Anatomy

Question 1

What is the blood supply to the cervical oesophagus?

Answer 1

Inferior thyroid artery + veins to SVC

Question 2

What is the blood supply to the thoracic oesophagus?

Answer 2

Thoracic aortic branches + azygous system

Question 3

What is the blood supply to the abdominal oesophagus?

Answer 3

Coeliac plexus from the last gastric artery
Left gastric vein to portal system

Question 4

What are the diaphragmatic hiatuses?

Answer 4

Aortic opening = at T12
Oesophageal opening = at T10
Caval opening = at T8

Question 5

How do hiatus hernias form?

Answer 5

The oesophageal sphincter dilates (as it is only physiological/ functional, not anatomical, it does not have its own innervation)

Question 6

Describe the branches of the abdominal aorta

Answer 6

1. Phrenic arteries
2. Coeliac trunk - left gastric, common hepatic and splenic arteries
3. Superior mesenteric
4. Suprarenal and renal arteries
5. Gonadal arteries
6. Inferior mesenteric

Question 7

What are the parts of the stomach?

Answer 7

Cardia, fundus, body and pylorus into the duodenum

Question 8

Describe the arterial supply of the stomach

Answer 8

Left gastric along lesser curvature and up to oesophagus
Right gastric (from hepatic artery) also along lesser curvature
Right gastro-epiploic (from hepatic) and left gastro-epiploic (from splenic) along greater curvature
Short gastric arteries (from splenic) to the fundus

Question 9

What are the parts of the duodenum? Which are retroperitoneal?

Answer 9

Superior, descending, inferior and ascending
Descending to ascending are retroperitoneal

Question 10

Describe the arterial supply of the duodenum

Answer 10

Gastroduodenal from right hepatic artery - becomes superior pancreaticoduodenal
Inferior pancreaticoduodenal from superior mesenteric artery

Question 11

Where is bile formed and stored?

Answer 11

Bile is formed in the liver and stored in the bile duct

Question 12

Describe the biliary tree

Answer 12

Left and right hepatic ducts form the common hepatic duct
Cystic duct from the gallbladder joins the common hepatic duct to form the common bile duct
The pancreatic duct joins just before entering the duodenum via the major duodenal papilla

Question 13

What is Calot’s triangle?

Answer 13

Formed by the common hepatic duct, cystic duct and inferior surface of the liver

Question 14

What is the ‘foregut’ and what is its arterial supply?

Answer 14

Stomach up to the 2nd part of the duodenum
Supplied by the coeliac trunk

Question 15

What is the ‘midgut’ and what is its arterial supply?

Answer 15

From 2nd part of the duodenum to splenic flexure (on the transverse colon)
Supplied by the SMA

Question 16

What are the branches of the SMA?

Answer 16

Inferior pancreaticoduodenal
Ileocolic
Right and middle colic

Question 17

What is the ‘hindgut’ and what is its arterial supply?

Answer 17

From splenic flexure to the superior rectum
Supplied by the IMA

Question 18

What are the branches of the IMA?

Answer 18

Left colic
Sigmoid, which gives off the superior rectal

Question 19

Why is the splenic flexure prone to ischaemia?

Answer 19

It is a ‘watershed’ region, dependent on the marginal artery to branch between the midgut and foregut regions

Question 20

Describe the rectal blood supply

Answer 20

Superior 1/3rd = superior rectal artery from IMA
Middle 1/3rd = middle rectal artery from internal iliac
Inferior 1/3rd = inferior rectal artery from internal pudendal

Question 21

What are the sites of portosystemic circulation?

Answer 21

Lower 1/3rd of oesophagus (azygous veins meet left gastric)
Umbilicus (umbilical vein meets epigastric)
Upper anal canal (superior rectal meets middle/ inferior rectal)