Lecture 12 - Alimentary 4 Flashcards
What are the functions of the red and white pulp of the spleen
haemolytic and lymphoid tissue
What differentiates to form the framework of the spleen?
Connective tissue cells (mesenchyme) in the dorsal mesentery of the foetus
What is the spleen prior to fusion?
Several adjoining structures each with their own blood supply
Where does some lobulation remain?
The notching of the external surface especially the superior border
The spleen is a haemopoietic organ, true or false?
No it is initially a haemopoietic organ but later colonised by lymphoid cells
Where does the mature spleen sit anatomically?
Upper left posterior region of stomach between the fundus and the diaphragm
Which ribs is the spleen related to?
9 - 11
What is the long axis of the spleen parallel to?
Rib 10
Which two ligaments is the spleen suspended on
Gastrosplenic and splenorenal
What are the four borders of the spleen?
Superior, inferior, anterior, posterior
Which border of the spleen is often sharper?
The anterior border
What are the two surfaces of the spleen?
Diaphragmatic and visceral
What are the four impressions on the visceral surface of the spleen (and the relationships they indicate)
Gastric (broad, concave impression above the hilus)
Pancreatic (Small, may not be visible)
Colic (Anteriorly below hilus, related to left colic flexure)
Renal (Posterior, below hilus)
Where does the splenic artery meet the spleen?
At the hilus
How does the splenic artery enter the spleen?
The splenic artery terminates in 2-3 branches from which a number of smaller branches enter the substance of the spleen
How is the spleen drained?
By the tributaries of the splenic vein which ultimately drain to the portal vein
What else travels with the blood vessels (2)?
Lymph vessels
Nerves also travel as a plexus on arteries
What are the 5 functions of the liver?
Exocrine, endocrine, metabolism, detoxification and haemopoiesis
What cell type is the liver made up of?
Hepatocyte
As an exocrine organ, what does the liver release?
Bile
What is the function of bile?
Digestion especially fats, contains pigments from the breakdown of RBC in the spleen
As an endocrine gland what does the liver release?
Glucose, plasma and proteins into theblood
What does the liver metabolise?
Protein and carbohydrates
Where is the liver located?
Under the right ribs and diaphragm
Where does the liver extend to and from?
From the level of the 5th rib to the costal margin
Where does the gallbladder protrude from?
Its lower surface at about the level of the 9th costal cartilage and linea semilunaris
What are the two surfaces of the liver?
Diaphragmatic and visceral
The entire liver is covered in peritoneum true or false?
False, it is covered with peritoneum except at sites of attachments of the ligaments
What are the four anatomical lobes of the liver
left, right, caudate and quadrate
How are the functional lobes of the liver divided?
On the basis of supply by right or left hepatic arteries. The right is separated from the left by a lien drawn up through the fossa for the gallbladder
What does the left functional liver include?
Left lobe + caudate and quadrate lobes
What are the components of the liver’s dual blood supply
1) nutrient rich and oxygen poor blood from the portal vein
2) oxygen rich blood from hepatic artery proper
How is the liver drained?
By hepatic veins into the IVC - 3 upper large veins and a variable number of lower veins
The liver is retroperitoneal, true or false?
False
All the ligaments suspending the liver are interconnected true or false?
True
What are the four ligaments that suspend the liver?
Coronary, left and right triangular, falciform
What parts of the diaphragm is the liver attached to and by what ligaments?
Right dome and central tendon by the coronary. left and right triangular ligaments
What is the ‘bare area’
A region in isolated livers under the attachment of the triangular ligaments which is free from peritoneum
What is the falciform ligament derived from?
Ventral mesentery
Where does the falciform ligament extend from?
The anterior surface of the liver to anterior abdominal wall down to the level of umbilicus. The ligamentum teres in the lower edge runs to the umbilicus.
What is the relationship between the lesser omentum and the liver?
It surrounds the porta hepatis and then superiorly into fissure to give ligamentum venosum and finally is attached to the diaphragm and surrounds oesophagus.
Where are the fissures of the liver?
On the posterior aspect and they separate the left lobe from caudate and quadrate lobes
Where is the fissure for the ligamentum venosum?
Between the left lobe and caudate lobe
Where is the fissure for the ligamentum teres?
Between the left lobe and the quadrate lobe
What is the region between fissures?
Porta hepatis
What is the porta hepatis?
It is the hilus of the liver where blood vessels, nerves, lymphatics and the hepatic bile duct enter or leaves the liver
What does the porta hepatis separate?
The caudate and quadrate lobes and marks the lower edge of the lesser omentum
What are the ligaments remnants of?
The fetal left umbilical vein
What does the umbilical vein do?
It mostly bypasses the liver and goes straight to the foetal IVC
What becomes the ligamentum teres?
The part of the umbilical vein between umbilicus and the left branch of portal vein
What becomes the ligamentum venosum?
The part of the left branch of portal vein and the IVC
Where does the ligamentum teres run?
From the umbilicus to the liver in the free inferior border of the falciform ligament. From there it passes into the fissure for ligamentum teres.
Ligamentum teres remains functional as a vessel under normal circumstances postnatally, true or false?
False
The ligamentum venosum is a continuation of ligamentum teres true or false?
True
What are the functions of the gallbladder (3)?
Store, concentrate and transport bile
What are the three parts of the gallbladder?
Fundus, body, neck
Where is the fundus of the gallbladder
Below the lower margin of liver
What does the lining mucosa of the gallbladder do?
Take up water and solutes from bile
What are the 5 ducts of the gallbladder?
Left and right hepatic ducts, main hepatic duct, cystic duct and bile duct
What forms the main hepatic duct?
The left and right hepatic ducts emerging from the liver
What forms the bile duct
The joining of the main hepatic duct and cystic duct
Where does the bile duct travel?
Through the free edge of the lesser omentum, behind the first part of the duodenum then on the posterior surface of the head of the pancreas to come into close proximity to the main pancreatic duct
What do the bile duct and main pancreatic duct fuse to form?
The hepatopancreatic ampulla
Where do the bile and main pancreatic ducts empty?
Greater duodenal papilla
