Bloody supply to the brain & stroke

Question 1

Why is CONTINUOUS bloody supply to the brain so important?

Answer 1

Brain cells = highest energy needs

Cells in the cortex are HIGHLY susceptible to oxygen deprivation and therefore die quickly.

Question 2

Where does bloody supply to the brain begin?

Answer 2

The aorta

Question 3

What are the two pairs of arteries that supply blood to the brain

Answer 3

Internal carotids (left and right) take 80%
Vertebral arteries supply 20%

Question 4

Which arteries supply the anterior part of the brain?

Answer 4

The internal carotids

Question 5

Which arteries supply the posterior part of the brain?

Answer 5

The vertebral arteries

Question 6

Where do the vertebral arteries converge? What forms?

Answer 6

At the brainstem

The bailer artery forms (which supplies the brain stem)

Question 7

What does the Basilar artery split into?

Answer 7

The left and right posterior cerebral arteries

Question 8

What do the internal carotids split into?

Answer 8

The anterior and middle cerebral arteries

Question 9

What area of the brain is supplied by the posterior cerebral arteries?

Answer 9

The occipital lobe

Question 10

Which area of the brain is supplied by the middle cerebral artery?

Answer 10

Entire lateral surface of the brain

• language regions
• primary motor and sensory cortex

Therefore blockage = extensive damage

Question 11

What is the purpose of the Circle of Willis?

Answer 11

Co-lateral supply - It allows some blood supply even if there’s a blockage

Question 12

Which area of the brain is supplied by the anterior cerebral artery?

Answer 12

Pre-frontal cortex - higher order thinking/functions
Lower limbs (leg and foot)

Question 13

Which area of the brain is supplied by the posterior cerebral artery?

Answer 13

Medial temporal lobe (contains hippocampus)
Part of the temporal lobe and the occipital lobe
- Damage to visual areas = blindness/alexia

Question 14

Which area of the brain is supplied by the vertebral artery?

Answer 14

Medulla and cerebellum

Question 15

Define stroke

Answer 15

A vessel of the brain either bleeds or is blocked, causing part of the brain to be deprived of oxygen

Question 16

What is an ischemic stroke?

Answer 16

Lack of blood flow to the brain tissue depriving it of the oxygen/nutrients it needs

Question 17

What is a haemorrhagic stroke?

Answer 17

The bleeding of a vessel, which releases blood into the brain and intracranial spaces.
Causes localised and generalised pressure on brain tissue

Question 18

What is a thrombosis?

Answer 18

Obstruction of blood flow due to localised occlusive processes - i.e. the vessel narrows so much that blood can no longer flow through

Question 19

What is an embolism?

Answer 19

Material from elsewhere in the blood system lodges in an artery and blocks blood flow

Question 20

What is an intracerebral haemorrhage?

What are some of the causes?

Answer 20

Bleeding from a blood vessel WITHIN the brain

High BP weakens artery walls - greater chance of vessel bursting

Question 21

What is an aneurysm?

Answer 21

Ballooning of the artery to form a “sack” where blood gathers. If the aneurysm bursts, a haemorrhage results

Question 22

What is a TIA?

Answer 22

Transient Ischemic Attack
"mini stroke"
Temporary blockage of a brain vessel
Symptoms last from seconds - 24 hours
Still a medical emergency - could be a warning sign of a larger stroke on the way

Question 23

Why is early intervention important in stroke rehabilitation?

Answer 23

The surrounding brain tissue can be recovered with quick and effective treatment