Stroke

Question 1

Blood supply to the brain?

Answer 1

2 internal carotid arteries

2 vertebral arteries

Question 2

What is the circle of willis?

Answer 2

A circle of arteries that supply blood to the brain. Anterior cerebral artery (left and right)
Anterior communicating artery
Internal carotid artery (left and right)
Posterior cerebral artery (left and right)
Posterior communicating artery (left and right)
The basilar artery and middle cerebral arteries, supplying the brain, are also considered part of the circle.

Question 3

What is the physiological significance of the circle of willis?

Answer 3

Occlusion of one internal carotid does not necessarily result in stroke. Other Blood vessels can often preserve cerebral perfusion well enough to a old ischaemia.

Question 4

What is an ischaemic stroke?

Answer 4

A stroke due to the occlusion either as a result of atheroma in the artery itself or secondary to an emboli from atheromatons MI or neck vessels.

Question 5

Define CVA

Answer 5

A cerebral vascular accident is a rapidly developed clinical sign of focal disturbance of the cerebral function of presumed vascular origin and of more than 24 hours.

Question 6

What is a subarachnoid haemorrhage ?

Answer 6

An SAH is a bleeding into the subarachnoid space ( between the inner 2 layers if the meninges usually filled with CSF) usually arising from the rupture of an aneurysm ( abnormal ballooning of a cerebral artery usually due to congenital or acquired weakness in the wall of the vessel) situated at or near the circle of Willis. Most common is ACA, PCA and MCA. Associated with sudden intense headache, vomiting, neck stiffness and loss of consciousness.

Question 7

What does the ACA supply?

Answer 7

Frontal lobe

Medial part of the sensorimotor cortex

Question 8

PCA?

Answer 8

Occipital lobe
Medial aspect of the temporal lobe
Thalamus

Question 9

MCA?

Answer 9

Outer surface
Sensorimotor cortex
Basal ganglia
Internal capsule
Broca's area

Question 10

Basilar artery?

Answer 10

All if the brainstem
Cerebellum
Nuclei of cranial nerves

Question 11

Prognosis?

Answer 11

Good if act fast. People can be left with hemiparesis or hemiplegia

Question 12

Explain recovery from stroke?

Answer 12

Initially- resolution of oedema and diaschisis
Neuroplasticity- the adaptive capability of the CNS and its ability to modify its own structural organisation and functioning.
Many pathways lies dormant having minimal effect. After removal of a primary pathway dormant pathways become more effective and stronger with more use I.e. practicing an activity. Formation of new synapses and collateral sprouting.

Question 13

Surgical intervention for SAH

Answer 13

Surgical clipping, open brain surgery and the placing of a small metallic clip across the base of the aneurysm preventing bloody flow into the weakened area or
Embolisation where metal coil or balloons are introduced into the artery to block off the aneurysm.