Blood Supply to the Brain Flashcards
- what is ~ avergae brain blood flow? [1]
- does this fluctuate much (e.g. with hyper /hypotension)? [1]
- what changes in O2 [1] & CO2 [1] cause an increase in blood flow to brain?
- what is ~ avergae brain blood flow? [1] ~ 50 ml per 100g of brain tissue per minute
- does this fluctuate much (e.g. with hyper /hypotension)? [1]
- *no: flow regulated by auto-regulation**
- what changes in O2 [1] & CO2 [1] cause an increase in blood flow to brain?
decrease in o2
increase in co2 = both increase flow to brain
what is different about cerebral arteries compared to other arteries? [3]
what is different about cerebral veins compared to other veins? [3]
arteries
- thin walled
- easily blocked
- easily distorted & ruptured
veins:
- no valves
- thin walled
- gravity helps flow back
- found in dural sinuses
which arteries provide 80% of total cerebral blood flow to anterior 2/3 cerebral cortex?
which arteries provide 20% of total cerebral blood flow to posterior 1/3 cerebral cortex?
which arteries provide 80% of total cerebral blood flow to anterior 2/3 cerebral cortex?
internal carotid arteries
which arteries provide 20% of total cerebral blood flow to posterior 1/3 cerebral cortex?
vertebral arteries
ICA: branch into: anterior cerebral artery (goes anterior & 2 are connected by anterior communicating artery) & middle cerebral artery
posterior blood supply:
- vertebral arteries come in & merge to form basilar artery. at midbrain, basilar artery –> posterior cerebral artery
which of the following is formed from basilar artery:
anterior spinal artery
middle cerebral artery
posterior cerebral artery
posterior inferior cerebellar artery
anterior cerebral artery
which of the following is formed from basilar artery:
anterior spinal artery
middle cerebral artery
posterior cerebral artery
posterior inferior cerebellar artery
anterior cerebral artery
what is D?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is C?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is A?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is A?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is E?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is E?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is C?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is C?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is B?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
what is B?
middle cerebral artery
basilar artery
posterior cerebral artery
anterior cerebral artery
internal carotid artery
draw the circle of willis xxx
Label A-C
A: anterior cerebral artery
B: middle cererbral artery
C: internal carotid artery
under normal circumstances, what are the anterior and posterior communicating arteries like?
closed !!
classic circle of willis is seen in ~1/3rd pop
label A-D [4]
A: vertebral artery
B: superior cerebellar artery
C: posterior cerebral artery
D: basilar artery
when does collateral circulation open? [1]
collateral circulation should only open when there is a pressure difference (increased pressure can open anterior / posterior communicating arteries)
what is most normal variant in cerebral arterial circle? [1]
what is most normal variant in cerebral arterial circle? [1]
one / both posterior communicating arteries are missing (e & f)
what are the main branches of the internal carotid artery? [4]
- opthalmic artery: orbit & retina. connects to external carotid artery
- posterior communicating: connext with carotid & vertebral artery system
- middle cerebral artery: connects to basal ganglia and lateral 2/3rds of cortex
- anterior cerebral artery: connects with medial side frontal & parietal lobes, anastamoses with MCA
which artery is a branch of the ICA that occurs in the cavernous sinus?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which artery is a branch of the ICA that occurs in the cavernous sinus?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the basal ganglia & lateral 2/3rd of the cortex?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the basal ganglia & lateral 2/3rd of the cortex?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the medial side of frontal and parietal lobes?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the medial side of frontal and parietal lobes?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following anastamoses with the MCA?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following anastamoses with the MCA?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following connects to the external carotid artery?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following connects to the external carotid artery?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the corpus callosum?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
which of the following supplies the corpus callosum?
middle cerebral artery
anterior cerebral artery
posterior communicating artery
menigeal branch
opthalmic artery
what is A?
cavernous sinus
middle cerebral artery goes between which two brain lobes to get to lateral wall?
temporal & parietal
temporal and occiptal
temporal and frontal
parietal and occipital
occipital and cerebellum
middle cerebral artery goes between which two brain lobes to get to lateral wall?
temporal & parietal
temporal and occiptal
temporal and frontal
parietal and occipital
occipital and cerebellum
which artery most commonly supplies Broca’s & Wernicke’s areas?
ACA
MCA
PCA
Basilar A
ICA
which artery most commonly supplies Broca’s & Wernicke’s areas?
ACA
MCA
PCA
Basilar A
ICA
which arteries supply 1-5?
1: anterior cerebral A
2: middle cerebral A
3: posteror cerebral A
4: anterior choroidal A
5: lenticulostriate (branch of MCA)
describe the pathway of the posterior circualation of the brain?
vertebral:
- has anterior spinal arteries and posterior spinal arteries (x2) going inferiorly
- has PICA branching off to dorsal medulla of brainstem
turns into the basilar artery:
- has anterior inferior cerebellar artery (AICA) and superior cerebellar artery arching off
redivides at the superior cerebellar arteries and continues to **posterior cerebral arteries
- **supplies the inferior and medial aspects of temporal and occipital cortex
- thalamus
- midbrain
- anastamoses with MCA
which artery provides blood to the pons?
PICA
AICA
superior cerebllar artery
pons
posterior cerebral artery
which artery provides blood to the pons?
PICA
AICA
superior cerebllar artery
pons (via pontine arteries)
posterior cerebral artery
which artery provides blood to the midbrain & thalamus
PICA
AICA
superior cerebllar artery
pons
posterior cerebral artery
which artery provides blood to the midbrain & thalamus
PICA
AICA
superior cerebllar artery
pons
posterior cerebral artery
which artery provides blood to the dorsal medullar of midbrain?
PICA
AICA
superior cerebllar artery
pons
posterior cerebral artery
which artery provides blood to the dorsal medullar of midbrain?
PICA
AICA
superior cerebllar artery
pons
posterior cerebral artery
which of the following is the vertebral artery?
A
B
C
D
E
which of the following is the vertebral artery?
A
B
C
D
E
which of the following is the PICA?
A
B
C
D
E
which of the following is the PICA?
A
B
C
D
E
which of the following is the anterior spinal artery?
A
B
C
D
E
which of the following is the anterior spinal artery?
A
B
C
D
E
which of the following is the basilar artery?
A
B
C
D
E
which of the following is the basilar artery?
A
B
C
D
E
which of the following is the AICA?
A
B
C
D
E
which of the following is the AICA?
A
B
C
D
E
what do arachnoid granulations allow to occur? [1]
arachnoid granulations: allow CSF to flow into venous blood of sinuses but prevent backflow of blood into sub-arachnoid space
which sinus do most cerebral veins drain into?
straight sinus
transverse sinus
superior saggital sinus
inferior saggital sinus
sigmoid sinus
which sinus do most cerebral veins drain into?
straight sinus
transverse sinus
superior saggital sinus
inferior saggital sinus
sigmoid sinus
which of the following is the straight sinus?
A
B
C
D
E
which of the following is the straight sinus?
A
B
C
D
E
which of the following is the sigmoid sinus?
A
B
C
D
E
which of the following is the sigmoid sinus?
A
B
C
D
E
which of the following is the superior sagittal sinus?
A
B
C
D
E
which of the following is the superior sagittal sinus?
A
B
C
D
E
which of the following is the transverse sinus?
A
B
C
D
E
which of the following is the transverse sinus?
A
B
C
D
E
which of the following is the inferior sagittal sinus?
A
B
C
D
E
which of the following is the inferior sagittal sinus?
A
B
C
D
E
which CN do you find in the cavernous sinus? [4]
CN III
CN IV
CN V1
CN V2
CN VI (more medial)
posterior spinal arteries come off which arteries? [1]
anterior spinal artery comes off which artery? [1]
posterior spinal arteries come off which arteries? [1]
PICA
anterior spinal artery comes off which artery? [1]
verterbral artery
which artery reinforces the circulation of 2/3rs of spinal cord?
where does it come from?
which artery reinforces the circulation of 2/3rs of spinal cord?
greater segmental medullary artery (artery of Adamkiewicz)
where does it come from?
branch of intercostal artery
what might happen to patients undergoing surgery for an arotic aneursym? [1]
what might happen to patients undergoing surgery for an arotic aneursym? [1]
may lose all sensation and vol. movement inferior to level of occlusion
where is most common place for cerebral aneursym? [1]
when are they dangerous? [1]
anterior communicating artery
when are they dangerous? [1]
when they rupture
what are the two different types of stroke? [2]
* what happens if you have stroke to MCA in dominant hemisphere? [2] *
* what happens if you have stroke to MCA in non-dominant hemisphere? [1] *
ischaemic: blood clot to artery supplying brain
hamorrhagic stroke: small bleed out into blood tissue
* what happens if you have stroke to MCA in dominant hemisphere? [2] *
- *global aphasia (**bc Broca & Wernickes area’s get damaged)
- *sensorimotor loss on controlateral face, upper limb & trunk**
* what happens if you have stroke to MCA in non-dominant hemisphere? [1] *
neglect syndrome (only will draw half of image)
what would u see if had stroke to ACA? [4]
what would u see if had stroke to ACA? [4]
- contralateral sensorimotor loss below waist
- urinary incontinence
- personaility defects
- split brain syndrome (corpus callosum gets damaged)
what would u see if had stroke to PCA? [3]
what would u see if had stroke to PCA? [3]
- contralateral homonymous hemianopsia (image)
- reading & writing deficits
- impaired memory
what would happen if PICA is blocked / burst?
lateral medullary syndrome: wallenburg syndrome
suddenly:
- vertigo, horners syndomr, nauseau, loss of pain and temp on contralateral, loss of pain and temp in face (trigeminal)
