umich written quiz – duodenum

7/25/2019 Umich Written Quiz Duodenum

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Umich Written Quiz Duodenum, Pancreas, Liver, and Gallbladder

The structure that traverses the space between the aorta and first part of the

superior mesenteric artery and is vulnerable to the nutcracker-like

compression by these two vessels is the:

Duodenum

Jejunum

Pancreas

Splenic vein

Transverse colon

The correct answer is: Duodenum

The superior mesenteric artery crosses over the third part of the

duodenum, and the aorta is posterior to the third part of the duodenum. If

something causes these vessels to become enlarged, they can crush the

duodenum, and the passage of food will be obstructed. This is often called the

"nutcracker effect," and it is only seen in the third part of the duodenum. Takea look at Netter Plate 292 for an illustration of the third part of the duodenum

lying between these important vessels.

A patient with jaundice was diagnosed with cancer of the head of the

pancreas. Which structure was compressed by the tumor?

Common bile duct

Common hepatic duct

Cystic duct

Left hepatic duct

Right hepatic duct


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The correct answer is: Common bile duct

Tumors in the head of the pancreas often obstruct the common bile duct,

blocking the normal bile recycling circuit. This blockade prevents excretion ofbilirubin, a yellow-colored pigment that is a red blood cell breakdown product.

The accumulation of bilirubin in various tissues, including the skin, causes

jaundice. A tumor in the head of the pancreas would not block the other

ducts--look at Netter 276 to see how all the ducts are related.

A surgeon needs to construct a bypass between the veins of the portal and

caval systems to circumvent insufficient drainage through the naturalportacaval anastomoses. Which plan is likely to be successful?

Coronary vein to right gastroepiploic vein

Inferior mesenteric vein to splenic vein

Left colic vein to middle colic vein

Splenic vein to left renal vein

Superior mesenteric vein to splenic vein

The correct answer is: Splenic vein to left renal vein

The splenic vein is a major vein of the portal system, while the left renal

vein is a major vein of the caval system. These veins are large, so a bypass

between them could be useful for relieving the portal hypertension. The

coronary vein, right gastroepiploic vein, inferior mesenteric vein, splenic vein,

left colic vein, middle colic vein, and superior mesenteric vein are all part of

the portal system. Any bypasses among these veins will not relieve the portal

hypertension.


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A patient was diagnosed with pancreatitis due to a reflux of bile into the

pancreatic duct caused by a gallstone. The stone is likely to be lodged at the:

Common bile duct

Common hepatic duct

Cystic duct

Hepatopancreatic ampulla

The correct answer is: Hepatopancreatic ampulla

The hepatopancreatic ampulla is the very short segment of duct which

represents the joining of the common bile duct and the main pancreatic duct.

Once these two ducts form the hepatopancreatic ampulla in the wall of the

duodenum, the bile and pancreatic enzymes are emptied into the second

portion of the duodenum, through the major duodenal papilla. If a gallstone

was stuck in the hepatopancreatic ampulla, bile could back up and flow

backwards into the main pancreatic duct. If a stone was lodged in the cystic

duct, common hepatic duct, or common bile duct, bile would never even reach

the pancreas. See Netter Plate 276 for an illustration.

An ulcer near the pyloroduodenal junction perforated and eroded a large

artery immediately posterior to the duodenum. The ligation of the eroded

vessel at its origin would LEAST affect the arterial supply to the:

First part of the duodenum

Second part of the duodenum

Greater curvature of the stomach

Head of the pancreas

Tail of the pancreas


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The correct answer is: Tail of the pancreas

The gastroduodenal artery is the artery that has ruptured. This artery

gives off the anterior and posterior superior pancreatoduodenal arteries, whichsupply the first and second parts of the duodenum, as well as the head of the

pancreas. The gastroduodenal artery also gives off the right gastroomental

artery, which supplies the right half of the greater curvature of the stomach. In

contrast, the tail of the pancreas is supplied by the caudal pancreatic artery,

which is a branch of the splenic artery. It would not be affected by damage to

the gastroduodenal artery.

A radiological examination of a patient revealed a large tumor in the quadrate

lobe of the liver. During the surgical removal of the tumor, one of the vessels

that needs to be clamped to effectively control bleeding is the:

Left hepatic artery

Right hepatic artery

The correct answer is: Left hepatic artery

The left and right hepatic arteries help support the parenchyma and

stroma of the liver. The left hepatic artery supplies the left & quadrate lobes of

liver, and part of the caudate lobe. The right hepatic artery supplies the right

lobe and part of the caudate lobe. So, the left hepatic artery must be clamped

to perform surgery on the quadrate lobe.

A 58-year-old patient was diagnosed with a severe case of portal hypertension

due to alcoholic cirrhosis of the liver. It was determined that a bypass between

the vessels of the portal and caval systems was necessary. The plan most

likely to be successful is:

Coronary vein to right gastro-omental vein

Left colic vein to sigmoidal vein


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Inferior mesenteric vein to splenic vein

Splenic vein to left renal vein

Superior rectal vein to inferior rectal vein

The correct answer is: Splenic vein to left renal vein

The splenic vein is a major vein of the portal system, while the left renal

vein is a major vein of the caval system. These veins are large, so a bypass

between them could be useful for relieving the portal hypertension. The

coronary vein, right gastro-omental vein, left colic vein, sigmoidal vein, inferiormesenteric vein, and splenic vein are all part of the portal system. Any

bypasses among these veins will not relieve the portal hypertension. The

superior and inferior rectal veins already form a portal-caval anastomosis;

surgery would not be needed to connect these two venous channels.

However, if too much blood tries to flow through this anastomosis,

hemorrhoids will develop. These veins are not large enough to help relieve

severe portal hypertension.

Upon endoscopic examination of a 65-year-old man who had a history of a

chronic duodenal ulcer, it was found that the ulcer had been eroding the

posterior wall of the first part of the duodenum. If erosion perforates the wall,

the gastric expellant of high acidity would endanger the structures in its

vicinity. Which is least likely to be endangered?

Common bile duct

Gastroduodenal artery

Main pancreatic duct

Portal vein

The correct answer is: Main pancreatic duct


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The pancreas is inferior to the superior portion of the duodenum, and the

main pancreatic duct is found deep within the pancreas. It is not likely that this

structure would be damaged by the duodenal ulcer. The portal vein,

gastroduodenal artery, and the common bile duct all pass immediately deep to

the first part of the duodenum. (The portal vein and common bile duct areassociated with the proper hepatic artery, forming the portal triad.) These

structures would all be at risk from the ulcer. See Netter Plate 279 for a picture

illustrating this relationship.

You are observing a laparoscopic cholecystectomy. The surgeon states that

he is next going to expose the cystic artery in order to staple across it. He

asks you where he should look for it. You reply, "In the triangle of Calot." What

stuctures form this triangle and are the keys to finding the artery?

Common hepatic duct, liver and cystic duct

Cystic duct, right hepatic artery and right hepatic duct

Gall bladder, liver and common bile duct

Left hepatic duct, liver and cystic duct

Right branch of portal vein, liver and common bile duct

The correct answer is: Common hepatic duct, liver and cystic duct

The triangle of Calot is formed by the cystic duct laterally, the liver

superiorly, and the common hepatic duct medially. It is an important landmark

in this region, because the cystic artery can be found in the triangle of Calot.

During a cholecystectomy, the cystic artery needs to be ligated. Although the

cystic artery usually branches from the right hepatic artery, there is some

variation. However, if you locate the triangle of Calot, you can find the cystic

artery in that triangle, trace it back to its origin, and then ligate it there.

A medical student was asked to identify a small specimen taken forpathological examination from a surgically removed duodenum. The student


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noted that the specimen revealed a thin wall and no circular folds. The

specimen is from which segment?

Superior

Descending

Horizontal

Ascending

The correct answer is: Superior

The superior part of the duodenum is the one segment of the duodenum

that has no circular folds. When food enters the duodenum from the pyloric

sphincter, it enters the ampulla, which is a smooth area of the duodenum

containing a high percentage of mucosal cells. These cells secrete mucus to

neutralize the acidic contents of the stomach. If the stomach contents is not

sufficiently neutralized, the thin wall of the ampulla may develop an ulcer. If the

ulcer burns through the entire wall, it might jeopardize the gastroduodenal

artery, lying behind the first segment of the duodenum. The descending,

horizontal, and ascending portions of the duodenum all have circular folds.

For an illustration of the different linings of the duodenum, see Netter Plate

262.

A patient was admitted with symptoms of bowel obstruction. Further

examination revealed that the obstruction was caused by the nutcracker-like

compression of the bowel between the superior mesenteric artery and theaorta. The compressed bowel is most likely the:

Duodenum

Jejunum

Ileum


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Ascending colon

Transverse colon





duodenum, and food will not be able to pass through the duodenum. This is

often called the "nutcracker effect," and it is only seen in the third part of the

duodenum. Take a look at Netter Plate 292 for an illustration of the third partof the duodenum lying between these important vessels.

The division between the true right and left lobes (internal lobes) of the liver

may be visualized on the outside of the liver as a plane passing through the:

gallbladder fossa and round ligament of liver

falciform ligament and ligamentum venosum

gallbladder fossa and inferior vena cava

falciform ligament and right hepatic vein

gallbladder fossa and right triangular ligament

The correct answer is: gallbladder fossa and inferior vena cava

This question is asking you to identify the structures that make the line

that separates the true/functional lobes of the liver. The concept of functional

lobes contrasts with traditional anatomical terminology, which separated the

liver into the left, right, quadrate and caudate lobes. These traditional lobes

were based on anatomical appearance, while the functional lobes are based

on the distribution of the portal vein, hepatic arteries, and hepatic bile ducts.

The functional lobes of the liver are separated into a right and left lobe by the


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gallbladder fossa and the inferior vena cava. So, the old "right lobe"

corresponds to the functional right lobe, while the caudate, quadrate, and left

lobes under anatomical terminology are lumped together as one big left lobe.

During a cholecystectomy (removal of the gall bladder), the surgical

resident accidentally jabbed a sharp instrument into the area

immediately posterior to the epiploic foramen (its posterior boundary).

He was horrified to see the surgical field immediately fill with blood, the

source which he knew was the:

aorta

inferior vena cava

portal vein

right renal artery

superior mesenteric vein

The correct answer is: inferior vena cava

The epiploic foramen, also called the omental foramen, is the

passageway between the greater and lesser peritoneal sacs. The inferior vena

cava lies immediately posterior to this foramen, so this is the vessel that was

probably cut. The aorta lies next the inferior vena cava, but it is a little more to

the left and a little deeper--it does not lie immediately posterior to the epiploic

foramen. The hepatic portal vein is anterior to the epiploic foramen. The right

renal artery is a branch off of the aorta. Like the aorta, it is too deep to be a

vessel immediately behind the foramen. Finally the superior mesentric vein isanterior to the foramen. Remember, this is one of the two vessels that makes

the hepatic portal vein, so if the hepatic portal vein is anterior to the foramen,

the SMV should be too. (See Netter's 256 for some relevant pictures)

RIGHT

A patient was admitted with symptoms of an upper bowel obstruction. Upon

CT examination, it was found that the third (transverse) portion of theduodenum was compressed by a large vessel causing the obstruction. The


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vessel involved is most likely to be the:

inferior mesenteric artery

superior mesenteric artery

inferior mesenteric vein

portal vein

splenic vein

The correct answer is: Superior mesenteric artery




duodenum, and food won't be able to pass through the duodenum. This is

often called the "nutcracker effect," and it is only seen in the third part of the

duodenum. Take a look at Netter Plate 292 for an illustration of the third part

of the duodenum lying between these important vessels. You should know

what structures are involved in the "nutcracker effect" and how they arecausing an upper bowel obstruction!

A 40 year-old male with a long history of duodenal ulcer problems was

brought in for emergency surgery to control severe hemorrhage into the

peritoneal cavity. The surgeons found that erosion by the ulcer of a vessel

passing behind the first part of the duodenum was the source of the

hemorrhage. Which of the following vessels passes behind the first part of theduodenum and would need to be clamped off to control the bleeding?

coronary vein

gastroduodenal artery

inferior pancreatoduodenal arcade


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proper hepatic artery

splenic vein

The correct answer is: gastroduodenal artery

The gastroduodenal artery lies behind the superior part of the

duodenum. It has three branches: the posterior superior pancreaticoduodenal

artery, the anterior superior pancreaticoduodenal artery, and the right

gastroomental artery. The other vessels are not near the superior duodenum.

The coronary vein is made of the right and left gastric veins and located in the

lesser curvature of the stomach. The inferior pancreatoduodenal arcade isfound in the inferior part of the head of the pancreas. It supplies the pancreas

and duodenum. It is near the horizontal (3rd) part of the duodenum, not the

superior part. The proper hepatic artery is a branch of the common hepatic

artery which delivers oxygenated blood to the liver. Finally, the splenic vein

comes from the spleen--it joins the superior mesenteric vein to form the portal

vein.

Which organ becomes retroperitoneal during rotation of the gut tube?

Duodenum

Kidney

Spleen

Stomach

Transverse Colon

duodenum

This question is asking you to identify the organ that is secondarily

retroperitoneal. This means that it started out peritonealized but became

pressed against the posterior body wall and stuck there during development.

Except for the first few centimeters of the superior segment and theduodenojejunal junction, the duodenum is a secondarily retroperitoneal organ


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- it used to have a mesentery, but that was lost during gut rotation. Although

the kidney is a retroperitoneal organ, it is not secondarily retroperitoneal - it

started developing in the retroperitoneum and stayed there. The spleen,

stomach, and transverse colon are all peritonealized. What segments of the

colon are peritonealized? The cecum, transverse colon, and the sigmoid colonare peritoneal, but the ascending and descending colon are retroperitoneal.

To stop hemorrhaging from a ruptured spleen, it was necessary to temporarily

ligate the splenic artery near the celiac trunk. The blood supply to which

structure is least likely to be affected by the ligation?

Duodenum

Greater omentum

Body of pancreas

Tail of pancreas

Stomach


The duodenum receives blood from the gastroduodenal artery, a branch

of the common hepatic artery. It also receives blood from the inferior

pancreatoduodenal artery, which is a branch of the superior mesenteric artery.

So, the duodenum is receiving blood from the common hepatic artery and the

superior mesenteric artery, but it is not receiving any blood from the splenic

artery.

The splenic artery supplies blood to the body of the pancreas with the

dorsal and superior pancreatic arteries; it supplies blood to the tail of the

pancreas with the caudal pancreatic artery. The splenic artery supplies the

fundus of the stomach with short gastric arteries and the left portion of the

greater curvature with the left gastroomental artery. The left gastroomental

artery also supplies blood to the greater omentum through omental branches.

All of these structures would be affected if the splenic artery was ligated.


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A 50-year-old female patient with severe jaundice was diagnosed with

pancreatic cancer. You suspect that the tumor is located in which portion of

the pancreas?

Head

Neck

Body

Tail

Uncinate process

The correct answer is: Head

Tumors in the head of the pancreas often obstruct the common bile duct,

blocking the normal bile recycling circuit. This blockade prevents excretion of

bilirubin, a yellow-colored pigment that is a red blood cell breakdown product.

The accumulation of bilirubin in various tissues, including the skin, causes

jaundice. Tumors in other areas of the pancreas are not as likely to block the

common bile duct and cause jaundice.

A Kocher manuever dissects in the avascular plane behind which organ that

becomes retroperitoneal during rotation of the gut?

Duodenum

Kidney

Spleen

Suprarenal gland

Transverse colon



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A Kocher maneuver involves reflecting the duodenum and pancreas

medially by cutting through the fusion fascia along the right side of the

descending part of the duodenum. This technique is used to gain access

behind the pancreas. However, even if you didn't know the exact definition of a

Kocher maneuver, you could still answer this question. The question is askingyou to pick which organ is secondarily retroperitoneal, and the only

secondarily retroperitoneal organ listed is the duodenum. The kidney and

suprarenal gland were retroperitoneal during the entire developmental

process, and the transverse colon and spleen are peritonealized. So,

duodenum is the only answer that makes sense here.

The inferior mesenteric vein usually joins which vein?

Inferior vena cava

Left renal

Portal

Splenic

Superior mesenteric

The correct answer is: Splenic

The inferior mesenteric vein usually empties into the splenic vein. The

splenic vein and the superior mesenteric vein then unite to form the portal

vein. Look at Netter Plate 290 for a picture of this. Remember--the inferior

vena cava and left renal vein are caval veins--they are not involved in drainingthe gut.

The blockage of a main bile duct in the quadrate lobe will likely cause reduced

flow of bile secretion in the:


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Left hepatic duct

Right hepatic duct

The correct answer is: Left hepatic duct

Like the left hepatic vein, the left hepatic duct drains bile from the left

lobe, quadrate lobe, and part of the caudate lobe of the liver. So, an

obstruction in the quadrate lobe would reduce bile secretion in the left hepatic

duct. The right hepatic duct and hepatic vein drain the right lobe and part of

the caudate lobe.

Regarding the 2nd portion of the duodenum, all are correct EXCEPT:

It is crossed by the transverse colon.

It is thin walled and circular folds are absent in its interior.

It has the opening for the common bile duct and pancreatic duct on its

posteromedial wall.

It is secondarily retroperitoneal.

It is supplied by both the gastroduodenal and superior mesenteric

arteries.

The correct answer is: It is thin walled and circular folds are absent in its

interior

The first part of the duodenum features thin walls and no circular folds. It

is called the ampulla of the duodenum. Once the duodenum turns and

becomes the second part, the walls become thicker, and circular folds

develop. The second part of the duodenum has the hepatopancreatic ampulla

in its medial wall, which is the duct formed as the common bile duct and

pancreatic duct join to empty their secretions into the duodenum. The

transverse colon overlies the second part of the duodenum, and the second

part of the duodenum is a secondarily retroperitoneal organ. Also, rememberthat the anterior and posterior superior pancreaticoduodenal arteries are


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branches of the gastroduodenal artery, which receives blood from the celiac

trunk. The anterior and posterior inferior pancreaticoduodenal arteries receive

blood from the superior mesenteric artery.

A 60-year-old patient who has had a chronic ulcer of the duodenum for many

years was admitted to the hospital with signs of a severe internal hemorrhage.

The ulcer perforated the posterior wall of the first portion of the duodenum and

eroded an artery in that position. The damaged artery was:

Cystic

Gastroduodenal

Hepatic

Left gastric

The correct answer is: Gastroduodenal

The gastroduodenal artery is a branch of the common hepatic artery--it

passes immediately posterior to the first portion of the duodenum, and it can

be damaged if there is an ulcer in this part ot the duodenum. The cystic artery

supplies the gall bladder--it can be located in the triangle of Calot. The proper

hepatic artery is a branch of the common hepatic artery--it travels superior to

the first portion of the duodenum. The left gastric artery is a branch of theceliac trunk--it supplies the left side of the lesser curvature of the stomach.

umich written quiz – duodenum

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