Duodenum

Question 1

Characteristics of the duodenum

Answer 1

Shortest, widest and most fixed part of the small intestine

Question 2

Location of the duodenum

Answer 2

Above the level of umbilicus
Opposite first, second and third lumbar vertebrae

Question 3

What are the four parts of the duodenum?

Answer 3

First or superior part is 5 cm or 2 inches long
Second or descending part is 7.5 cm or 3 inches long
Third or horizontal part is 10 cm or 4 inches long
Fourth or ascending part is 2.5 cm or 1 inch long

Question 4

Which parts of the duodenum are covered with peritoneum?

Answer 4

The duodenum is mostly retroperitoneal and fixed
However, at its two ends it is suspended by folds of peritoneum, and is, therefore, mobile
Anteriorly, the duodenum is only partly covered with peritoneum

Question 5

Course of the first part of the duodenum?

Answer 5

Begins at the pylorus, and passes backwards, upwards and to the right to meet the second part at the superior duodenal flexure

Question 6

What are the peritoneal relations of the first part of the duodenum?

Answer 6

The proximal 2.5 cm is movable. It is attached to the lesser omentum above, and to the greater omentum below.
The distal 2.5 cm is fixed. It is retroperitoneal. It is covered with peritoneum only on its anterior aspect.

Question 7

First part of duodenum: Visceral anterior relations

Answer 7

Quadrate lobe of liver, and gallbladder

Question 8

First part of duodenum: Visceral posterior relations

Answer 8

Gastroduodenal artery, bile duct and portal vein

Question 9

First part of duodenum: Visceral superior relations

Answer 9

Epiploic foramen

Question 10

First part of duodenum: Visceral inferior relations

Answer 10

Head and neck of the pancreas

Question 11

Course of the second part of the duodenum?

Answer 11

7.5 cm long
Begins at the superior duodenal flexure, passes downwards to reach the lower border of the third lumbar vertebra, where it curves towards the left at the inferior duodenal flexure, to become continuous with the third part

Question 12

What are the peritoneal relations of the second part of the duodenum?

Answer 12

It is retroperitoneal and fixed
Its anterior surface is covered with peritoneum, except near the middle, where it is directly related to the colon

Question 13

Second part of duodenum: Visceral anterior relations

Answer 13

Right lobe of the liver
Transverse colon
Root of the transverse mesocolon
Small intestine

Question 14

Second part of duodenum: Visceral posterior relations

Answer 14

Anterior surface of the right kidney near the medial border
Right renal vessels
Right edge of the inferior vena cava
Right psoas major

Question 15

Second part of duodenum: Visceral medial relations

Answer 15

Head of the pancreas
The bile duct

Question 16

Second part of duodenum: Visceral lateral relations

Answer 16

Right colic flexure

Question 17

What special features are seen in the second part of the duodenum?

Answer 17

Major duodenal papilla
Minor duodenal papilla
Plica longitudinalis

Question 18

What is the major duodenal papilla?

Answer 18

Elevation present posteromedially, 8 to 10 cm distal to the pylorus

Question 19

What opens into the summit of the major duodenal papilla?

Answer 19

Hepatopancreatic ampulla

Question 20

Where is the minor duodenal papilla?

Answer 20

Present 6 to 8 cm distal to the pylorus

Question 21

What opens into the minor duodenal papilla?

Answer 21

Opening of the accessory pancreatic duct.

Question 22

What is the plica longitudinalis?

Answer 22

A longitudinal fold seen below the major duodenal papilla

Question 23

Course of the third part of the duodenum

Answer 23

10 cm long
It passes almost horizontally and slightly upwards in front of the inferior vena cava, and ends by joining the fourth part in front of the abdominal aorta

Question 24

Peritoneal relations of third part of duodenum

Answer 24

Retroperitoneal and fixed
Its anterior surface is covered with peritoneum, except in the median plane, where it is crossed by the superior mesenteric vessels and by the root of the mesentery

Question 25

Third part of the duodenum: Visceral anterior relations

Answer 25

Superior mesenteric vessels Root of mesentery

Question 26

Third part of the duodenum: Visceral posterior relations

Answer 26

Right ureter Right psoas major Right testicular or ovarian vessels Inferior vena cava Abdominal aorta with origin of inferior mesenteric artery

Question 27

Third part of the duodenum: Visceral superior relations

Answer 27

Head of the pancreas with uncinate process

Question 28

Third part of the duodenum: Visceral inferior relations

Answer 28

Coils of the jejunum

Question 29

Course of the fourth part of the duodenum

Answer 29

2.5 cm long It runs upwards on or immediately to the left of the aorta, up to the upper border of the second lumbar vertebra, where it turns forwards to become continuous with the jejunum at the duodenojejunal flexure

Question 30

Peritoneal relations of the fourth part of the duodenum

Answer 30

Mostly retroperitoneal being covered with peritoneum only anteriorly

Question 31

Fourth part of the duodenum: Visceral anterior relations

Answer 31

Transverse colon Transverse mesocolon Lesser sac Stomach

Question 32

Fourth part of the duodenum: Visceral posterior relations

Answer 32

Left sympathetic chain Left renal artery Left gonadal artery Inferior mesenteric vein

Question 33

Fourth part of the duodenum: Visceral lateral relations

Answer 33

**To the right**: Attachment of the upper part of the root of the mesentery **To the left**: Left kidney Left ureter

Question 34

Fourth part of the duodenum: Visceral superior relations

Answer 34

Body of pancreas

Question 35

What is the suspensory muscle of the duodenum/ligament of Treitz?

Answer 35

Fibromuscular band Suspends and supports the duodenojejunal flexure Normally, its contraction increases the angle of the duodenojejunal flexure

Question 36

Location of the Suspensory Ligament of Treitz?

Answer 36

Arises from the right crus of the diaphragm, close to the right side of the oesophagus, passes downwards behind the pancreas, and is attached to the posterior surface of the duodenojejunal flexure and the third and fourth parts of the duodenum

Question 37

Arterial supply of the duodenum?

Answer 37

Up to major duodenal papillae: Supplied by the superior pancreaticoduodenal artery Below major duodenal papillae: Supplied by inferior pancreaticoduodenal artery

Question 38

Venous drainage of duodenum?

Answer 38

Veins of the duodenum drain into the splenic, superior mesenteric and portal veins

Question 39

Lymphatic drainage of duodenum?

Answer 39

Pancreaticoduodenal nodes Hepatic nodes Coeliac nodes Cisterna chyli

Question 40

Nerve supply of duodenum

Answer 40

**Sympathetic nerves**: T9 and T10 **Parasympathetic nerves**: Vagus

Question 41

What is the duodenal cap?

Answer 41

A triangular shadow demarcating the first part of the duodenum in a skiagram taken after eating a barium meal

Question 42

Common location for peptic ulcer formation in duodenum?

Answer 42

First part of duodenum because of exposure to acidic contents of the stomach