Abdominal Viscera

Question 1

At what vertebral level does the esophagus pierce the diaphragm to enter the abdomen?

Answer 1

T9/T10

Question 2

What happens to the vagal trunks associated with the esophagus in the thorax?

Answer 2

The left and right vagi become anterior/posterior respectively and pass through the diaphragm to supply parasympathetic innervation to the prevertebral plexuses of the abdomen.

Question 3

Is there an anatomical sphincter at the gastroesophageal junction?

Answer 3

NOOOO

Question 4

What keeps gastric reflux from normally occurring at the gastroesophageal junction?

Answer 4

It is a physiological sphincter, the negative pressure of the thorax keeps the esophagus pressed closed.

Question 5

List organs that have an anatomical relationship with a specific aspect of the stomach.

Answer 5

Anterior/superior: anterior abdominal wall, left costal margin, diaphragm; Left: spleen; Right: quadrate and left lobes of the liver; Posterior: diaphragm, left suprarenal gland, upper pole of left kidney, pancreas and left colic flexure.

Question 6

What divides the right and left lobes of the liver anatomically when viewed from its
anterior aspect?

Answer 6

The falciform ligament

Question 7

What does the anatomical arrangement between the visceral peritoneum of the liver and the diaphragm form by its reflection.

Answer 7

It creates the bare area of the liver, left triangular ligament and right coronary ligaments.

Question 8

What does the bare area of the liver come into contact with? Be specific.

Answer 8

The bare underside of the diaphragm.

Question 9

Why is the bare area of the liver important?

Answer 9

Liver abcesses can pass “silently” up through the diaphragm giving little notice before perforating through into the pleural cavity.

Question 10

What is the function of the gallbladder?

Answer 10

To store and concentrate bile secreted by the liver.

Question 11

Why does the gallbladder have a serosa and an adventitia?

Answer 11

That portion of the gallbladder exposed to the abdominal cavity is covered with peritoneum, that portion attached to the underside of the liver has no peritoneum = adventitia.

Question 12

List the 3 parts of the small intestinal, in order, from proximal to distal.

Answer 12

Duodenum, jejunum, ileum.

Question 13

Which of these 3 regions is predominantly retroperitoneal?

Answer 13

The duodenum.

Question 14

Which of these 3 regions are mesenterized?

Answer 14

Jejunum and ileum

Question 15

In which direction does the root of the mesentery cross the posterior abdominal wall?

Answer 15

From upper left to lower right.

Question 16

How can you differentiate the ileum from the jejunum?

Answer 16

The fat within the mesentery does not encroach upon the wall of the jejunum leaving “mesenteric windows” (except in obese individuals); in the ileum the fat comes right up to the ileal wall obliterating these windows.

Question 17

What is a taeniae coli?

Answer 17

One of 3 longitudinal bands of smooth muscle.

Question 18

What is the function of these 3 taeniae?

Answer 18

They “shorten” the tube, gathering it up and creating pocket-like compartments called haustra.

Question 19

What is the function of a haustral compartment?

Answer 19

They slow down the movement of feces through the large intestine allowing water resorption to occur.

Question 20

Where do the taenia coalesce into a complete outer layer of longitudinal smooth
muscle?

Answer 20

On the surface of the rectum as well as over the surface of the appendix.

Question 21

Identify the abdominal organs considered to be retroperitoneal.

Answer 21

Descending aorta, duodenum, pancreas, inferior vena cava, suprarenal glands, kidneys, ureters, ascending and descending colon.

Question 22

List the 4 parts of the duodenum.

Answer 22

1st (superior); 2nd (descending); 3rd (horizontal); and 4th (ascending).

Question 23

Which portion contains the duodenal papilla?

Answer 23

The 2nd (descending).

Question 24

What empties into the duodenal lumen at this papilla?

Answer 24

Bile and pancreatic enzymes.

Question 25

What organ is found nestled within the C-shape concavity of the duodenum?

Answer 25

The head of the pancreas

Question 26

What two important anatomical structures lie posterior to the 1st part of the duodenum?

Answer 26

Biliary duct (common bile duct) and main pancreatic duct.

Question 27

Which anatomical structures pass anterior to the 3rd part of the duodenum?

Answer 27

The supermester mesenertic vein and artery.

Question 28

Cite the anatomical relationship each of the following has with the pancreas:
duodenum, spleen, formation of the hepatic portal vein, superior mesenteric a. and
v., the splenic a., and the hilus of the spleen.

Answer 28

Duodenum: head of pancreas nestled in C-shaped concavity; hepatic portal vein: formed behind the neck; Superior mesenteric a. and v.: pass anterior to the uncinate process; splenic a.: often lies embedded along the superior border of the pancreas; spleen: the tail of the pancreas lies in the hilus of the spleen.

Question 29

List the 3 main arterial trunks off the aorta that are responsible for supplying the G.I.T.

Answer 29

Celiac trunk; superior mesenteric and inferior mesenteric aa.

Question 30

Which general region of the gut does each of these 3 main arteries of the aorta supply?

Answer 30

Celiac trunk: foregut; superior mesenteric a.: midgut; and inferior mesenteric a.: Hindgut.

Question 31

What specific portions of the tubular G.I.T. are contained within each of these regions?

Answer 31

Foregut: lower esophagus to mid duodenum; midgut: mid duodenum to mid transverse colon; hindgut: mid transverse colon to rectum.

Question 32

Know the anatomical extent of each of viscera supplied by each of these 3 aa.

Answer 32

Celiac trunk: lower esophagus to mid duodenum; superior mesenteric a.: mid duodenum to mid transverse colon; inferior mesenteric a.: mid transverse colon to rectum.

Question 33

Where does the formation of the hepatic portal vein occur?

Answer 33

Posterior to the head/neck of the pancreas.

Question 34

What is the function of the hepatic portal system?

Answer 34

To ensure that ingested materials from the G.I.T. are screened by the liver prior to release into the systemic circulation.

Question 35

What is the importance of the portocaval anastomoses?

Answer 35

They are indicative of a blockage of either of the two circulatory systems (hepatic portal and systemic) concerned.

Question 36

Name the location of at least 3 of the more clinically relevant ones.

Answer 36

Esophagus: esophageal varices, anal canal: hemorrhoids, and umbilicus: caput medusa.