Cerebral Vasculature Flashcards
How much of body weight is the brain?
How much of the cardiac output does the brain take?
How much oxygen consumption?
How much liver glucose?
2%
10-20%
20%
66%
What is the major arterial supply to the brain?
What goes through the carotid canal and supplies the anterior side of the brain?
Brachiocephalic continues onto subclavian, what is the first branch of this?
Common carotid artery
Internal carotid artery
Vertebral artery
Name the branches in the diagram
How does blood leave the brain?
Venous drainage
Cerebral veins –> Venous sinuses in the dura mater –> Internal jugular vein
Name the dural veous sinuses
y
What is the subdural space?
What is a subdural bleed?
Cause?
Space between the inner dura layer and the arachnoid layer
Bleed in this space and is venous, so is not high pressure as there is already a space so there might not be symptoms / symptom lag
Trauma, can be delayed clinical effects (venous, lower pressure)
What is found in the subarachnoid space?
What is the cause of a subarachnoid bleed
All the CSF is found as well as vessels
Usually a burst/ruptured aneurism ; weakness in one of the basal vessel walls; congenital
What is a intracerebral bleed?
Bleed in the brain tissue itself
Seen commonly in patients who are hypertensive
What bleed is shown?
Subdural;
Dura is on the outside and a massive blood clot inside
What bleed is shown?
Intracerebral bleed;
Probably due to poorly maintained hypertension
What bleed is shown?
Extradural bleed;
Arterial bleed accumulated outside dura
What bleed is shown?
Subarachnoid;
Covered in blood and goes everywhere as CSF is also there
What is a stroke?
Cerebrovascular accident (CVA)
Definition: “rapidly developing focal disturbance of brain function of presumed vascular origin and of >24 hours duration”
Thrombo-embolic (85%) or haemorrhage (15%)
Transient ischaemic attack (TIA)?
“rapidly developing focal disturbance of brain function of presumed vascular origin that resolves completely within 24 hours”
Infarction?
Degenerative changes which occur in tissue following occlusion of an artery
Cerebral ischaemia?
Lack of sufficient blood supply to nervous tissue resulting in permanent damage if blood flow is not restored quickly
Thrombosis?
formation of a blood clot (thrombus)
Embolism
plugging of small vessel by material carried from larger vessel e.g. thrombi from the heart or atherosclerotic debris from the internal carotid
FAST for stroke? What does it stand for?
Face
Arms
Speed
Time
What are the risk factors for stroke?
Age
Hypertension
Cardiac disease
Smoking
Diabetes mellitus
What is the perfusion field of the posterior cerebral artery?
What is the perfusion field of the middle cerebral artery?
What is the perfusion field of the anterior cerebral artery?
Occipital lobe and inferior part of temporal lobe
Lateral surface of brain and most of the deep structures
Front and a strip of tissue to the parieto - occipital notch
Sagittal view - parietal lobe as well
What symptoms do damage to the anterior cerebral artery lead to?
Paralysis of contralateral structures (leg > arm, face)
Disturbance of intellect, executive function and judgement (abulia)
Loss of appropriate social behaviour
What symptoms do damage to the middle cerebral artery lead to?
“Classic stroke”
Contralateral hemiplegia – weakness rather than complete paralysis: arm > leg
Contralateral hemisensory deficits
Hemianopia: visual system
Aphasia (L sided lesion) - speech
What symptoms do damage to the posterior cerebral artery lead to?
Visual deficits
-homonymous hemianopia
-visual agnosia
What major risk factor for stroke is evident in this specimen?
The yellow discolouration in the walls of the vessels is a build-up of atheroma, fatty deposits that cause atherosclerosis or “hardening of the arteries”
Which cerebral artery has been occluded in this specimen?
The marked area shows
evidence of infarction in the
perfusion field of the right
middle cerebral artery
