Stroke

Question 1

What makes up the anterior circulation of the brain?

Answer 1

ACA, MCA, posterior communicating artery

Question 2

What makes up the posterior circulation?

Answer 2

PCA + joins anterior via posterior communicating

Question 3

What does the ACA supply?

Answer 3

frontal and parietal lobe

Question 4

What does the MCA supply?

Answer 4

lateral brain hemisphere including internal capsule and basal ganglia, most common site of infarction

• internal capsule - large number of motor and sensory fibres travel to and from the cortex
• basal ganglia - motor control, learning, executive functions

Question 5

What does the PCA supply?

Answer 5

• occipital lobe and inferior proportion of temporal lobe, and thalamus
  • thalamus - relay motor, sensory signals to cerebral cortex, regulate sleep, alertness etc

Question 6

What is a stroke?

Answer 6

serious life-threatening medical condition that happens when the blood supply to part of the brain is cut off
- ischaemia: thrombosis, embolism
- haemorrhage

Question 7

What is a TACS?

Answer 7

total anterior circulation stroke
- unilateral weakness +/- sensory deficit within face, arm or leg, homonymous hemianopia, higher cerebral dysfunction

*ACA or MCA

Question 8

What is PACS?

Answer 8

partial anterior circulation stroke
- 2/3 of unilateral weakness +/- sensory deficit within face, arm or leg, homonymous hemianopia, higher cerebral dysfunction

*ACA or MCA

Question 9

What is a lacunar stroke?

Answer 9

• deep perforating arteries like lenticulostriate , which supply thalamus, basal ganglia or pons
• pure motor hemiparesis, pure sensory, ataxic hemiparesis, dysarthria-clumsy hand syndrome, sensorimotor

Question 10

What is POCS?

Answer 10

posterior circulation stroke
- vertebrobasilar arteries
- brain stem or cerebellar syndrome, loss of consciousness, isolated homonymous hemianopias

Question 11

What are the symptoms of Webers syndrome?
(branches of the posterior cerebral artery that supply the midbrain)

Answer 11

Ipsilateral CN III palsy
Contralateral weakness of upper and lower extremity

Question 12

Posterior inferior cerebellar artery (lateral medullary syndrome, Wallenberg syndrome)?

Answer 12

ipsilateral Horner’s syndrome, ipsilateral loss of pain and temperature sensation on the face
contralateral loss of pain and temperature sensation over the contralateral body

Question 13

What are the symptoms of Anterior inferior cerebellar artery (lateral pontine syndrome)?

Answer 13

Symptoms are similar to Wallenberg’s (see above), but:
Ipsilateral: facial paralysis and deafness

Question 14

What are some risk factors for haemorrhagic stroke?

Answer 14

age
hypertension
arteriovenous malformation
anticoagulation therapy

Question 15

What are some risk factors for ischaemic strokes?

Answer 15

General risk factors for cardiovascular disease
age
hypertension
smoking
hyperlipidaemia
diabetes mellitus

Risk factors for cardioembolism
atrial fibrillation

Question 16

How might a stroke present?

Answer 16

• sudden onset of neurological symptoms - vascular cause
  
  • asymmetrical
• common
  
  • limb weakness
  • facial weakness
  • dysphasia (speech disturbance)
  • visual field defects
  • sensory loss
  • ataxia and vertigo (posterior circulation infarction)

Question 17

How might you differentiate haemorrhagic from ischaemic stroke?

Answer 17

unable to tell without CT head!

Question 18

How might you assess a stroke?

Answer 18

Face - ‘Has their face fallen on one side? Can they smile?’
Arms - ‘Can they raise both arms and keep them there?’
Speech - ‘Is their speech slurred?’
Time - ‘Time to call 999 if you see any single one of these signs.’

Question 19

What scoring system might you use in hospital?

Answer 19

National institutes of health stroke scales
*for clinical outcome

Question 20

What differentials might you consider in stroke patients?

Answer 20

• Toxic/ metabolic - hypoglycaemia, drug, alcohol consumption
• neuro - seizure, migraine, Bell’s palsy
• space occupying lesion - tumour, haematoma
• infection - meningitis/ encephalitis, systemic infection with decompensation of old stroke
• syncope - extremely uncommon presentation of TIA
• non-organic - functional neuro disorders

Question 21

What major investigations might you consider in stroke patients?

Answer 21

CT head - ischaemic or haemorrhagic
*if normal treat as ischaemic as may not show initially

bedside, bloods, imaging
special - echo, carotid doppler, 24h tape, young stroke screen

Question 22

What is the management for haemorrhagic stroke?

Answer 22

• Anticoagulants (e.g. warfarin) and antithrombotic medications (e.g. clopidogrel) should be stopped to minimise further bleeding + reverse anticoag
• BP control
• larger
  
  • decompressive hemicraniectomy
  • suboccipital craniotomy for posterior fossa bleeds

Question 23

What is the management for ischaemic stroke?

Answer 23

thrombolysis - synthetic tissue plasminogen activator (alteplase)
WITHIN 4.5h

mechanical thrombectomy

Question 24

What are the contraindications for thrombolysis?

Answer 24

previous intracranial haem, seizure at onset of stroke, intracranial neoplasm, suspected SAH, 3m previous stroke or traumatic brain injury, 3w preceding GI haem, pregnancy, oesophageal varices, uncontrolled HTN >200/120

Question 25

What is the indication for thrombectomy?

Answer 25

• removal of thrombus from vessel
• offer within 6h of symptom onset with IV thrombolysis (4.5h window)
• offer to those known to be well between 6-24h previously (wake-up strokes)
• location specific and dependent on potential to salvage brain tissue according to CT

Question 26

What other management considerations should you make?

Answer 26

• blood glucose, hydration, oxygen saturation and temperature - within normal limits
• blood pressure should not be lowered in the acute phase unless “hypertensive encephalopathy”
• aspirin 300mg orally or rectally if haemorrhagic excluded
• AF - anticoag not until haemorrhage excluded and not until 14 days passed from onset of ischaemic stroke
• cholesterol >3.5 mmol/l commenced on a statin, after 48h due to haemorrhagic transformation risk