Blood supply

Question 1

What are the types of strokes

Answer 1

• Transient ischemic attack TIA
• Infarction
• hemmorrhage

Question 2

What are the two systems that supply blood to the brain?

Also what does each system supply

Answer 2

• Anterior: carotid system; supples the cerebrum
• Posterior: vertebral-basilar system; supplies spinal cord, brainstem and cerebellum

Question 3

What arteries are involved in the posterior circulation?

Answer 3

• Vertebral artery
• basilar artery
• anterior spinal artery
• posterior spinal artery
• posterior-inferior cerebellar artery
• anterior inferior cerebellar artery
• superior cerebral artery
• posterior cerebral artery

Question 4

Vertebral-basilar system

describe vertebral arteries

Answer 4

• subclavian arteries each form one vertebral artery
• vertebral artery supplies the medulla
• vertebral arteries travel on either side of the cervical spinal cord, enter skull and join to form basilar artery

Question 5

What does the vertebral artery supply and how can they be damaged?

Answer 5

• brainstem laterally/more anterior (vertebral-basilar system)
• abrupt neck rotation or hyperextension

Question 6

Prior to vetebral arteries joint to form the basilar artery what are the branches that come off?

Answer 6

• anterior spinal artery
• posterior spinal artery
• posterior inferior cerebrallar artery

Question 7

What does the anterior spinal artery supply?

also what happens with an infarct

Answer 7

• anterior 2/3 of spinal cord
• medial medulla
• medial medullary syndrome with infarct

Question 8

What does the posterior spinal artery supply?

what happens with an infarct?

Answer 8

• Posterior 1/3 of spinal cord
• dorsal Medulla lower medulla
• dorsal lateral medulla syndrome

Question 9

What does the Posterior inferior cerebellar artery supply?

Answer 9

• Posterior inferior cerebellum
• Medulla (dorsolateral)
• Lateral medulla/cerebellar and vestibular issues (wallenberg syndrome)

Question 10

Basilar artery

Answer 10

• formed by the two vertebral arteries
• Runs from pontomedullary junction to midbrain

Question 11

what would occur with a blockage of ASA in the medulla?

Answer 11

• medial medullary syndrome
• contralateral weakness
• DCML is damaged slightly

Question 12

What would occur with an infarct to PICA or vertebral arteries in medulla

Answer 12

• lateral medullary syndrome = wallenberg’s syndrome
• ipsilaterally ataxia, vertigo and sensory changes

Question 13

Branches of the basilar artery

Answer 13

• anterior inferior cerebrellar artery (AICA)
• superior cerebellar artery
• at end branches to form posterior cerebral arteries (primary source to midbrain)

Question 14

What does the anterior inferior cerebellar artery supply?

Answer 14

• lateral pons
• anterior, inferior cerebellum

Question 15

What does the superior cerebellar artery supply?

Answer 15

• superior cerebellar peduncles
• superior cerebellum

Question 16

What does the posterior cerebral artery supply

Answer 16

-primary source for the midbrain

Question 17

How does the basilar artery supply the pons

Answer 17

• paramedian branches
• long circumferential arteries
• short circumferential arteries

basilar artery infarct = locked in syndrome

Question 18

What does the posterior cerebral artery supple

Answer 18

• midbrain
• thalamus
• hippocampus important for memory
• medial, inferior temporal lobe
• occipital lobe

Question 19

Origin of the carotid system

Answer 19

• aorta
• left side = common carotid artery
• right side = brachiocephalic artery branches into common carotid
• both common carotid arteries branch into internal and exteneral caroitd arteries

Question 20

Internal carotid

Answer 20

• internal carotid enters the brain through temporal bone of the skull
• branches into anterior cerebral artery, middle cerebral artery

Question 21

Anterior cerebral artery

supplies

Answer 21

• parts of the caudate
• putamen
• globus pallidus
• internal capsule
• corpus callosum
• anterior, medial frontal lobe
• medial parietal lobe

caudate, putamen, globus pallidus = basal ganglia

Question 22

Infarct to the anterior cerebral artery

Answer 22

Infarct includes

• frontal lobe dysfunction
• contralateral hemiplegia and hemisensory loss,
• LE>UE-medial sensorimotor cortex affected
• incontinence

Question 23

What does the middle cerebral artery supply

Answer 23

• Parts of the caudate and internal capsule
• most of lateral hemisphere of cortex
• brocas area is typically on the left

Question 24

Infarct to the middle cerebral artery

Answer 24

• Very common CVA. Many impairments.

Include:

• Contralateral hemiplegia and hemisensory loss (UE and Face-lateral sensorimotor cortex affected-see next slide),
• aphasia (if lesion in in language dominant side-usually left),

Question 25

what is the circle of willis

Answer 25

- Connects caroitd and vertebral-basilar systems - can provide a shunt if there is temporary loss of ciriculation - important for blood supply to thalamus, internal capsule, and basal ganglia

Question 26

What arteries form the circle of willlis

Answer 26

- posterior cerebral arteries - posterior communicating arteries - internal carotid arteries - anterior cerebral arteries - anterior communicating arteries

Question 27

Aneurysm of the circle of willis

Answer 27

- Anterior communicating artery walls tend to be weaker - over time this weaker part of the vessel can expand espeically with HTN - can result in a hemorrhage

Question 28

Anterior chordoidal

Answer 28

- branch of internal carotid Supplies: - choroid plexus (makes CSF - parts of visual pathway - putamen - thalamus - internal capsule - hippocampus

Question 29

Anastomosis

Answer 29

- . communication between cerebral blood vessels by collateral channels. - Lie within sulci - Unite branches of the 3 major cerebral arteries end to end (MCA, PCA, ACA)

Question 30

Watershed CVA

Answer 30

- occurs with severe drops in BP - maximal BP is required from blood to reach the terminal ends of the arteries where the vessels have the smallest diameter