Pathology of Crebro-vascular disease Flashcards
(19 cards)
Brainsupply of the brainstem
vertebral arteries and basilar artery
What is the middle cerebral artery a continuatio of?
the internal carotid(s)
What is iscahemia? Hypoxia?
ischaemia = low blood flow
hypoxia = low oxygen
What are the 3 main causes of localised interrupted blood supply?
-Atheroma and thrombosis
thromboembolus
anneurysm rupture
What can happen to an atheroma to severely narrow the lumen of artery?
get thrombosis ->severly narrowed
What issue in the vessles could a tia be due to?
stenosis and ischaemia due to atheroma and thrombosis of the carotics
How long in brain before hypoxia/anoxia?
a few minutes
What s classically wedge shapped infarct due to?
Localised area of brain death - regional cerebral infarct.
Reflects where an artery supplies, so usually due to no/too little blood flow through that artery
What is gliosis?
fibrosis in the brain, due to the glial cells.
WHy do cerebral arteries hprone to aneurysims? WHy?
Because they are thinned walled, because they don’t need the muscle around them to constrict and divert blood because the brain always needs perfusion.
What happens when an artery ruptures (2)
the blood flows out and so compresses the surrounding brain tissue. the vessel goes into spasm and this reduces the blood supply
2 common sites of ruptures?
Basalganglia - microaneurysms in hypertensive patients
Circle of Willis - Berry aneurysm (also more common in hypertensive patients)
What is a berry aneurysm?
it looks like a berry?!
What cna aberry aneyrysm bleed lead to?
sub arachnoid haemorrhage
What are some causes of low o2 in blood?
CO2 poisoning
Respiratory failure
Near drowning
What can cause inadequate supply of blood flow?
Cardiac arrest, hypotension, brain swelling
Give 3 eg of brain injury caused by generalised interrupted blood supply and/or hypoxia
Hypotension
Cardiac arrest
Complex case
What causes watershed infarcts
Hypotension and so reduced perfusion of the brain, which is exacerbated further away from the cerebral arteries, and so causes ischaemia and infaction in the distal regions supplied by the middle, posterior and frontal arteries , causing infarction on the borders between areas supplied
Whatr causes laminar cortico necrosis?
necrosis due to total anoxia of the brain, on the outsides
