Cerebrovascular Disease Pathology Flashcards
Which cerebral vessel is most commonly affected in thromboembolic disease, mainly because of its position?
MCA
What is the important overlying process which can result in both ischaemic and haemorrhagic strokes?
Hypertension
What is global hypoxic ischaemic damage?
When the systemic compromise to circulation (e.g. cardiac arrest, hypovolaemic shock) cannot be compensated for by CNS autoregulatory mechanisms
Global hypoxic ischaemic damage occurs when MAP reaches what level? What is the significance of this?
50mmHg - this is when autoregulatory mechanisms cannot sufficiently compensate
What are watershed areas?
Areas at the peripheries of vascular territories
Why do watershed areas contain neurones which are particularly sensitive to hypoxia?
Because they are the most distant from the heart, and the least well supplied
Which type of cell found in the CNS is more sensitive to hypoxic damage - neurones or glial cells?
Neurones
What is focal ischaemia?
Restriction of blood flow to a localised area of the brain, typically due to a vascular obstruction
The presence of atheroma in both intra and extra cerebral blood vessels is a risk factor from stroke. Atheroma can affect all the main cerebral arteries but in general, which is most commonly affected?
Basilar artery
Atheroma formation in the extracranial vessels (e.g. carotids and aorta) is significant as these are the source of the majority of which type of stroke?
Embolic
Describe why hypertension is a risk factor for both ischaemic and haemorrhagic stroke?
Ischaemic - contributes to atheroma formation and atherosclerosis Haemorrhagic - increases the chance of spontaneous rupture of vessels
In an ischaemic stroke, after how long will the necrotic area become visible macroscopically?
48 hours
After an ischaemic stroke, what will always remain macroscopically as a permanent marker of the site of an old infarction?
Gliotic scar to start with which will desist to become a cystic gap
Microscopically, what is the primary cell type seen within 48 hours of an ischaemic stroke?
Neutrophils
Microscopically, what is the primary cell type seen after 48 hours of an ischaemic stroke?
Microglia
Around a week after an ischaemic stroke, what pathological process takes place microscopically? What happens?
Reactive gliosis - astrocytes increase in number and size
A few weeks after an ischaemic stroke, a cavity begins to form microscopically which is lined by what?
Gliotic scar tissue characterised by astrocytes