The Liver

Question 1

What is the anatomical position of the liver?

Answer 1

The liver is predominantly located in the right hypochondrium and epigastric areas, and extends into the left hypochondrium.

Question 2

describe the falciform ligament

Answer 2

• sickle-shaped ligament attaches the anterior surface of the liver to the anterior abdominal wall.
• its free edge contains the ligamentum teres (round ligament), a remnant of the umbilical vein.

Question 3

describe the coronary ligament (anterior and posterior folds) of the liver

Answer 3

• attaches the superior surface of the liver to the inferior surface of the diaphragm and demarcates the bare area of the liver.
• the anterior and posterior folds unite to form the triangular ligaments on the right and left lobes of the liver.

Question 4

what is the function of the triangular ligaments (left and right) of the liver

Answer 4

• Attaches the left lobe of the liver to the diaphragm.
• Attaches the right lobe of the liver to the diaphragm.

Question 5

describe the lesser omentum, what ligaments does it consist of?

Answer 5

• attaches the liver to the lesser curvature of the stomach and first part of the duodenum.
• it consists of the hepatoduodenal ligament and the hepatogastric ligament.

Question 6

hepatoduodenal ligament location

Answer 6

surrounds the portal triad

Question 7

how is the posterior surface of the liver secured to the IVC?

Answer 7

hepatic veins and fibrous tissue

Question 8

label this

Answer 8

Question 9

where is the caudate lobe located

Answer 9

• located on the upper aspect of the visceral surface.
• it lies between the IVC and a fossa produced by the ligamentum venosum.

Question 10

what is the anatomical position of the quadrate lobe

Answer 10

• located on the lower aspect of the visceral surface.
• lies between the gallbladder and a fossa produced by the ligamentum teres (round ligament).

Question 11

function of porta hepatis

Answer 11

• transmits all the vessels, nerves and ducts entering or leaving the liver with the exception of the hepatic veins.

Question 12

what are the structural units of the liver called?

Answer 12

lobules

Question 13

what does the portal triad consist of?

Answer 13

arteriole - a branch of the hepatic artery entering the liver.
venule - a branch of the hepatic portal vein entering the liver.
bile duct - a branch of the bile duct leaving the liver.

Question 14

label this hepatic lobule

Answer 14

Question 15

describe the dual bloody supply of the liver

Answer 15

Hepatic artery proper (25%):
- supplies the non-parenchymal structures of the liver with arterial blood. It is dervied from the coeliac trunk.

Hepatic portal vein (75%):
- supplies the liver with partially deoxygenated blood, carrying nutrients absorbed from the small intestine.
- dominant blood supply to the liver parenchyma, allows the liver to perform its gut-related functions, such as detoxification.

Question 16

how is venous drainage of the liver achieved?

Answer 16

• through hepatic veins.
• the central veins of the hepatic lobule form collecting veins which then combine to form multiple hepatic veins.
• these veins then open into the IVC.

Question 17

label this venous portal system

Answer 17

Question 18

describe the nerve supply of the liver

Answer 18

• the parenchyma of the liver is innervated by the hepatic plexus, which contains sympathetic (coeliac plexus) and parasympathetic (vagus nerve) nerve fibres.
• these fibres enter the liver at the porta hepatis and follow the course of branches of the hepatic a and v.

Question 19

what nerves innervate the Glisson’s capsule (fibrous covering of the liver)?

Answer 19

branches of the lower intercostal nerves

Question 20

describe the lymphatic drainage of the liver

Answer 20

• lymph vessels of anterior aspect of liver drain into hepatic lymph nodes > coeliac lymph nodes > cisterna chyli.
• lymph vessels from posterior aspect of liver drain into phrenic and posterior mediastinal lymph nodes > right lymphatic and thoracic ducts.

Question 21

which structures are present in the porta hepatis?

Answer 21

portal vein
hepatic artery
hepatic nervous plexus
hepatic ducts
lymphatic vessels

Question 22

which structures are in the portal triad?

Answer 22

• arteriole (branch of hepatic artery entering the liver).
• venule (branch of hepatic portal vein entering the liver).
• bile duct (branch of bile duct leaving the liver).

Question 23

where does the central vein drain to?

Answer 23

into hepatic veins that go into the IVC.