Blood supply to the brain

Question 1

What are the effects of hypoglycaemia to the brain?

Answer 1

mood change, confusion, dizziness. fainting

Question 2

What are the symptoms of oxygen starvation to the brain?

Answer 2

light headedness, confusion, cyanosis, loss of consciousness, coma

Question 3

What is unusual about brain arteries?

Answer 3

There are no anastamoses or safety methods for if blood supply is disrupted

Question 4

How soon can neurons in an oxygen starved area become damaged?

Answer 4

As soon as 3 mins

Question 5

What supplies the anterior brain?

Answer 5

the internal carotid arteries

Question 6

What supplies blood to the posterior brain?

Answer 6

The vertebral arteries

Question 7

How does the internal carotid enter the skull?

Answer 7

via the carotid canal

Question 8

How do the vertebral arteries enter the skull?

Answer 8

via the foramen magnum

Question 9

Where do the external carotid arteries arise?

Answer 9

from the carotid arteries

Question 10

What is the role of the external carotid arteries?

Answer 10

Remain outside the skull and deliver oxygenated blood to the face, scalp, tongue, teeth, gums, sinuses, middle/external ear, pharynx, larynx, thyroid

Question 11

What is the basilar artery?

Answer 11

The point at which the right and left vertebral arteries merge

Question 12

Where is the basilar artery found?

Answer 12

At the pons

Question 13

What branches come off the basilar artery?

Answer 13

those which supply the brainstem and the medulla

Question 14

What happens at the point that the basilar artery terminates?

Answer 14

divides into the right and left posterior cerebral arteries (PCA)

Question 15

What do the posterior cerebral arteries (PCA) supply?

Answer 15

the occipital lobe (including visual cortex) and inferior temporal lobe of each hemisphere

Question 16

Where do the internal carotid arteries branch?

Answer 16

almost immediately as they enter the skull

Question 17

What do the internal carotids divide into?

Answer 17

the middle cerebral artery and the anterior cerebral artery

Question 18

What doe the middle cerebral artery supply?

Answer 18

most of the lateral surface of the frontal, parietal and temporal lobes

Question 19

What corticies are supplied by the middle cerebral arteries?

Answer 19

motor, sensory, auditory, Wernickes, Brocas

Question 20

How are teh right and left anterior cerebral arteries connected?

Answer 20

By the anterior communicating arteries

Question 21

What does the anterior cerebral artery supply?

Answer 21

1. 1cm strip on the superior edge of each hemisphere laterally
2. medial surface of the frontal and parietal lobes

Question 22

How does the vertebrobasilar system communocate with the internal carotid system?

Answer 22

Through the arterial circle of Willis

Question 23

What forms the circle of Willis?

Answer 23

1. One anterior communicating artery between the anterior cerebral arteries
2. Two posterior communicating arteries between posterior cerebral arteries and internal carotids (or their branches)

Question 24

How many people have all three communicating arteries?

Answer 24

About 60%

Question 25

When can the circle of Willis operate as compensatory blood flow?

Answer 25

If the major blood vessels are obstructed before they reach the arterial circle

Question 26

Where do the perforating arteries arise?

Answer 26

From the three pairs of arteries as they leave the circle of Willis on the underside of each hemisphere

Question 27

What do the perforating arteries supply?

Answer 27

thalamus, internal capsule, basal ganglia

Question 28

What are the features of the perforating arteries?

Answer 28

They are small and prone to CVA