Cerebral Infarction Flashcards
what % of stroke patients will die within a year?
1/3rd
what type of stroke is more common?
- ischaemic
- haemorrhagic
- ischaemic (85%)
what is the definition of a stroke?
the sudden onset of focal or global neurological symptoms caused by disruption of blood supply (ischemia or hemorrhage) and lasting more than 24 hours.
what are the main causes of ischaemic strokes?
atherosclerosis
cardioembolism
small artery occlusion
cryptogenic
what is the most common cause of a haemorrhagic stroke?
primary intracerebral haemorrhage
what percentage of strokes are haemorrhagic ?
15%
is the incidence of the different types of strokes the same over the world?
no
- in asia there is a slightly higher number of haemorrhagic strokes
what are the advantages of CT scans?
cheap
fast
can show bone very well
what are the pros and cons of MRI scans?
pros
- show more detail
- can show soft tissue very well
- very good for ischaemic strokes
- uses no radiation
cons
- takes longer
why is it good to do scans when the diagnosis is unclear?
good to get a diagnosis and to plan the treatment of the patient
how many deaths are there in the UK per year due to stroke?
67,000
state the cascade of ischaemia
- failure of cerebral blood flow
- interruption of blood supply
- can result in hypoxia
- prolonged hypoxia and result in anoxia
- anoxia results in infarction and necrosis
- further damage from oedema
what is ischaemic penumbra ?
the area of damage around the ischaemic core
what are the non modifiable risk factors of stroke?
- age
- male
- family history
- previous stroke
- genetics
what are the modifiable risk factors of stroke?
hypertension smoking cholesterol diet alcohol high BMI diabetes cardiac problems
what does high lipid levels increase the risk of?
Atheroma
what artery supplies the face, mouth and hand of the homunculus ?
middle cerebral artery
what artery supplies the arm, trunk and legs of the homunculus ?
anterior cerebral artery
what artery supplies the brocas area?
middle cerebral artery
what are the symptoms of a MCA occlusion ?
contra-lateral
- paralysis of face,arm,leg
- sensory loss
- homonymous hemianopia
- aphasia if dominant side is affected (left)
what main areas of the brain are affected with a MCA occlusion ?
brocas area
wernickes area
auditory area
sensory and motor areas
with a MCA occlusion which direct do the eyes gaze?
gaze towards the damaged side of the brain
and away from the paralysis
what is visual agnosia ?
when you can see one side of the lecture hall and not the other
what is sensory agnosia ?
when you can only feel one finger when the doctor was touching both sides of your body