cerebral infarction (clinical)

Question 1

what is a stroke defined as?

Answer 1

sudden onset of focal or global neurological symptoms caused by ischaemia or haemorrhage and lasting more than 24 hours

Question 2

what percentage of strokes are ischaemic?

Answer 2

about 85%

Question 3

what differentiates a transient ischaemic attack from a stroke?

Answer 3

symptoms resolve within 24 hours

most TIAs resolve within 1-60mins

Question 4

what is the most common cause of ischaemic stroke?

Answer 4

large artery atherosclerosis

Question 5

what is the most common cause of haemorrhagic stroke?

Answer 5

primary intracerebral haemorrhage

Question 6

what does prolonged hypoxia lead to?

Answer 6

anoxia

Question 7

what does anoxia lead to?

Answer 7

infarction (complete cell death, which leads to necrosis)

Question 8

what can cause further damage in a stroke patient?

Answer 8

edema depending on the size and location of the stroke

secondary haemorrhage into the stroke

Question 9

what are some non modifiable risk factors for stroke?

Answer 9

previous stroke
being old
being male
having a horrible family history

Question 10

what is the effect of diabetes on the chances of having a stroke?

Answer 10

increases the incidence of stroke up to 3 fold in both sexes

Question 11

what is the effect of smoking on the chances of having a stroke?

Answer 11

2 fold increased risk of cerebral infarction

3 fold risk of sub arachnoid haemorrhage

Question 12

what is the effect of increased serum lipids?

Answer 12

increase stroke risk due to blood vessel wall atheroma

Question 13

what does increased plasma level of LDL result in?

Answer 13

excessive amounts of LDL within the arterial wall

Question 14

what is the effect of alcohol on stroke risk?

Answer 14

small amounts of alcohol decrease stroke risk

heavy drinking increases the chances of having a stroke 2.5 times

Question 15

what comprises the anterior arterial supply to the brain

Answer 15

2 anterior cerebral arteries

2 middle cerebral arteries

Question 16

what comprises the posterior arterial supply to the brain?

Answer 16

2 vertebral arteries
3 pairs of cerebellar arteries
2 posterior cerebral arteries

Question 17

where are borderzone anastomoses located?

Answer 17

between the peripheral branches of the anterior, middle and posterior cerebral arteries

Question 18

what are some symptoms of anterior cerebral artery occlusion?

Answer 18

contra lateral-
paralysis of the foot and leg
sensory loss over foot and leg
impairment of gait and stance

Question 19

what are some symptoms of middle cerebral artery occlusion?

Answer 19

contra lateral:
paralysis of face/arm/leg
sensory loss face/arm/leg
homonymous hemianopia
gaze paralysis to opposite side
aphasia if stroke is on the dominant side
unilateral neglect and agnosia for half of the external space if non dominant stroke

Question 20

what are some symptoms of right hemisphere damage?

Answer 20

left hemiplegia
homonymous hemaniopia
agnosias (neglect syndromes)

Question 21

what are 4 types of agnosias?

Answer 21

visual agnosia
sensory agnosia
anosagnosia (denial of hemiplegia)
prosopagnosia (failure to recognise faces)

Question 22

what structures are involved in a stroke affecting the posterior circulation of the brain?

Answer 22

brainstem
cerebellum
thalamus
occiptal and medial temporal lobes

Question 23

what should acute ischaemic stroke therapies aim to do?

Answer 23

restore blood supply
prevent extension of ischaemic damage
protect vulnerable brain tissue

Question 24

what is the criteria for tissue plasminogen activator use

Answer 24

less than 4.5 hours from symptom onset
disabling neurological deficit
symptoms present for more than 60 minutes
consent obtained

Question 25

what is the exclusion criteria for IV TPA?

Answer 25

anything that increases the possibility of haemorrhage
BP > 185 systolic or ?110 diastolic
glucose <2.8 or ?22mmol/L

Question 26

what can increase the possibility of haemorrhage?

Answer 26

blood on CT scan
recent surgery
recent episodes of bleeding
coagulation problems

Question 27

what is an effective treatment for symptomatic internal carotid artery stenosis?

Answer 27

carotid endarterectomy

Question 28

what investigations are appropriate for stroke?

Answer 28

routine blood tests
CT or MRI head
ECG
echo
carotid doppler
cerebral angiogram
hyper coagulable blood screen

Question 29

what are some common secondary prevention medications for stroke?

Answer 29

anti hypertensives
anti platelets
lipid lowering agents
warfarin for AF
carotid endarterectomy