Stroke Flashcards
hoe long must a stroke last to be defined as stroke?
more that 24 hours
give some general symptoms of stroke
> loss of power > loss of sensation > loss of speech > loss of vision > loss of coordination
what is gaze palsy?
double vision horizontally
what causes damage to part of the brain during a stroke?
blockage of blood vessel by a thrombus or embolus, or due to a haemorrhage from a ruptured blood vessel
what does the external carotid artery supply?
the face
what is unique about the basilar artery?
it is formed from two smaller vessels which join together
what does the vertebral-basilar system supply?
the brain stem, cerebellum and occipital lobes with the posterior cerebral artery
what does the internal carotid supply?
the hemispheres and cortical deep white matter
what two arteries does the internal carotid split into?
the anterior cerebral and the middle cerebral
give some causes of stroke
> blockage of vessel with thrombus
disease of vessel wall
disturbance of normal properties of blood
rupture of vessel wall (haemorrhage)
what percentage of strokes at ischaemic?
85%
what causes for ischaemic stroke are there?
> large artery atherosclerosis > cardioembolic > small artery occlusion > arterial dissection (rare) > Venous sinus thrombosis (rare)
what percentage of strokes are haemorrhagic?
15%
what causes for haemorrhagic stroke is there?
> primary intracerebral haemorrhage
> secondary haemorrhage
give two examples of causes of a secondary haemorrhagic stroke
> subarachnoid haemorrhage
> arteriovenous malformation
what is an ischaemic stroke?
a clot stops blood supply to an area of the brain
what is a haemorrhagic stroke?
when blood leaks into brain tissue, there is a pressure effect on the brain
what is the commonest cause of a cardioembolic stroke?
atrial fibrillation
describe a lacunar stroke
the walls of a small vessel in the brain get thickened creating a smaller lumen. this occlusion creates a small area of damage. this is generally caused by hypertension.
describe how a carotid dissection can lead to stroke
it can be idiopathic or due to trauma. the wall of the carotid tears and a clot then thrombus forms on top of that
what can you tell about the stroke from the signs and symptoms of the patient?
> what side of the brain is affected
whether the lesion is in the brainstem (brainstem stroke)
whether the cortex is involved (cortical stroke)
if the lesion is in the white matter (lacunar stroke)
what blood vessel is involved
what is TACS?
total anterior circulation stroke
what is PACS?
partial anterior circulation stroke
what is LACS?
lacunar stroke