Pathology of Cerebrovascular Disease Flashcards
Do veins travel with arteries in the brain?
No they are not in tandem
What are the main venous structures in the brain?
Large venous sinuses within the dura
How are the venous sinuses fed and how do these vessels travel?
By bridging veins from the brain, they cross the meninges from the brain towards the skull
How are veins linked to those outside the skull?
Emissary veins
What is the Who definition of stroke?
Focal neurological deficit due to disruption of its blood supply
What is the most common cause of stroke?
Ischaemic stroke - vessel blocked by thrombus
What percentage of strokes are haemorrhagic due to a ruptured vessel?
10%
What are the major features of stroke?
Sudden weakness or numbness of the face, arm or leg most often on one side of the body
Other -
Confusion/speech difficulties
Difficulty seeing
Headache
What are the three major categories of stroke?
TIA - last 24 hours but minor neuro deficit
Disabling stroke - >24 hours with persisting disability that impairs independence
What portion of the CO is dedicated to the cerebral blood flow?
15%
Are neurons in the brain able to regenerate after damage|?
No
How many strokes have the potential for thrombolysis?
85%
What is Virchow’s triad of occlusion?
Change in vessel wall
‘’ flow
‘’ content
Give some causes of CNS ischaemia
Atherosclerosis Thrombosis Embolism Hypotension - MI, massive blood loss Arterial spasm following subarachnoid haemorrhage Systemic vascular disease e.g. arteritis Mechanical compression Venous obstruction
What artery is most commonly blocked causing a regional infarction?
Middle cerebral artery
What is acute cerebral cortex ischaemia?
Ischaemia affecting the cerebral hemispheres and the internal capsule. There is contralateral hemiparesis or other signs
May result in loss of brain tissue and cyst
What is useful when determining whether the ischaemia is thrombotic or embolic?
Whether there are pro-thrombotic underlying features like arteriosclerosis, smoking, diabetes
Whether there is a probable source of embolus like cardiac arrhythmia or thoracic aortic aneurysm
Consider whether there is one singe large embolus or multiple smaller infarcts
What is watershed infarction?
When a particular artery is occluded, the perfusion territory of the artery is particularly affected creating zonal patterns of ischaemia and infarction
Outline the pathogenesis of haemorrhagic stroke?
Rupture of a small artery, usually at a bifurcation leading to catastrophic haemorrhage
What proportion of stokes are haemorrhagic?
15%
Where are the vast majority of intracerebral haemorrhage?
Basal ganglia - 80%
Describe the process of subarachnoid haemorrhage
Rupture of saccular (Berry) aneurysm on circle of Willis
Usually a branching point of the anterior part of the circle - internal carotid, anterior communicating, middle cerebral most common
What are the three arteries most commonly the location of a Berry aneurysm?
Internal carotid
Anterior communicating
Middle cerebral
What are the consequences of intracranial haemorrhage?
Death due to rapid increase in intracranial pressure - especially sub arachnoid
