4. Spleen and the portal venous system.pptx

Question 1

Describe the location of the spleen

Answer 1

Against the diaphragm from ribs 9-11 on the left, and posteriorly.
Its axis along the 10th rib

Question 2

What are the functions of the spleen

Answer 2

Mechanical filtration of RBC
Active immune response through humeral and cell mediated pathways
Haematopoesis until 5th month of gestation

Question 3

What does the gastrosplenic ligament carry

Answer 3

left gastroepiploic and short gastric branches of the splenic arteries (and veins)

Question 4

Describe the course of the splenic artery

Answer 4

Largest branch of coeliac artery
Has a toruous course and it runs along the upper border of the pancreas
The artery then divides into about 6 branches, which enter the spleen at its hilum

Question 5

Describe the course of the splenic vein

Answer 5

Leaves the hilum and runs behind the tail and body of pancreas
Behind the neck of the pancreas it joins the SMV to form the portal vein

Question 6

Describe the lymph drainage of the spleen

Answer 6

Emerge from the hilum and pass through a few lymph nodes along the course of the splenic artery then drain into the coeliac nodes

Question 7

Describe the nerve supply of the spleen

Answer 7

Derived from coeliac plexus - foregut T5-9

Question 8

Describe the course of the portal vein

Answer 8

Formed behind the neck of the pancreas by the union of the splenic vein and the superior mesenteric vein
It ascends to the right behind the first part of the duodenum and enter the lesser omentum
It then runs upwards in front of the opening into the lesser sac to the porta hepatis, where it divides into right and left terminal branches
In the free edge of the lesser omentum, the portal vein lies behind the hepatic artery with the bile duct to the right of the artery

Question 9

Describe the sites of porto-systemic anastomosis and clinical significance

Answer 9

Lower third of oesophagus - oesophageal branches of the left gastric vein anastomose with the oesophageal veins drainging the middle third of the oesophagus into the azygos vein
VARICES

Halfway down the anal canal - the superior rectal veins draining the upper half of the anal canal anastomose with the middle and inferior rectal veins that are systemic tributaries of the interal iliac and internal pudendal veins, respectively
PILES OR HAEMORRHOIDS

The para-umbilical veins - connect the left branch of the portal vein with the superficial veins of the anterior abdominal wall (systemic tributaries). The para-umbilical veins travel in the falciform ligament and may accompany the ligamentum teres
CAPUT MEDUSAE

The veins of the retroperitoneal ascending colon, descending colon, duodenum, pancreas and liver anastomose with the renal, lumbar and phrenic veins

Question 10

What is the normal portal venous pressure

Answer 10

5-10 mmHg

Question 11

What are the supra, hepatic and infra causes of portal hypertension

Answer 11

Supra-hepatic: cardiac disease; hepatic vein thrombosis, IVC thrombosis

Hepatic: cirrhosis

Infra-hepatic: portal vein thrombosis, splenic vein thrombosis

Question 12

Name the visceral branches of the abdominal aorta

Answer 12

3 unpaired branches:
Coeliac trunk T12
Superior mesenteric artery L1
Inferior mesenteric artery L3

Paired branches:
Middle suprarenal arteries
Renal arteries L1/2
Testicular or ovarian arteries L2

Supplying diaphragm or body wall:
Inferior phrenic arteries
Lumbar arteries
Median sacral arteries

Question 13

Describe the inferior vena cava tributaries

Answer 13

2 or 3 anterior visceral tributaries: the hepatic veins

3 lateral visceral tributaries:
right suprarenal vein
both renal veins
right gonadal vein

5 lateral abdominal wall tributaries:
inferior phrenic vein
4 lumbar veins

3 veins of origin:
2 common iliac veins
median sacral vein