Week 3-stroke Flashcards
What is a transient ischaemic attack?
A transient ischaemic attack is a stroke lasting less than 24 hours.
“Brief episode of neurological dysfunction caused by focal brain or retinal ischaemia with symptoms lasting typically less than 1 hour without evidence of acute infarction”
Does a TIA need treatment?
Yes needs immediate treatment to prevent a full blown stroke.
What investigations would be done by the rapid access neuromuscular clinicians after a suspected TIA?
History
Cardiac imaging
ECG
Blood tests.
Which forms of drug reduce the risk of stroke?
Statins and antiplatelet drugs
What is a TIA referred to before the 24 hours is up?
TIA is a retrospective diagnosis so until the 24 hour mark has passed it is known as an acute cerebrovascular syndrome.
What causes cell death in hemorrhagic stroke?
Not only does hypoxia lead to cell death but the bleeding itself activates an inflammatory cascade leading to cellular damage and death.
What common medical conditions can mimic stroke?
Seizures (can give unilateral weakness)
Presyncope (dizziness and lightheadedness don’t normally coincide with stroke. Vertigo can however be seen in posterior strokes)
Sepsis
Acute confusion (delirium)
Transient global amnesia (period where people can’t remember what happened).
What does ROSIER score stand for?
Recognition of stroke in the emergency room.
Positive points on the ROSIER score?
Asymmetrical face weakness, asymmetrical arm weakness, asymmetrical leg weakness, speech disturbance, visual field defect.
Negative points on the ROSIER score
Loss of consciousness or syncope, seizures.
When is the ROSIER score indicative of a stroke?
When the score is more than 0. If less than zero, unlikely.
What sort of imaging will you initially do on presentation of a patient with suspected stroke?
CT scan initially. Very sensitive for blood acutely and readily accessible.
What colour does blood show up on a CT scan?
White.
When would you use an MRI over a CT scan in stroke patients?
CT scan loses sensitivity for blood after about 1 week. Then you should use MRI.
What would an infarcted area look like on a CT scan?
Darker area.
What symptoms would you expect with a total anterior circulation stroke?
Hemiplegia (paralysis of one side of the body) contralateral to the lesion usually with ipsilateral sensory loss.
Hemianopia contralateral to the lesion
New disturbance of higher cerebral dysfunction (e.g. dysphagia)
What symptoms would you expect with a partial anterior circulation stroke?
any of:
Motor/sensory deficit with hemianopia
Motor/sensory deficit with new higher cerebral dysfunction
New higher cerebral dysfunction with hemianopia
New higher cerebral dysfunction alone
A pure motor/sensory deficit less extensive than would be seen in lacunar stroke.
What symptoms would you expect with a posterior circulation stroke?
Any of- ipsilateral cranial nerve palsy with contralateral motor/sensory deficit
Bilateral motor/sensory deficit
Disorder of conjugate eye movement
Cerebellar dysfunction without ipsilateral long tract sign
Isolated hemianopia or cortical blindness
What is a lacunar infarct?
Infarcts in the small perforating vessels supplying the deep structures of the brain.
Which imaging method is best for a posterior circulation stroke?
Generally MRI because CT doesn’t deal well with all the bony structures.
What sorts of functions does the left side of the brain control?
In most people this is the dominant side. From here you get speech, number skills, written language and reasoning.
What sorts of functions does the right side of the brain control?
Creativity, music, spatial orientation and artistic awareness.
What is the most common cause of stroke?
Atheroemboli (50%)
cardioembolic are just 20%
What is the most common cause of cardioembolic stroke?
What else can cause it?
Atrial fibrillation.
Ventricular thrombus, prosthetic valves, rheumatic fever
