The first things to do is decide TIA or Stroke?. This is simple:
- TIA is a focal neurological deficit which resolves within 24h.
- Stroke is a focal neurological deficit which lasts longer 24h.
If it's a stroke you need to decide on what kind. The presentation depends on which artery/ies and so which area of the brain is affected. There are a few types of stroke that you should know about. Broadly speaking these are:
- Total Anterior Circulation Stroke (TACS)
- Partial Anterior Circulation Stroke (PACS)
- Lacunar Stroke (LACS)
- Posterior Circulation (POCS)
The other less common type of stroke is a brainstem stroke.
The symptoms important in identifying an anterior circulation stroke are:
- Higher dysfunction (aphasia, visuospatial disturbance, decreased consciousness level)
- Homonymous hemianopia
- Hemiparesis (2 of face, arm and leg)
All 3 = TACS. 2/3 = PACS. The symptoms must be on the same side (if not, it's probably not a stroke. Remember: right-sided symptoms = left T/PACS; left-sided symptoms = right T/PACS.
It's actually pretty simple. Visual neglect (ignoring things on one side of vision), visual inattention (inability to see thing on one side of vision) and sensory inattention (inability to determine which side of the body is being touched) are all symptoms indicative of an anterior circulation event.
These events are usually middle cerebral artery infarcts. Anterior cerebral artery infarcts can cause: contralateral leg paralysis, urinary incontinence, grasp reflex, gegenhalten rigidity (rigidity against passive movement, perserveration (uncontrollable repetition of the same word), "alien limb" syndrome (limb takes a "mind of its own" aka Dr Strangelove syndrome - I'm not sure they're not taking the piss. Speaking of which...),
Basically, these cause cerebellar signs so think of your cerebellar examination with the acronym VANISH'D: Vertigo, Ataxia, Nystagmus, Intention tremor, Slurred speech (this occurs in TACS/PACS too), Heel-shin test, Dysdiaodochokinesis. And a broad-based gait which didn't fit.
With lacunar strokes you basically get:
- Pure motor
- Pure sensory
- Ataxic hemiparesis
Essentially these come down to: headache, vertigo, nausea and vomiting; weakness, either bilateral or unilateral; visual disturbance, nystagmus, ptosis or Horner's syndrome; hearing loss; dysarthria; dysphagia; ataxia; impaired level of consciousness; and altered pattern of respiration.
- CT within 24 hours (mainly to rule out a bleed)
- MRI DWI (diffusion-weighted imaging) if the infarct is likely to be small.
- Ultrasound carotid dopplers (stenosis is a risk factor for stroke)
- ECG to look for AF
- FBC (polycythaemia), U+Es (in case contrast required or gentamicin required to treat aspiration pneumonia), LFTs (statin is excreted by the liver), TFTs (hyperthyroidism can cause neurological symptoms), Lipid profile (cholesterol), glucose (rule out hypoglycaemia), ESR & CRP (rule out temporal arteritis)
If within 4-and-a-half hours of witnessed symptom onset (i.e. if you wake up with a stroke, you won't get it), alteplase (thrombolytic agent) maybe given to break down the clot. There are number of contraindications to thrombolysis - if you want them, look 'em up.
Medications: Aspirin (300mg for two weeks, then 75mg for life), statin and dipyridimole.
Lifestyle advice: exercise, stop smoking, lose weight, don't drive for at least one month.
Endarterectomy if carotid dopplers show stenosis (the stenosis is cleaned out by vascular surgeons). Oddly, if it is totally occluded, it no longer needs surgery.