4 - Stroke Syndromes Flashcards
What are the questions that need you need to ask yourself when a patient is having a stroke?
- Is it a stroke and what syndrome is it?
- What is the aetiology?
- Are there any complications?
- What treatment does this patient need and when?
- How well is this patient likely to do?
- When can they leave our care?
What is a stroke and the two main categories of this?
Sudden onset focal neurological deficit of vascular aetiology, with symptoms lasting >24 hours (or with evidence of infarction on imaging)
Ischaemic (85%) or Haemorraghic (15%)
Due to abnormal cerebral perfusion
How are Haemorraghic and Ischaemic strokes further divided?
Ischaemic: Bamford/Oxford classification
Haemorraghic (bleeding into parenchyma, ventricles or subarachnoid space): ICH or SAH
What are the causes of ischaemic and haemorraghic strokes?
Ischaemic: Thrombosis, Emboli (AF!), Dissection
Haemorraghic: HTN, brain tumour, vasculitis, bleeding disorders, trauma
What are some risk factors for a stroke?
Strong risks: male, FHx hypertension, smoking, diabetes, AF
Weak risks: hypercholesterolaemia, obesity, poor diet, oestrogen-containing therapy, and migraine.
What is the Circle of Willis made up of and what lobes of the brain do the 3 main cerebral arteries supply?
(Draw image of Circle of Willis)
Anterior Circulation: ICA
Posterior Circulation: Vertebrobasillar system
ACA: medial frontal and parietal lobes
MCA: lateral surface of each brain hemisphere including the internal capsule and basal ganglia
PCA: occipital lobe and inferior temporal lobe as well as some deep structures (e.g. thalamus)
What is the blood supply to cerebellum?
What are the three most common causes of ischaemic stroke?
- Large artery atherosclerosis (emboli)
- Small artery atherosclerosis (thrombus)
- Cardioembolic (AF)
Rare: vasculitis, dissection
What is a TACS stroke?
Ischaemic Total Anterior Circulation Stroke (3/3)
- Contralateral hemiplegia or hemiparesis, AND
- Contralateral homonymous hemianopia, AND
- Higher cerebral dysfunction (e.g. aphasia, neglect)
Involves MCA or ACA
What is a PACS stroke?
Ischaemic Partial Anterior Circulation Stroke (⅔)
ACA or MCA
What is a LACS/Lacunar stroke and what vessel is affected?
Should be no visual defects, no higher cerebral dysfunction and no brainstem dysfunction
Affects deep perforating arteries, usually supplying internal capsule
What is a POCS stroke and what vessel is affected?
Ischaemic posterior circulation syndrome
Involves vertebrobasilar arteries and associated branches (supplying the cerebellum, brainstem, and occipital lobe)
- Cerebellar dysfunction, OR
- Conjugate eye movement disorder, OR
- Bilateral motor/sensory deficit, OR
- Ipsilateral cranial nerve palsy with contralateral motor/sensory deficit, OR
- Cortical blidness/isolated hemianopia.
How may someone with a haemorraghic stroke present?
- Headache
- Altered mental status
- Nausea & Vomiting
- Hypertension
- Seizures
- Focal neurological deficits (dependent on location of bleed)
How may someone with an anterior ischaemic stroke present?
Depends on location of infarct
- Unilateral weakness and/or sensory deficit: face and/or arms and/or legs
- Homonymous hemianopia: visual field loss on the same side of both eyes
- Higher cerebral dysfunction: dysphasia, visuospatial dysfunction (e.g. neglect, agnosia)
How may someone with a posterior ischaemic stroke present?
Affects brainstem, cerebellum and occipital lobe so balance/visual/cranial nerve issues:
- Dizziness
- Diplopia
- Dysarthria & Dysphagia - difficult to speak and swallow
- Ataxia
- Visual Field defects
- Brainstem syndromes: often seen with crossed signs (*ipsilateral cranial nerve lesions with contralateral sensory and motor limb deficits)
What are posterior stroke syndromes and some examples of these?
Syndromes that occur due to infarction of specific posterior circulation arteries
- Wallenburg syndrome
- Locked-in syndrome
- Weber’s syndrome
- Lateral pontine syndrome
What is Wallenburg syndrome and what vessel is affected?
- Posterior inferior cerebellar artery occlusion
- Lateral medullary syndrome
- Symptoms: ipsilateral Horner’s syndrome, ipsilateral loss of pain and temperature sensation on the face, and contralateral loss of pain and temperature sensation over the contralateral body, nystagmus, vertigo, diplopia
What is Locked In syndrome and what vessel is affected?
- Basillar artery occlusion
- Quadriparesis with preserved consciousness and ocular movements
Often this type of occlusion leads to sudden death or LOC
What is the difference between ischaemia and infarction?
Ischaemia is reversible, Infarction is irreversible
Ischaemia is insufficient blood flow to meet metabolic demands. Infarct is death of tissue to poor oxygen supply
How do you ‘age’ and infarct?
What is the gold standard imaging in stroke and why?
Non-Contrast CT
Highly sensitive for haemorrhage so can rule this out to see if can do thrombolysis
Also can pick up stroke mimics e.g tumour, AV malformation
What might you see on a non-contrast CT with a hyper acute ischaemic stroke?
(NB)
- Nothing
- Hyperattentuating area in vascular territory (hypoattentuating if old infarct) - draker areas
- Sulcal effacement - it has been displaced./ the sulci area has been toaken over by the blood
- Loss of grey-white matter differentiation
When are perfusion CT scans good in acute stroke?
Can show the difference between dead brain (infarct) and salvageable brain
Larger core infarct, more risk of haemorrhage with thrombolysis
What is the pathophysiology of a haemorraghic stroke?
Weakening of cerebral vessels leading to cerebral vessel rupture and haematoma formation.
Clinical deficit is caused directly by neuronal injury and indirectly by cerebral oedema (this peaks at day 5 following symptom onset)
SAH and ICH
How can haemorraghic stroke lead to death?
Early: cerebral herniation
Late: complications
How can you tell the difference between a hypertensive stroke and a cerebral amyloid antipathy stroke?
Hypertensive usually in basal ganglia and just happen once
What are some complications of an ICH?
How are MRIs used differently to CTs in a stroke?
What is capsular warning syndrome?
Recurrent stereotyped lacunar TIAs (LACS symptoms) that occur over minutes and fluctuate
High risk of completed stroke
When there is reduced flow in MCA leads to hypo perfusion of end lenticulostriate arteries
How may intracranial stenosis present?
Focal symptoms coincide with other evidence of hypo perfusion e.g dizziness, pallor, clamminess
CT angiography
What is the TOAST criteria?
Five subtypes of ischemic stroke
What are some causes of stroke mimics?
(NB - Image recall)
Group 1 - Readily recognised on brain imaging (MRI)
- SOL
- MS
- Subdural haematoma
Group 2 - Distinct non-stroke features but referred due to being lay or non-specialists
- BPPV
- Vestibular neuronitis
- Bell’s Palsy
- Transient global amnesia
Group 3 - Clinically different to stroke but features subtle so need brain imaging
- Complicated migraine with aura
- Focal seizures
What are the features of transient global amnesia?
- Dysfunction of “episodic” memory
- Preservation of other kinds of memory e.g. procedural memory (hence patients are able to make a cup of tea or drive during episode), biographical memory
- during tnis episode the perosn cant make new memories, in this moment you cant rememember where you are or how you got there
How can you assess the prognosis of stroke?
- NIHSS score
- OCSP class
- Recovery trajectory and Functional plateau
How can you tell the difference between a hypertensive stroke and a cerebral amyloid antipathy stroke?
Hypertensive usually in basal ganglia and just happen once
What is a TACS stroke?
Ischaemic Total Anterior Circulation Stroke (3/3)
- Contralateral hemiplegia or hemiparesis, AND
- Contralateral homonymous hemianopia, AND
- Higher cerebral dysfunction (e.g. aphasia, neglect)
Involves MCA or ACA
