7

Question 1

What is very different about the path brain blood supply and systemic blood supply?

Answer 1

-large branches are found on the outside and then smaller branches penetrate in.
- It is a regional supply rather than segmental
-Anastomoses are limited
-

Question 2

Arteries are found in the subarachnoid, but what layer are they covered by?

Answer 2

pia separated by perivascular space, pail coat perforations increase as they get deeper

Question 3

how much blood flow through brain per minute?

Answer 3

approx. 1 liter

Question 4

What is the cerebral perfusion pressure maintained at by auto regulation?

Answer 4

70-90 mmHg

Question 5

What does lack of anastomoses lead to?

Answer 5

occlusion will lead to ischemia

Question 6

Blood flow is not affected in a vessel until how much of it is occluded?

Answer 6

75%

Question 7

The anterior spinal artery runs in?

Answer 7

ventral median fissure

Question 8

Post spinal arteries run near?

Answer 8

dorsal roots

Question 9

What 3 large arteries give rise to radicular arteries?

Answer 9

vertebral, posterior intercostal, lumbar–when they form an anastomoses they are called spinal medullary arteries

Question 10

Where is the major watershed zone in the spine and what artery is important in giving blood to the area?

Answer 10

C8-T9–Great Radicular Artery of Adamkiewicz (gives blood to lower 2/3 of spinal cord)

Question 11

Each internal carotid supplies how much blood to brain?

Answer 11

40%

Question 12

The combined supply of vertebral arteries provide how much blood?

Answer 12

20%

Question 13

In which direction does the internal carotid pass through the cavernous sinus?

Answer 13

anteriorly

Question 14

What are the terminal branches of internal carotid?

Answer 14

anterior cerebral artery and middle cerebral artery

Question 15

What forms the basilar artery?

Answer 15

anastomoses of the vertebral arteries

Question 16

What artery does most clots from heart travel up?

Answer 16

left common carotid- left side strokes more common

Question 17

What is the largest territory covering artery in the brain–what does it cover?

Answer 17

MCA- lateral portions of parietal, temporal and frontal lobes

Question 18

Blockage of the MCA appears as?

Answer 18

widespread infarction lateral side—-secondary branches lead to pie wedge looking infarcts

Question 19

What is referred to as the artery of cerebral hemorrhage?

Answer 19

most lateral lenticulo-striate branches of MCA—-putamen, caudate, basal ganglia, internal capsule

Question 20

What parts of the body are often effected in MCA strokes?

Answer 20

paresis of contralateral face and upper limb—sensory loss from corresponding areas

Question 21

Where are the anterior cerebral arteries joined at?

Answer 21

anterior communicating artery before they head towards occipital lobe through the inter hemispheric fissure

Question 22

What artery supplies motor and sensory below the hip?

Answer 22

ACA—perineum also

Question 23

What does the anterior choroidal artery supply?

Answer 23

internal structures-thalamus, amygdala, hippocampus, globus pallidus, optic tract, lateral geniculate body, choroid plexus of lateral ventricles

Question 24

Before joining of vertebral arteries to form basilar artery they give branches for what?

Answer 24

anterior spinal artery

Question 25

What are the 3 basic branches coming off of the basilar artery?

Answer 25

paramedian, short circumferential, long circumferential

Question 26

What 4 arteries make up the long circumferential arteries?

Answer 26

PICA, AICA, superior cerebellar artery, and a pair of posterior choroidal arteries

Question 27

What arteries are where the basilar artery terminates and what do they supply?

Answer 27

PCA- supplies medial surface of the occipital lobe and inferior lower lateral temporal lobe

Question 28

What branches supply the visual cortex?

Answer 28

calcimine branch of PCA

Question 29

Where is blood passed through in the case of a unilateral carotid occlusion?

Answer 29

blood from intact passes through anterior communicating artery

Question 30

In a bilateral carotid occlusion where is blood passed through?

Answer 30

basilar artery through the posterior communicating arteries

Question 31

In the case of bilayer vertebral occlusion, where is blood passed through?

Answer 31

carotid through posterior communicating artery to basilar

Question 32

Why do 60-70% of patients with unilateral occlusion still show signs of injury even with anastomoses?

Answer 32

the circle of willis is not symmetrical

Question 33

Where can extra cranial anastamoses come into play in the brain?

Answer 33

opthalmic artery and facial artery

Question 34

What causes ischemic stroke in watershed zones?

Answer 34

systemic hypotension/brain hypo perfusion

15-20% of open heart surgeries

Question 35

Is gray or white matter mainly effected in watershed stroke?

Answer 35

white

Question 36

What does MCA and ACA watershed encompass?

Answer 36

proximal upper limbs- bilateral infarct means he cannot abduct arms or flex elbow…man in a barrel syndrome (brachial diplegia)

Question 37

Sympathetics from what ganglion effect cerebral blood flow?

Answer 37

cervical ganglion

Question 38

parasympathetics from what ganglia effect cerebral blood flow?

Answer 38

pterygopalatine ganglion

Question 39

Where are most aneurysms?

Answer 39

circle of willis—anterior circulation