vena cava.
18. In the fetus, what is the exact route
of blood flow from the left umbilical
vein to the inferior vena cava?
18. Left umbilical vein -- ductus venosus -- inferior
vena cava.
19. What ligaments remain in the adult
as derivatives of these vessels?
19. Ligamentum teres hepatis and the ligamentum
venosum.
20. What is the most common source
of an aberrant left hepatic artery?
20. The left gastric artery.
Of an aberrant right hepatic artery?
21. The portal vein is formed by the
union of which vessels?
The superior mesenteric artery.
21. The superior mesenteric vein and the splenic vein.
Where does this union occur?
Dorsal to the pancreas.
22. Where does the portal vein lie with
respect to the other structures in the
hepatoduodenal ligament?
22. The portal vein lies dorsal to the hepatic artery and
to the left of the common bile duct.
23. Label as indicated:
23.
a. inferior vena cava
b. right lobe of liver
c. gallbladder
d. quadrate lobe
e. fissure for the ligamentum teres
f. left lobe
g. porta hepatis
h. fissure for the ligamentum venosum
i. caudate lobe
Dissection 27, Duodenum, Liver, Pancreas
24. Label as indicated:
Page 6
24. a. hepatopancreatic ampulla
b. common bile duct
c. cystic duct
d. gallbladder
e. right hepatic artery
f. left hepatic duct
g. left hepatic artery
h. left branch of portal vein
i. common hepatic duct
j. left gastric artery
k. splenic artery
l. gastroduodenal artery
m. splenic vein
n inferior mesenteric vein
o. superior mesenteric vein
25. In what part of the duodenum are peptic ulcers usually located? Perforation of the duodenal wall by such an
ulcer would allow leakage of duodenal contents into what space, if the ulcer were on the anterior wall?
Posterior wall?
26. What are accessory hepatic ducts? What is their significance?
27. List four sites where portal systemic anastomoses occur in patients with portal hypertension. Which of these
is the most important clinically?
LJ:bh
revised
06/8/09