Duodenum (Dave's notes)

Question 1

Describe the duodenum

Answer 1

A c shaped tube around the head of the pancreas

Question 2

Where does the first 2cm of the duodenum lie? What about the rest of the duodenum?

Answer 2

The first two cm of the duodenum lies between the greater and lesser sacs. The rest of the duodenum is retroperitoneal

Question 3

Describe the length and course of the superior first part of the duodenum

Answer 3

• 2 inches
• Runs to the right and backwards/posterior

Question 4

Describe the length and course of the descending second part of the duodenum

Answer 4

• 3 inches
• To the right of L2
• the second part of the duodenum curves downwards over the hilum of the right kidney

Question 5

Describe the relations of the second part of the duodenum

Answer 5

• D2 curves over the hilum of the right kidney.
• The bile duct lies at the posteromedial wall.
• D2 lies in both supra and infracolic compartments

Question 6

Describe the length, course, and relations of the horizontal third part of the duodenum

Answer 6

• 4 inches
• runs from right to left across L3
• Lies on the aorta at the commencement of the IMA, and is crossed by the SMA.
• Lies in both left and right infracolic compartments.

Question 7

Describe the length and course of the ascending fourth part of the duodenum

Answer 7

• 1 inch
• to the left of L2 ascends to the left of the aorta
• on the left psoas which fixes the DJ flexure

Question 8

Name the four parts of the duodenum

Answer 8

• D1 1st superior
• D2 2nd descending
• D3 3rd horizontal
• D4 4th ascending part

Question 9

Describe the lining of the duodenum

Answer 9

The duodenum’s internal mucous membrane is thrown into numerous circular folds

Question 10

Name the duodenal recessed and their locations

Answer 10

Formed around D4 and duodenojejunal junction

1. superior duodenal recess - left L2
2. inferior duodenal recess - left L3
3. retroduodenal recess - largest if present
4. paraduodenal recess - newborn
5. duodenojejunal recess - pancreas, kidney left, renal vein below
6. mesentericoparietal recess - below D3

Question 11

What is the blood supply of the duodenal artery?

Answer 11

From the superior and inferior pancreaticoduodenal arteries

• superior pancreaticoduodenal artery - GDA
• inferior pancreaticoduodenal artery - SMA

Question 12

The first 2cm of the duodenum may receive blood supply from which arteries?

Answer 12

Common hepatic, gastroduodenal, superior pancreaticoduodenal, right gastric, right gastroepiploic

Question 13

What is the lymphatic drainage of the duodenum?

Answer 13

The lymphatic drainage of the duodenum is via channels accomanying the superior and inferior pancreaticoduodenal arteries to the coeliac trunk and SMA nodes