Neuro - Cerebral Vasculature Flashcards
How much cardiac output does the brain use?
10-20%
How much body O2 does the brain consume?
20%
How much liver glucose does the brain consume?
66%
What are the 2 main blood supplies to the brain?
→ internal carotid artery (off the common carotid artery)
→ vertebral artery (off the subclavian artery)
How are the arteries of the brain arranged?
in Circle of Willis → from vertebral arteries → basilar artery → posterior cerebral arteries → posterior communicating arteries → middle cerebral arteries → internal carotid arteries → anterior cerebral arteries → anterior communicating arteries
How does the venous drainage of the brain work?
→ cerebral veins
→ venous sinuses in dura mater
→ internal jugular vein
What are the 4 types of inter-cranial haemorrhages?
→ extradural : trauma, immediate clinical effects (arterial, high pressure)
→ subdural : trauma, can be delayed clinical effects (venous, lower pressure)
→ subarachnoid : ruptured aneurysms
→ intracerebral : spontaneous hypertensive
What is a stroke (CVA)?
→ cerebrovascular accident
→ rapidly developing focal disturbance of brain function of presumed vascular origin and of >24hrs duration
What are the two types of strokes?
→ thrombo-embolic (85%)
→ haemorrhage (15%)
What is a TIA?
→ transient ischaemic attack
→ rapidly developing focal disturbance of brain function of presumed vascular origin that resolves in 24 hours
→ warning of a spossible stroke in the future
What is the definition of an infarction?
degenerative changes which occur in tissue following occlusion of an artery
What is cerebral ischaemia?
lack of sufficient blood supple to nervous tissue resulting in permanent damage if blood flow is not restored quickly
What is thrombosis?
formation of a blood clot (thrombus)
What is embolism?
→ plugging of smaller vessels by material carried from larger vessel
→ e.g. thrombi from heart or atherosclerotic debris from internal carotid
What is FAST campaign for strokes?
→ F = face fallen on one side
→ A = arms, unable to hold them up
→ S = speech slurred
→ T = time to call 999
What are the risk factors for strokes?
→ age → hypertension → cardiac disease → smoking → DM
Which cerebral artery has the biggest perfusion field?
middle cerebral artery
What are symptoms of anterior cerebral artery strokes?
→ paralysis of contralateral structures
→ disturbance of intellect, executive function + judgement (abulia)
→ loss of appropriate social behaviour
What are symptoms of middle cerebral artery strokes?
→ “classic stroke”
→ contralateral hemiplegia (paralysis of half body, arm > leg)
→ contralateral hemisensory deficits (loss of sense son half of body)
→ hemianopia (loss of one half of visual field)
→ aphasia (L sided lesion)
What are symptoms of posterior cerebral artery strokes?
visual deficits
→ homonymous hemianopia (loss of visual fields)
→ visual agnosia (inability to recognise things)
Name a-c in this picture.
Name all the structures in this diagram.
Name the structures in this diagram.
What kind of intercranial haemorrhage is this?
What kind of intercranial haemorrhage is this?
What kind of intercranial haemorrhage is this?
What kind of intercranial haemorrhage is this?
What major risk factor for stroke is evident here?
Which cerebral artery has been occluded in this specimen?
Right middle cerebral
What are the features of an extradural haemorrhage?
Trauma
Immediate clinical effects
Arterial bleed, high pressure
What are the features of a subdural haemorrhage ?
Trauma
Can have delayed clinical effects
Venous bleed, lower pressure
What are the features of a subarachnoid haemorrhage?
Usually ruptured aneurysms
What are the features of an intracerebral bleed?
Spontaneous + hypertensive
