Stroke and Neurodegeneration (Dr TD Farr) Flashcards
What is stroke?
The acute onset of neurological defecits (lasting for more that 24h) due to disturbance in blood supply to the brain
What are the neurological symptoms associated with stroke?
Aphasia - speech problem
Dysphasia - swallowing
Apraxia - control of speech
Hemiparesis - half-body paralysis
Facial weakness
Confusion, dizziness and vision impairments
Thunderclap headache (associated with hemorrhage)
24h symptoms (if less - TIA) TIAs are often a sign that precedes a major stroke afterwards
What are some non-modifiable stroke risk factors?
Age, race, genetics, gender (menopause - estrogen has a neuroprotective function so it is less likely in women before menopause then equally risky post menopause.)
What are some of the modifiable risks associated with stroke?
Hypertension, smoking, diabetes, high cholesterol, obesity, activity levels.
What are the two main types of stroke?
Ischaemic or Hemorrhagic
What is the difference between an ischaemic stroke compared to a hemorrhagic stroke?
An ischemic stroke happens when a blood vessel (artery) supplying blood to an area of the brain becomes blocked by a blood clot. About 80 out of 100 strokes are ischemic strokes. A hemorrhagic stroke happens when an artery in the brain leaks or bursts (ruptures).
What are the two types of hemorrhagic stroke?
Intracerebral and subarachnoid (subarachnoid, blood gets into the meninges and causes pressure)
What are the two types of ischemic stroke?
Thrombotic and embolic
Thrombotic strokes are caused by a blood clot that develops in the blood vessels inside the brain. Embolic strokesare caused by a blood clot or plaque debris that develops elsewhere in the body and then travels to 1 of the blood vessels in the brain via the bloodstream.
What does FAST stand for?
Facial weakness
Arm weakness
Speech difficulty
Time to call 999
What are the two main types of artery that supply the brain?
Carotid arteries (forebrain) Vertebral arteries (hindbrain)
What is The Circle of Willis?
A major anastomosis for the brain
It is an arterial circle at the base of the brain and it can compensate for/minimise collateral damage when things go wrong in the circulation of the brain.
What are the four main pairs of cerebral arteries?
Basilar artery (brain stem) and posterior cerebral arteries (medical occipital and inferior temporal lobe, hippocampus)
Anterior cerebral artery (medial frontal and superior parietal lobe, corpus callosum)
Middle cerebral arteries (lateral temporal and parietal lobes and posterior frontal lobe) and Lenticulostriate arteries (internal capsule and basal ganglia).
What is an aneurism?
The most common cause of a hemorrhage is rupture of a saccular (berry) aneurism.
An excessive localised swelling of the wall of an artery
What is aneurism coiling?
Clipping prevents blood going into the aneurism.
Coiling also stops the bursting of an aneurism.
Insert a microcanula and feed coil into aneurism
What tests are used to diagnose a stroke?
ROSTIER; RecOgnition of Stroke In the Emergency Room (higher score = more serious) ABCD (Age, Blood pressure, Clinical features, Duration, Diabetes) CT Scan (Computed tomography)
Are CT scans effective in detecting strokes?
CT is 40-60% successful in detecting acute ischaemic stroke; it is often not clear in CT scan results
What are Hounsfield Units (HU)?
In the CT scan it shows the progression of basal ganglia deterioration
Density of color
What is a better scan method for diagnosing an acute ischaemic stroke?
MRI
Diffusion weighted imaging
What is the most common cause of hemorrhage?
Aneurism
Typically located near junction vessels
Anterior, middle, internal, basilar
What are the three diagnosis tests that are used to diagnose each typeof stroke?
ROSTIER (acute classification)
ABCD (transient ischemic attack)
Hunt and Hass haemorrhage
What are CT scans used for?
CT is used to rule out hemorrhage
How can ischemic tissue become clear on a CT scan?
Becomes more dense over time / darker
What is ‘The Penumbra’?
‘the partially shaded outer region of the shadow cast by an opaque object’
It represents potentially salvageable tissue
In ischemia it is the hallmark of a stroke and is why time is brain in a patient suffering a stroke.
If a stoke is not treated quickly then the penumbra is small.
What is the only treatment for ischemic stroke?
Recombinant tissue plasminogen activator (rt-PA) (Alteplase) is the only treatment.
The window for Alteplase is 3h from symptom onset. (Thought to break up fibrogen in clot)?
What is the pathophysiological overview of stroke?
DIAGRAM including excitatory pathway and inflammation
