GI Viscera II

Question 1

Trace the structures of the extrahepatic biliary tree

Answer 1

Right and Left Hepatic ducts merge to become Common Hepatic Duct, Cystic Duct merges with this to form Common Bile Duct

Question 2

What is the narrowest part of the extrahepatic biliary tree and what is the clinical significance of this?

Answer 2

Where the common bile duct and pancreatic duct merge into the duodenum. Gallstones can get lodged here (as well as other places in the tree)

Question 3

Inflammation of the gallbladder might trigger inflammation in and eventually fistulas with what two neighboring structures?

Answer 3

Duodenum and Transverse Colon

Question 4

What structures does the extrahepatic biliary tree connect to upstream, what structure downstream, and what also flows into this downstream structure at a nearby site?

Answer 4

Liver and gallbladder (upstream) to duodenum (downstream). The pancreas also connects into the duodenum at this site via the main pancreatic duct

Question 5

Gallstones stuck at the common bile duct-duodenum junction may cause bile to back up into what structure and what structure may act as a relief valve in some individuals?

Answer 5

May backup into the pancreas. Individuals with an accessory pancreatic duct may use this as a relief valve

Question 6

For gallstones lodged in the cystic duct and common bile duct respectively, will the patient present with jaundice or not, and why?

Answer 6

Cystic duct - No, only the gallbladder is occluded (not liver), Common bile duct - Yes, both gallbladder and liver are occluded

Question 7

Three common areas of referred pain from biliary disease

Answer 7

Right upper quadrant, right back at level of RUQ, right shoulder (especially into back right shoulder)

Question 8

Where is the common bile duct inserted into the duodenum?

Answer 8

In the second part of the duodenum

Question 9

What type of papilla are present in the section of the duodenum receiving the common bile duct and major pancreatic duct, and what section of the duodenum is this?

Answer 9

Second section of duodenum, major papilla are present

Question 10

In what percentage of the population is an accessory pancreatic duct present, and in these individuals does this duct attach proximal or distal to where the major pancreatic duct attaches to the duodenum?

Answer 10

10 percent of individuals. The accessory pancreatic duct attaches proximal to where the major pancreatic duct attaches

Question 11

In individuals with an accessory pancreatic duct, what type of duodenal papilla is present at the location that this duct attaches?

Answer 11

Minor duodenal papilla (in contrast to major papilla present where major pancreatic duct attaches)

Question 12

What is the triangular ligament of the liver?

Answer 12

The space between the anterior and posterior leaves of the coronary ligaments

Question 13

Where is the gallbladder relative to the liver?

Answer 13

Along the posteroinferior surface

Question 14

Where is the round ligament of the liver found?

Answer 14

In the free margin of the falciform ligament

Question 15

What separates the left and right anatomical lobes of the liver and what is this structure composed of?

Answer 15

The falciform ligament, which is really peritoneum

Question 16

What anatomical lobe of the liver are the quadrate and caudate lobes a part of, and where are these two lobes in relation to each other?

Answer 16

They are part of the anatomical right lobe and the quadrate is inferior to the caudate

Question 17

How many functional segments are there to the liver and how many are surgically resectable?

Answer 17

8. They are all surgically resectable.

Question 18

What are the functional segments of the liver based upon?

Answer 18

Distribution of the portal triad

Question 19

What portion of blood flow into the liver comes from the portal vein?

Answer 19

75-80 percent

Question 20

What are three things the inferior mesenteric vein may do at its termination and which is most common?

Answer 20

Terminate into the splenic vein (most common), Terminate into the superior mesenteric vein, or terminate directly into the portal vein

Question 21

Three most common places of extrahepatic portocaval anastamosis

Answer 21

1) Deep to the umbilicus, 2) At the gastroesophageal junction, 3) In the distal sigmoid colon

Question 22

What is distinguishing about the superior border of the spleen?

Answer 22

It is notched (remnant of the lobular nature of the spleen during development)

Question 23

Where is the largest aggregation of lymphatic tissue in the human body?

Answer 23

The spleen

Question 24

Give the two names for the area between the ascending and transverse colon

Answer 24

Hepatic flexure, Right colic flexure

Question 25

Give the two names for the area between the transverse and descending colon

Answer 25

Splenic flexure, left colic flexure

Question 26

What are the jejunum and ileum attached to?

Answer 26

The root of the mesentery

Question 27

List the structures crossed by the root of the mesentery

Answer 27

3rd and 4th portions of duodenum, Abdominal aorta, IVC, Right ureter, Right psoas muscle, Right gonadal vessels

Question 28

Give the preganglionic and postganglionic courses of sympathetic innervation to the jejunum and ileum

Answer 28

Preganglionic - Greater and less thoracic splanchnic nerves (T5-T9) synapsing in celiac and superior mesenteric ganglia. Postganglionic - Fibers follow blood vessels to the target organs

Question 29

What is the source of parasympathetic innervation to the ileum and jejunum?

Answer 29

Preganglionic fibers traversing the vagal trunks (postganglionic cells located on or near target organs)

Question 30

Name the parts of the colon which are retroperitoneal

Answer 30

Ascending and descending colon

Question 31

Name the parts of the colon which are peritoneal

Answer 31

Cecum, Transverse Colon, Sigmoid Colon

Question 32

What are the tenia coli?

Answer 32

3 narrow, longitudinal bands of smooth muscle on the cecum through sigmoid colon which turn into a longitudinal coat approaching the rectum

Question 33

What are the haustra?

Answer 33

Small pouches caused by sacculation which give the colon a segmented appearance

Question 34

What is the most common location of the appendix and in what percentage of individuals is this the case?

Answer 34

Retrocecal (65 percent of individuals)

Question 35

What organs does the SMA supply?

Answer 35

Portions of duodenum and pancreas, Jejunum, Ileum, Appendix, Cecum, Ascending Colon, 3/4 of Transverse colon

Question 36

What structures of the colon does the IMA supply?

Answer 36

Distal 1/4 of transverse colon, Descending colon, Sigmoid colon, Superior rectal artery (terminating branch of IMA)

Question 37

Where does parasympathetic innervation to the colon change and what is the innervation before and after the switch?

Answer 37

Switches at distal end of transverse colon. Proximal to this innervation is vagal, distal to this it is pelvic splanchnic nerves (S2, S3, S4) via inferior hypogastric nerve plexus

Question 38

Give the course of sympathetic innervation to the colon

Answer 38

Preganglionic - Thoracic and lumbar splanchnic nerves (T10 to L2) to superior and inferior mesenteric ganglia. Postganglionic - Follow colic arteries to colon