Blood Supply To The Brain

Question 1

What arteries provide 80% of the brain?

Answer 1

The internal carotid arteries

Question 2

What arteries provide 20% of the brain

Answer 2

The vertebral arteries

Question 3

What parts of the brain do the internal carotid arteries supply>

Answer 3

• most of the telencephalon

- much of the diencephalon

Question 4

What parts of the brain do the vertebral arteries supply?

Answer 4

• the brain stem
• the cerebellum
• parts of the diencephalon
• the spinal cord
• occipital and temporal lobes

Question 5

The internal carotid artery is a continuation of what artery?

Answer 5

The common carotid artery

Question 6

Where does the internal carotid artery veer anteriorly?

Answer 6

At the temporal bone

Question 7

What is the small branch the internal carotid artery gives off in the carotid canal?

Answer 7

Ramus caroticotimpanicus

Question 8

What does the internal carotid artery enter the skull through?

Answer 8

The carotid canal

Question 9

The internal carotid artery passes through___________ and the _____________ at the base of the skull

Answer 9

Passes through the cavernous sinus and the subarachnoid space

Question 10

The ophthalmic branch of the internal carotid artery leaves the skull through what?

Answer 10

The superior optic foramen

Question 11

The ophthalmic branch of the internal carotid artery gives rise to what artery?

Answer 11

The central retinal artery

Question 12

What are the two smaller branches the internal carotid artery gives rise to?

Answer 12

• anterior choroidal artery

- posterior communicating artery

Question 13

The continuation of the internal carotid artery is called what?

Answer 13

The middle cerebral artery

Question 14

As the two anterior cerebral arteries enter the longitudinal fissure, they are connected by what?

Answer 14

The anterior communicating artery

Question 15

The anterior cerebral artery curves around __________ to supply __________________

Answer 15

Curves around the corpus callosum to supply the medial parts of the frontal and parietal lobes

Question 16

The anterior cerebral artery continues as what artery?

Answer 16

The pericallosal artery

Question 17

Occlusion of an ACA causes restricted contralateral motor and somatosensory deficits affecting what?

Answer 17

The leg more than any other part of the body

Question 18

The middle cerebral artery proceeds posteriorly in what?

Answer 18

The lateral sulcus

Question 19

The middle cerebral artery emerges from the lateral sulcus to supply what?

Answer 19

Most of the lateral surface of the cerebral hemisphere

Question 20

Occlusion of the MCA causes major motor and somatosensory deficits in what?

Answer 20

The upper body and head

Question 21

If the left hemisphere is involved in the occlusion of an artery, what kind of deficits would be seen??

Answer 21

Language deficits

Question 22

What are lenticulostriate arteries?

Answer 22

12 small branches off of the MCA that penetrate the brain and supply deep structures of the hemispheres

Question 23

Narrow, thin-walled vessels of the anterior perforated substance are involved frequently in what?

Answer 23

Strokesssssssssss

Question 24

The vertebral arteries run rostrally through what?

Answer 24

The foramina of the lateral processes of the spinal vertebrae

Question 25

The vertebral arteries enter the skull through what?

Answer 25

Foramen magnum

Question 26

The vertebral arteries fuse together at the junction between the medulla and pons to form what?

Answer 26

Midline basilar artery

Question 27

What are the three branches of the vertebral arteries?

Answer 27

- posterior spinal artery - anterior spinal artery - posterior inferior cerebellar artery

Question 28

What does the posterior spinal artery supply?

Answer 28

The posterior third of the posterolateral aspect of the spinal cord

Question 29

That anterior spinal arteries fuse to make what?

Answer 29

1 single anterior spinal artery

Question 30

What does he anterior spinal artery supply?t

Answer 30

The anterior 2/3 f the spinal cordo

Question 31

Why must the posterior and anterior spinal arteries be refilled at various points?

Answer 31

They are small and cannot carry enough blood from the vertebral arteries to supply more than the cervical segments of the spinal cord

Question 32

What are the main branches off of the basilar artery?

Answer 32

- anterior inferior cerebellar artery | - superior cerebellar artery

Question 33

What does the basilar artery do at the level of the midbrain?

Answer 33

Bifurcated into the two posterior cerebral arteries

Question 34

What supplies the pons?

Answer 34

Pontine arteries off of the basilar artery

Question 35

The perforating branches off of the posterior cerebral artery supply what?

Answer 35

The thalami

Question 36

Choroidal branches off of the posterior cerebral arteries supply what?

Answer 36

The choroid plexuses od the third and lateral ventricle

Question 37

What supplies the visual cortex?

Answer 37

The medial occipital cortical branch off of the posterior cerebral artery

Question 38

What does the circle of willis connect??

Answer 38

The internal carotid and vertebral-basilar systems

Question 39

Is there normally a lot or a little blood running through the posterior communicating arteries?

Answer 39

A little

Question 40

Technically, if a major vessel becomes occluded in the circle of willis, the communicating arteries would allow flow and prevent damage, but in reality...

Answer 40

The communicating arteries vary in size and are normally not sufficient to ensure functional anastomoses

Question 41

Successful vascular flow rearrangement depends on...

Answer 41

How fast the arterial occlusion occurs

Question 42

Is it normal to have one or more of the communicating arteries extremely small or even absent from the circle of willis?

Answer 42

Sure. Asymmetries are common

Question 43

Where is the venous drainage of the brain located?

Answer 43

Between inner and outer layers of dura mater

Question 44

Blood collected by Duran venous sinuses drains ultimately into what?

Answer 44

The internal jugular veins

Question 45

Why do cerebral veins not have valves?

Answer 45

Because the brain sits above the heart. No need like normal veins

Question 46

What is autoregulation?

Answer 46

Process where cerebral blood vessels act to maintain constant flow

Question 47

Arterial and arteriolar smooth muscle cells are directly stretch sensitive meaning...

Answer 47

Vessels constrict in response to increased blood pressure and they relax in response to decreased pressure

Question 48

An increase in PaCO2 has what impact on vessels?

Answer 48

Vasodilation increases and so does cerebral blood flow.

Question 49

NO is a potent...

Answer 49

Vasorelaxant

Question 50

Acidosis has what impact on vessels?

Answer 50

Vasodilation

Question 51

A cerebral angiography is produced by introducing a catheter where?

Answer 51

Into the femoral artery, threading it up the aorta and then into the artery of choice