Stroke Flashcards
Stroke is development of what two neurologic deficit related to vascular event?
focal or global
2 kinds of atypical strokes?
- transient
2. ‘silent’
Strokes are:
75%
20%
5%
75% Infarction
20% Haemorrhage
5% Subarachnoid (younger people)
stroke risk factors: 7 bigs
aging hypertension cardiac disease hyperlipid DMII hypercoagulability smoking/obesity
Definition of cerebral infarction?
necrosis due to occlusion or hypoperfusion
what vascular structures usually cause of cerebral infarction?
usually arterial
arterioles, veins, heart
3 main mechanisms of cerebral infarction
- pump failure
- narrowed lumen
- emboli occlusion
causes of narrowed lumen in cerebral infarction? 3 things:
- atherosclerosis
- thrombosis
- hypertensive thickening
what is usual cause of large artery occlusions?
embolic
what is usual cause of small vessel occlusions?
thrombosis
what is usual cause of venous occlusions?
thrombotic
what can happen in heart valves to cause stroke? causes?
valve vegetations due to:
- infectious
- non-infectious deformities
1/3 of population has what in their heart that will increase stroke risk?
- patent interatrial septum
2. allows DVTs to pass into brain and skip lungs
Common sites for atherosclerosis in circle of willis? 4 areas
vertebral artery
internal carotid
proximal MCA
basilar
when brain tissue is injured, what happens to area around it?
cytotoxic oedema>increased ICP>herniations (subfalcine or uncal)
dead neurons histologically look?
surrounded by anoxic-ischemic neurons
after swelling recedes in cerebral infarct, what happens to the dead area?
liquidative necrosis>cystic space
what are cerebral haemorrhagic infarcts?
from reperfusion damage, and can come from cardiac ventricle thrombus/emboli
berry aneurysm cause usually?
hypertension causing hyaline arteriolosclerosis
lacunar infarcts are? dangerous where?
small infarcts from hypertension, can be devastating if in brainstem
people with cerebral infarcts die how? top 3:
Usually sequelae
- pneumonia
- cardiovascular disease
- pulmonary thromboembolism (immobility)
hypertensive small vessel disease affects which vessels?
deep structures
congophilic (amyloid) angiopathy affects which vessels?
superficial periphery of brain
hypertensive haemorrhage usually has what disease?
hyaline arteriolosclerosis
hypertensive haemorrhage usually happens where? 4 places
basal ganglia/thalamus
lobar white matter
cerebellum
pons
high pressure cerebral haemorrhage does what?
tear through neural tissue
low pressure cerebral haemorrhage does what?
ooze and then separate cerebral tissue
cerebral amyloid angiopathy has deposition of what? which vessels?
A beta-amyloid plaques in wals of superficial supratentorial blood vessels
cerebral amyloid angiopathy has association with?
alzheimer’s disease
when do you get multifocal synchronous haemorrhages?
coagulopathy, blood disorders (leukaemia)
congenital ateriovenous malformation does what?
high pressure arteries join to low pressure veins without crossing capillaries = haemorrhage
3 causes of subarachnoid haemorrhage?
- berry aneurysm rupture
- other aneurysm rupture (mycotic/atherosclerotic)
- extension of intracerebral haemorrhage
who is more at risk for devloping saccular aneurysm?
women
younger
risk factors for saccular aneurysm? 5 things
- polycystic kidney disease
- coarctation of aorta
- type III collagen deficiency
- hypertension
- smoking/alcohol
saccular aneurysms occur which circulation?
90% anterior circulation
10% posterior
3 places that saccular aneurysms like to form?
- bi-trifurcation of MCA
- junction of ICA/PCOM
- ACOM
4 complications of aneurysm rupture
- subarachnoid haemorrhage
- increase ICP/cerebral oedema
- vasospasm/infarction
- ventricular obstruction>hydrocephalus
