ILA6 - Jaundice Flashcards
(72 cards)
What is the liver an embryological derivative of?
Foregut which develops in the ventral mesentry
Which parts of the abdomen does the liver lie in?
The two hypochondria and the epigastric regions
What are the two coverings of the liver and in what directions do they lie?
Diaphragm (superior, anterior and posterior, areas not covered by peritoneum = bare area) and visceral peritoneum (inferior)
What is Glisson’s capsule?
Fibrous covering of the liver and en-sheaths the portal triad. It is innervated by the lower intercostal nerves, distension results in sharp pain.
What are the associated ligaments of the liver?
a) Falciform ligament. Umbilicus (ant abdo wall) to liver, contains ligamentus teres (remnant of umbilical vein)
b) Ligamentum teres. Passes into a fissure on the visceral surface and join the L branch of the portal vein in the porta hepatis.
c) Ligamentum venosum. Fibrous band that is the remains of the ductus venosus (bypass of liver in the fetus), is attached to the L branch of the portal vein and ascends in a fissure on the visceral surface to be attached above to the IVC.
What do folds of peritoneum connect the liver to?
- Stomach (hepatogastric ligament)
- The duodenum (hepatoduodenal ligament) (both contained within the lesser omentum)
- The diaphragm (right and left triangular ligaments and anterior and posterior coronary ligaments) (on R lobe)
What are the lobes of the liver?
left, right, caudate and quadrate
What separates the left and right lobes of the liver?
Falciform ligament
What borders the caudate lobe?
On the left by the fissure for the ligamentum venosum and on the right by the groove for the inferior vena cava. superior.
What borders the quadrate lobe?
On the left by the fissure for ligamentum teres and on the right by the fossa for the gallbladder. inferior.
What is contained within the porta hepatis?
R and L hepatic ducts.
R and L branches of hepatic artery
Portal vein
Sympathetic and parasympathetic nerve fibres.
What is the arterial blood supply of the liver?
Hepatic artery (L&R)
What is the venous blood supply to the liver?
- The portal vein divides into R and L terminal branches that enter the porta hepatis behind the arteries.
- The hepatic veins (3 or more) emerge from the posterior surface of the liver and drain into the IVC.
What is contained in the portal triad?
Hepatic artery (25% of blood supply to liver), portal vein (75% blood supply) and bile duct. ALso contains nerves and lymphatics.
What are the two methods of classifying groups of cells in the liver?
Lobules (hexagon) and acinus (functional unit and diamond shape)
How does the blood reach the hepatic vein?
- Arterial and venous blood is conducted to the centre of each liver lobule by the liver sinusoids.
- The central veins drain into the R and L hepatic veins which open directly into the IVC
Which cells in the acini do which jobs?
Ones closer to arteries (portal triad) perform activities requiring oxygen, further away cells perform drug metabolism
What is the lymphatic drainage of the liver?
Lymph nodes in the porta hepatis then to the coeliac nodes
What is the nerve supply to the liver?
- Sympathetic and parasympathetic nerves form the coeliac plexus.
- The anterior vagal trunk gives rise to a large hepatic branch which passes directly to the liver
What are the parts of the gall bladder?
- A rounded end (fundus of gallbladder), which may project from the inferior border of the liver, comes into contact with the anterior abdominal wall at level of 9th costal cartilage
- A major part in the fossa (body of gallbladder), which may be against the transverse colon and the superior part of the duodenum
- A narrow part (neck of gallbladder) with mucosal folds forming the spiral fold
What is the order of veins in the liver?
Central vein, collecting vein, hepatic vein and the IVC
What is the function of the gall bladder?
a) The gallbladder receives, concentrates, and stores bile from the liver.
b) Bile is delivered to the duodenum as the result of contraction and partial emptying of the gallbladder.
c) This mechanism is initiated by entrance of fatty foods into the duodenum: the fat causes release of cholecystokinin from the mucous membrane of the duodenum – the hormone then enters the blood, causing the gallbladder to contract. At the same time, the smooth muscle around the distal end of the bile duct and ampulla is relaxed, thus allowing the passage of concentrated bile into the duodenum.
What is the blood supply to the gall bladder?
The arterial supply to the gallbladder is the cystic artery from the right hepatic artery (a branch of the hepatic artery proper)
The cystic veins drain directly into the portal vein
What is the order for the duct system of the bile?
a) Bile canaliculi
b) Interlobular ducts (larger and larger)
c) R and L hepatic ducts (at porta hepatis
d) Common hepatic duct – descends within the free margin of lesser omentum.
e) Cystic duct joins common hepatic duct from the R side to form the bile duct:
- First part of its course: lies in R free margin of lesser omentum
- Second part of its course: lies behind first part of duodenum
- Third part of its course: lies in a groove on posterior surface of head of the pancreas. Here it comes into contact with the main pancreatic duct.
f) Ends by piercing the medial wall of the second part of the duodenum about halfway down its length. Joined by main pancreatic duct – together they open into the ampulla of Vater which opens into the duodenum by means of the duodenal papilla. Terminal parts of both ducts and the ampulla are surrounded by circular muscle known as the sphincter of Oddi.
