Stroke + Differentials Flashcards
What % of strokes are ischaemic and what % are haemorrhagic?
85% ischaemic
15% haemorrhagic
What anatomical factors cause intracerebral haemorrhage?
1) Small vessel disease
2) Amyloid angiopathy
3) AVMs
What haemodynamic factor causes intracerebral haemorrhage?
Hypertension
What haemostatic factors cause intracerebral haemorrhage?
1) Anticoagulants
2) Anti-platelets
3) Thrombolytics
What other factors cause intracerebral haemorrhage?
1) Recreational drugs
2) Vasculitis
Describe amyloid angiopathy related haemorrhage
- Amyloid deposition in cortical artery muscle layers
- Typically causes local intracerebral haemorrhage or ICH at grey/white matter border
- Prone to recurrence
What are 8 causes of ischaemic stroke?
1) Intracranial atherosclerosis
2) Penetrating artery disease
3) Carotid plaque with arteriogenic emboli
4) Flow reducing carotid stenosis
5) Cardiogenic emboli
6) AF
7) Valve disease
8) Left ventricular thrombi
What are 4 major risk factors for ischaemic stroke?
1) Hypertension
2) Smoking
3) Diabetes
4) Hyperlipidaemia
What does a stroke examination consist of?
1) GCS
2) Temperature
3) Pulse (fibrillation)
4) BP
5) Heart sounds → murmurs, septal defects
6) Carotid bruits
7) Evidence of aspiration
8) Neurological deficit → visual, speech, facial, motor, sensory
What investigations do you need to do on someone with a stroke?
1) ECG
2) Blood tests → haemoglobin, platelets, clotting, biochemistry
In what timeframe do all patients need a brain scan?
< 1hr
Which patients need a brain scan urgently?
1) Unconscious
2) Deteriorating conscious level
3) On anticoagulants
4) Presentation within thrombolysis window of opportunity
What area is a key collateral circulation?
Circle of Willis
What are the 3 vascular territories of the cerebral hemisphere?
Anterior, middle and posterior cerebral
What are the signs of a lesion in the ACA?
1) Contralateral hemiparesis → leg more than arm/face
2) Cortical signs → emotional changes, dysphagia (left ACA)
What are the signs of a lesion in the MCA?
1) Contralateral hemiparesis → arm/face more than leg
2) Contralateral hemisensory loss
3) Cortical signs → contralateral heminopia, contralateral hemineglect, dysphagia (left MCA)
What are the signs of a lesion in the posterior cerebral artery?
1) Contralateral heminopia
2) Contralateral hemineglect
What are the signs of a lesion in the vertebrobasilar territory?
1) Nausea and vomiting
2) Diplopia
3) Vertigo and nystagmus (involuntary eye movement)
4) Ataxia
5) Hemi/quadriplegia
6) Visual field defect
7) Coma
What are the signs of a lacunar stroke (small vessel)?
1) Pure hemiparesis
2) Pure hemisensory loss
3) Sensorimotor stroke
4) Ataxic hemiparesis
NO CORTICAL FEATURES
What are the 3 steps to diagnosing the type of stroke?
1) Anatomy → Where is the lesion? Which side? Which territory?
2) Pathology → What is the lesion - infarct or haemorrhage?
3) Aetiology → Why has it occurred? e.g. large artery/small vessel disease, PMG, FH, SH, risk factors
What is a TIA?
An acute loss of focal cerebral or monocular function
How long do symptoms of a TIA last?
< 24h
Why do TIAs occur?
- Inadequate cerebral/ocular blood supply
- Result of arterial thrombosis or embolism → artery, cardiac or haematological disease
What does TIA stand for?
Transient ischaemic attack
How do you diagnose a TIA?
- Clinical diagnosis without a specific diagnostic test
- Rely on a constellation of clinical features
What are non-focal neurological symptoms?
Symptoms which do not suggest a TIA unless accompanied by focal neurological symptoms
What are examples of non-focal neurological symptoms
1) Faintness
2) Non-specific dizziness
3) Light-headedness
4) Confusion
5) Mental disorientation
6) Incontinence
7) Drop attacks
8) Syncope
What are 6 causes of transient focal neurological attacks?
1) TIA (focal cerebral ischaemia)
2) Migraine with aura (with or without headache)
3) Partial (focal) epilepsy
4) Transient global amnesia (TGA)
5) Multiple sclerosis
6) Labyrinthine disturbances → Meniere’s disease, BPPV, benign recurrent vertigo, labyrinthitis/vestibular necrosis
What 5 conditions starting with S does stroke mimic?
1) Syncope
2) Seizures
3) Sepsis
4) Space occupying lesion (tumour)
5) Somatisation
In what kind of patients does migraine with aura tend to occur?
Younger patients (than stroke) with a family history
What is migraine with aura?
A positive phenomena, usually < 60 mins that doesn’t leave any residual deficit
- Progression from one symptom to another without delay e.g. visual symptoms to parasthaesiae to dysphagia
Describe the visual symptoms of migraine with aura
- Can be homonymous, unilateral or central
- Flashes of light, zig-zag lines, scintillations, fortification spectra which usually build up or expand
Describe the sensation symptoms of migraine with aura
- Parasthaesiae or heaviness in one or other limbs
- Evolves/spreads within several minutes in marching pattern hand to elbow then face into tongue
What is epilepsy?
A focal, sudden positive sensory or motor phenomena
What are the symptoms of epilepsy?
- Multiple attack of pins and needles on one side of limbs
- Sensation will start somewhere and then spread v quickly to adjacent body parts over seconds/1 min
- Focal jerking
- Altered awareness
How is epilepsy different from TIA or migraine time wise?
- Epilepsy spreads over seconds
- Migraine over minutes
- TIA tingling arises in all affected body parts at the same time
What is transient global amnesia (TGA)?
A sudden disorder of memory in middle-aged or elderly patients
What happens in TGA?
- For a period (some hours), patient cannot memorise any current/new information (anterograde amnesia)
- They often also can’t recall events of the past few days/weeks (retrograde)
- After a few hours, they return back to normal without any neurological signs
- Might be asking same questions repeatedly, although orientated
How might someone with a glioma with vasogenic oedema present?
- Week history of sudden onset weakness in left hand which lasted several minutes (suspect TIA but no vascular risk factors)
- Motor and sensory examination normal (but patient says hand doesn’t feel right)
- History of profound weight loss for 6 months with occasional headaches for the last month
How do you work out if neurological symptoms are due to vascular pathology (cerebral ischaemia/haemorrhage)?
1) If they are focal rather than non-focal
2) If the focal symptoms are negative rather than positive
3) Sudden onset
4) Maximal at onset rather than progressing over a period
IF YES to all questions, then likely to be vascular
What is the relative risk reduction of aspirin, statins and BP lowering in most patients?
Aspirin = 20%
Statin = 20%
BP lowering = 30%
What treatment will be given to a patient who had a TIA who has right internal carotid artery stenosis?
Carotid endarterectomy (removal of plaque) 2 days after presentation
What are the 5 treatments for stroke?
1) Stroke units
2) Intravenous thrombolysis
3) Intra-arterial interventions
4) Surgery for haemorrhagic stroke
5) Preventing complications
Why is it important to open up the blocked artery as soon as possible?
Time is brain → to reduce irreversible brain damage and dead infarcted tissue
What is an example of an intra-arterial intervention?
Endovascular thrombectomy → removing clot from artery
What can be used to treat severe stroke?
Hemicraniectomy → half of scalp removed, relieves pressure (can recover relatively well)
Describe the patient who might need a hemicraniectomy
- Aphasic (can’t speak or follow commands)
- Gaze paresis (eyes deviate to left)
- Right sided heminopia, neglect, hypotonia, weakness, sensory deficit, extensor plantar response
- Normal left sided neurology
- Right handed?
What is used to prevent complications/stroke?
MRI imaging of proximal DVT and PE
What treatment can be used to reduce risk of DVT in patients who have had a stroke?
Intermittent pneumatic compression
What is hemiplegia?
Paralysis of one side of the body
What may some ischaemic strokes be preceded by that act as warning signs?
TIAs
What is a stroke?
- Irreversible brain damage caused by a sudden interruption to the vascular supply leading to cerebral ischaemia
- Brain cells no longer receive oxygen, become hypoxic, swell and die
What are the two types of causes of stroke?
Embolic/thrombotic
What are embolic clots?
Blood clots that form elsewhere, travel and lodge in end vessels
What are thrombotic clots?
Blood clots that form locally, usually at an area where the wall is affected by atherosclerosis → these clots gradually increase and eventually block the vessel
