Cerebral infarction (clinical) Flashcards
Define stroke
The sudden onset of focal or global neurological symptoms caused by ischaemia or haemorrhage and lasting >24 hours
Are most strokes ischaemic or haemorrhagic?
ischaemic
Define transient ischaemic attack
Symptoms resolve within 24 hours and usually within 1-60mins
Some causes of ischaemic stroke
large artery atherosclerosis small artery occlusion - lacunar cardioembolic eg AF undetermined/cryptogenic rare eg arterial dissection
Haemorrhagic stroke causes
primary intracerebral haemorrhage
secondary eg subarachnoid haemorrhage or arteriovenous malformation
Is MRI or CT preferred in stroke?
CT
Ischaemia
Failure of cerebral blood flow to part of the brain caused by interruption of blood supply to brain
Why is hypoxia clinically important in stroke?
stresses cell metabolism
can lead to anoxia and infarction/necrosis
penumbra
What is the penumbra?
Area surrounding ischaemic event
What can further damage in a stroke result from?
oedema
secondary haemorrhage into stroke
Modifiable risk factors of stroke
hypertension
smoking
diet/alcohol/lifestyle
diabetes
Non modifiable risk factors of stroke
male
age
family history
previous stroke
What can chronic hypertension cause in relation to stroke?
worsens atheroma
affects small distal arteries
Small artery lipohyalinosis - what is it?
build up of vessel wall - aneurysm and microclots
Some other risk factors for stroke
OCP/HRT - oestrogen
impaired cardiac function
malignancy
genetic
Anterior circulation to brain
2 ICA –> 2 ACA and 2 MCA
Posterior circulation to brain
2 vertebral –> 1 basilar
3 pairs of cerebellar arteries
2 PCA
2 connections of arterial blood supply in the brain
circle of willis - anterior and posterior communicating arteries
borderzone anastomoses - between peripheral branches of cerebral arteries
symptoms of ACA occlusion (contralateral - 3)
paralysis of foot and leg
sensory loss over foot and leg
impairment of gait and stance
Symptoms of MCA occlusion (contralateral and others)
contralateral - paralysis of face, arm, leg
sensory loss of face, arm, leg
homonymous hemianopia
gaze paralysis to opposite side
aphasia if stroke on left side
unilateral neglect and agnosia if on right side
Agnosia
Inability to process sensory information
3 signs left hemisphere is affected
hemiplegia
homonymous hemianopia
dysphasia
3 signs right hemisphere is affected
left hemiplegia
left homonymous hemianopia
agnosia
4 agnosias if right side of brain affected
visual
sensory
anosagnosia
prosopagnosia
anosagnosia
denying of hemiplegia
prosopagnosia
failure to recognise faces
What are lacunar strokes devoid of?
cortical signs eg dysphasia, hemianopia
Anatomy within posterior circulation of brain
brainstem, cerebellum, thalamus
occipital and medial temporal lobes
List some symptoms of brainstem dysfunction
coma, vertigo, nausea, vomiting, ataxia, cranial nerve palsy, hemiparesis, visual field defects
3 aims of acute ischaemic stroke therapies
restore blood supply
prevent extension of ischaemic damage
protect vulnerable brain tissue
List some potential treatments used in stroke
aspirin, heparin, tPA, thrombectomy, neuroprotectant
List some of the staff in stroke units
OT, SLT, physiotherapist, stroke nurses, dietician, psychologist, orthopist, clinical staff
Orthopist?
For double vision
4 types of stroke
TACS
PACS
LACS
POCS
Which is the most devastating stroke?
TACS
What are the MUSTS when using TPA
consent
symptoms present more than 60 mins but less than 4.5 hours
disabling neurological deficit
Contraindications for TPA use
blood on CT coagulation problems recurrent bleeding recent surgery high bp glucose too high or low
Investigations of stroke
blood - FBC, ESR, glucose, lipids CT/MRI ECG Echo carotid Doppler ultrasound cerebral angiogram/venogram hypercoagulable blood screen
Mural thrombus
thrombus formed in heart chamber
atrial myxoma
non cancerous tumour in heart
Giant cell arteritis - investigation
tender over temporalis
ESR, temporal artery biopsy
secondary prevention of stroke
anti-hypertensives lipid lowering agents anti-platelets warfarin carotid endartectomy
Some other conditions that look like stroke but aren’t
bells palsy
migraine
hypoglycaemia
Management and aims of care
rehab and reintegration quality of life knowledge and improve psychological status prevent recurrance reduce mortality and disability
