LO4 Stroke assessment

Question 1

What is the WHO definition of a stroke?

Answer 1

A neurological insult of sudden onset lasting for >24 hours with focal rather than global cerebral dysfunction. In which after adequate investigations, symptoms are presumed to be of non-traumatic vascular origins.

Question 2

What is the difference between a stroke and a TIA?

Answer 2

A TIA lasts less than 24 hours

Question 3

What are the two types of stroke? What percentage of strokes is each one?

Answer 3

Ischaemic 80%

Haemmorhagic 10-15%

Question 4

In ischaemic stroke what is the difference between the core and the penumbra?

Answer 4

In the ischaemic core there is complete metabolic failure due to severely reduced perfusion (<10ml/min/100g). In the penumbra there is only reduced perfusion and so this tissue is still salvageable. This ideally needs to occur within 4-6 hours.

Question 5

What are the 4 major causes of ischaemic stroke?

Answer 5

Large artery arterio-thrombosis, Cardio-embolism, Lacunar infarcts, cryptogenic strokes.

Question 6

What are the most common areas for arteriothrombosis to occur?

Answer 6

At the bifurcation of the CCA and at the origin of the ICA

Question 7

What are the potential causes of cardioembolism?

Answer 7

AF, MI, endocarditis

Question 8

What is a lacunar infarct? What are the common risk factors for lacunar stroke?

Answer 8

Occlusion of the small perforating arteries deep within the white matter and brainstem. Risk factors include HTN, diabetes and hyperlipidaemia

Question 9

What is the best imaging modality for ischaemic stroke?

Answer 9

Diffusion weighted MRI

Question 10

How do ischaemic strokes appear on CT scanning?

Answer 10

Initially the changes are very subtle but over the course of days there will be hypoattenuation over the area of ischaemia

Question 11

What are the two types haemorrhagic stroke? (anatomical location)

Answer 11

Intracerebral or subarachnoid

Question 12

What are the most common causes of primary intracerebral haemorrhage?

Answer 12

Chronic hypertensio- Formation of microaneurysms that are prone to rupture; typically rupture of deep perforating arteries.
Amyloid angiopathy- Deposition of amyloid proteins within blood vessels; typically causing multiple superficial haemorrhages

Question 13

What are the causes of secondary intracerebral haemorrhage?

Answer 13

Vascular abnormality (AVM, aneurysm, cavernoma, venous angioma), tumour, impaired coagulation, vasculitis, iatrogenic,

Question 14

How do haemorrhagic strokes appear on CT?

Answer 14

Bright, this eventually subsides as the blood is broken down to Hb

Question 15

What is the immediate management of ischaemic stroke which must be started within 4.5 hours?

Answer 15

thrombolysis, IV alteplase

Question 16

What is the anticoagulation management of individuals with ischaemic stroke?

Answer 16

300mg aspirin daily 2/52
Lifelong anticoagulation (clopidogrel)

Question 17

What is the immediate management of a Pt presenting with haemorrhagic stroke?

Answer 17

IV prothrombin complex concentrate and vitamin K. Get control of hypertension

Question 18

What is the primary prevention of strokes?

Answer 18

Control and magament of HTN, DM, hypercholesterolaemia, CVD, smoking

Question 19

What the difference in vascular origin between a TACS, PACS, POCS, and LACS?

Answer 19

TACS- total anterior circulation syndrome usually is means a proximal middle cerebral artery or ICA occlusion.
PACS- partial anterior circulation syndrome means a branch of the MCA occlusion
POCS- posterior circulation syndrome means an occlusion of vertebral, basilar, cerebellar or PCA vessels
LACS- Lacunar syndrome means small penetrating artery occlusion, usually in lenticulostriate branches of MCA, or supply to brainstem or deep white matter

Question 20

What is the difference in how TACS, PACS, POCS and LACS present?

Answer 20

TACS- hemiparesis AND higher cortical dysfunction AND homonymous hemianopia
PACS- isolate higher cortical dysfunction OR any two of hemiparesis, higher cortical dysfunction, hemianopia
POCS- Isolate hemianopia or cerebellar syndromes
LACS- pure motor OR pure sensory OR sensorimotor OR ataxic hemiparesis OR clumsy hand dysarthria