T1 L6 Anatomy of the liver

Question 1

How much does the liver weigh?

Answer 1

1.4-1.6kg

Question 2

Where is the liver?

Answer 2

Below the diaphragm
Mostly in right hypochondriac & epigastrium
On right w.r.t the stomach
Above colon
Overlies gallbladder

Question 3

What are the main functions of the liver?

Answer 3

Detoxification
Protein synthesis
Production of bile - accessory GI organ
Glycogen storage

Question 4

Where is the falciform ligament?

Answer 4

In the midline & attaches the liver to the anterior abdominal wall
Ligamentum teres is at the lower end

Question 5

What are the 4 lobes of the liver?

Answer 5

Left lobe
Right lobe
Quadrate
Caudate

Question 6

What is the round ligament?

Answer 6

Obliterated left umbilical vein

Extends to umbilicus

Question 7

What is the coronary ligament?

Answer 7

Links diaphragm to liver

Question 8

What is the lesser omentum?

Answer 8

Links liver to stomach
From lesser curvature of stomach to aorta hepatis
Has a free margin
Close to stomach & encloses gastric arteries & veins

Question 9

What does the lesser omentum enclose?

Answer 9

Hepatic artery
Portal vein
Bile duct
Lymph vessels

Question 10

What supplies blood to the liver?

Answer 10

Hepatic artery

Question 11

Give some hepatic artery variations

Answer 11

Right hepatic artery replaced by superior mesenteric artery
Left hepatic artery replaced by left gastric artery
Trifurcation of common hepatic artery - right hepatic artery, left hepatic artery, gastroduodenal artery

Question 12

What is the porta hepatis?

Answer 12

At hilum of liver - visceral surface

Deep fissure

Question 13

What enters/exits through the porta hepatis?

Answer 13

Hepatic portal vein
Hepatic artery proper
Common hepatic duct
Nerves & lymphatics

Question 14

What is a liver lobule?

Answer 14

Functional unit of the liver
Hexagon shaped
Contains hepatocytes
Hepatocytes secrete bile
Portal triad at corners

Question 15

How are the anatomical lobes divided?

Answer 15

According to how hepatic artery & portal vein subdivides
Branches of hepatic artery & portal vein carry blood into sinusoids
Branches of bile duct accompany those of hepatic artery & portal vein

Question 16

What do hepatocytes do?

Answer 16

Synthesise & release plasma proteins into blood albumin
Deaminates amino acids - urea into blod
Bilirubin to bile pigments
Bile salts - emulsification of fats

Question 17

What is the venous drainage of the liver?

Answer 17

Mixed blood from 2 sources (portal & hepatic) into the sinusoids passes through hepatocytes & into central vein

Question 18

Describe the central vein

Answer 18

Found at centre of hepatic lobule
Drains into sub lobular vein
Sublobular veins drain into hepatic veins
Hepatic veins drain into inferior vena cava

Question 19

What are portal systemic anastomosis?

Answer 19

Communications between some branches of the portal & systemic systems
Important if portal vein is blocked or the passage via the liver meets resistance - portal hypertension. Allows collateral return of blood to heart

Question 20

What is the anastomosis of the abdominal part of the oesophagus?

Answer 20

Left gastric tributaries with oesophageal branches azygos

Question 21

What is the anastomosis of the anal canal?

Answer 21

Superior rectal anastomoses with middle & inferior rectal

Question 22

What is the anastomosis of the umbilicus?

Answer 22

Paraumbilical veins with epigastric veins

Question 23

What is portal hypertension?

Answer 23

Common clinical condition
Obstruction of portal vein –> increase in pressure –> hypertension
Anastomoses between portal & systemic means back flow of blood to heart & then lungs
Varicoses
Caput medusa

Question 24

What is a portacaval shunt?

Answer 24

Reduction of hypertensions
Diverts blood from portal to systemic
Used less frequently since the creation of TIPS

Question 25

What is bile?

Answer 25

Secreted by hepatocytes into bile canaliculi
40ml/hour
Closed sphincter Oddi to duodenum –> bile flows to gallbladder to be stored & concentrated

Question 26

Describe the lymphatic drainage

Answer 26

Lymph nodes in porta hepatis
Pass to coeliac nodes
Drain to cisterna chyli

Question 27

Describe liver trauma

Answer 27

Closely related to lower ribs
Fracture ribs / penetrating wounds
High vascularisation –> severe haemorrhage