lecture 5: blood supply

Question 1

what are the two primary sources of blood to the brain bilaterally

Answer 1

1) internal carotid arteries (anterior system, 80%)
2) vertebral arteries (posterior system, 20%)

Question 2

in what foramen do the vertebral arteries pass

Answer 2

transverse foramina

Question 3

the common carotid bracnhes off what

Answer 3

either the aorta or the brachiocephalic trunk

Question 4

the common carotid splits into what

Answer 4

internal and external carotid aa

Question 5

true or false: the external carotid arteries provide primary blood supply to the. brain

Answer 5

false, interior

Question 6

the subclavian a branches off what

Answer 6

the aorta

Question 7

what early branch of the subclavian a is considered a primary source of blood supply to the brain

Answer 7

vertebral a

Question 8

what major artery make up the anterior brain blood supply

Answer 8

internal carotid

Question 9

which main arteries make up the posterior brain blood supply

Answer 9

vertebral arterieis

Question 10

what is the site of anastamoses in the brain called

Answer 10

cerebral arterial circle

Question 11

what branches off the vertebral arteries are important in the posterior system

Answer 11

• Anterior (ventral) spinal arteries
• Posterior inferior cerebellar arteries (PICA)
• Posterior (dorsal) spinal arteries

Question 12

vertebral arteries join to form what a at the midline

Answer 12

basilar artery (located on basilar part of the pons)

Question 13

what are the important branches off the basilar arterior for circulation

Answer 13

anterior inferior cerebellar arteries
internal auditory arteries
poutine arteries
supereical cerebrellar arteries

Question 14

what are the important arteries for blood supply to the cerebellum off of the vertebral and basilar artery

Answer 14

anterior inferior cerebellar a
posterior inferior cerebellar
superior cerebellar a

Question 15

Basilar artery branches terminally into what two arterries

Answer 15

posterior cerebral arteries

Question 16

what is the most rostral branch off the basillar artery that supplies the cerebellum

Answer 16

superior cerebellar a

Question 17

what are the two main arteries that supply the spinal corf

Answer 17

posterior spinal arteries (2)
anterior spinal a (1)

Question 18

true or false, the anterior spinal a branch off the basillar a

Answer 18

false, branch off the vertebral arteries

Question 19

true or false: the posterior spinal a branch off the bascillar a

Answer 19

false, it branches off the vertebral artery (or PICA)

Question 20

what are the two general ways the spinal cord gets blood supply

Answer 20

1) off radicular arteriore
2) off segmental medullary arteries

Question 21

where do radicular a arrise from

Answer 21

segmental spinal arteries (usually comin off a major verssel like the post intercostal)

Question 22

what do radicular a in the spinal cord supplu

Answer 22

supply spinal roots and rootlets

Question 23

true or false: radicular a of the spinal cord are only at some spinal levels,

Answer 23

false they are al every spinal level

Question 24

what are the vessels called that arise from segmental spinal aa and supply spinal roots and rootlets

Answer 24

radicular arteries

Question 25

what is the function of the segmental medullary a

Answer 25

reinforce anteior and posterior spinal arteries

Question 26

are segmental medullary aa at all or only some spinal levels

Answer 26

only at some spinal levbels

Question 27

what is the largest segmental medullary artery and where is it located

Answer 27

great segmental medullary artery =lower thoracic and upper lumbar region

Question 28

why is there the largest segmental medullary a located in the lower thoracic and upper lumbar region

Answer 28

because that provides blood supply to lumbosacral plexus (enlargement) which then innervates the nervous system for the whole lower limb

Question 29

most of the supply to the spinal cord is done by what vessel

Answer 29

anterior spinal a

Question 30

explain the perfusion area of the anterior spinal a

Answer 30

supplies most of the spinal cord (anterior and lateral horns as well as their columns)

Question 31

would there be sensory only, motor only or both deficits if there was a blockage of the anterior spinal a and why

Answer 31

both sensory and motor since it is supplying most of the spinal cord (anterior and lateral horns)

Question 32

would there be sensory only, motor only or both deficits if there was a blockage of the posterioe spinal a and why

Answer 32

sensory only (since posterior only supplies the dorsal horns and columns)

Question 33

true or false: there is 1 main longitunial vein that drains blood from the spinal cord

Answer 33

false thre is two

Question 34

what is are the 2 main drainage systems for blood in the spinal cord

Answer 34

anterior spinal vein posterior spinal vein

Question 35

where do the longitudinal veins of the spinal cord drain

Answer 35

into the internal vertebral plexus

Question 36

where is the internal vertebral plexus located

Answer 36

in the adipose filled space (in epidural space) surrounding meningeal layers of the spinal cord

Question 37

where does the internal vertebral plexus drai

Answer 37

into major systemic veins (ex: inf vena cavam azygous veins) via small segmentally aranged vesseks

Question 38

internal carotid arteries continue as what (after giving some branches)

Answer 38

middle cerebral artery

Question 39

explain the passage of the internal carotid a

Answer 39

through transverse foramina, up through carotid canal and makes an S shape through cavervous sinus

Question 40

what are some branches off the internal carotid a (before it becomes middle cerebral)

Answer 40

opthalamic anterior choroidal anterior cerebral aa lenticulostriate aa

Question 41

after what 3 branches does the internal carotid a continue as middle cerebral

Answer 41

ophthalmic arteries anterior choroidal aa anterior cerebral aa

Question 42

what is a deep branch off the internal cartoid

Answer 42

lenticulostriate artieies

Question 43

true or false: the ophthalmic aa branch off the middle cerebral a

Answer 43

false, off the internal carotid

Question 44

the anterior cerebral aa branch off what vessel

Answer 44

internal carotid aa

Question 45

where do the anterior cerebral artieries go after branching off internal carotid

Answer 45

enter the median longitudinal fissure

Question 46

what deep branches off the anterior cerebral arteries go to subcortical structures

Answer 46

medial striate arteries

Question 47

the lenticulate arteries branch off what vessel

Answer 47

middle cerebral arties

Question 48

anterior choroidal artery supplies mostly which ventricle

Answer 48

lateral

Question 49

true or false, the anterior and posterior blood systems never meet in the brain

Answer 49

false, they do, cerebral arterior circle (circle of willis(

Question 50

what is the reason that the anteior and posterior blood systems anastamose

Answer 50

compensate for slow, chronic, changes in blood flow balance blood pressure between left and right halvs

Question 51

what are the two communicating arteries of the cerebral arterial circle

Answer 51

anterior communicating posterior communicating

Question 52

how many anterior communicating aa do we have

Answer 52

1

Question 53

how many posterior communicating aa do we have

Answer 53

2

Question 54

the anterior communicating a connects what

Answer 54

the left and right anterior cerebral arteries

Question 55

the posterior communicating a connects what

Answer 55

internal carotid a with posterior cerebral a

Question 56

which of these vessels is not part of the cerebral arterial circle: internal carotid postreior communicating meiddle cerebral anterior cerebral

Answer 56

middle cerebral

Question 57

true or false: the middle cerebral artery is part of the circle of willis

Answer 57

false it is not

Question 58

what vssels make up the circle of willis

Answer 58

left and right internal carotod left and right anterior cerebral left and right posterior cerebral left and right posterior communicating anterior communicating

Question 59

which structures sit in the middle of the circle of willis

Answer 59

optic chiasm (and optic nevbres) pituitary gland mamalary bodies

Question 60

what are the 3 main arteries that provide cortical perfusion

Answer 60

anterior cereal posterior cerebral middle cerebral

Question 61

explain cortical perfusion area of the anterior cerebral artery

Answer 61

medial aspect of frontal and parietal lobes 1-2 cm on lateral aspects of frontal lobe and parietal lobes deep branches also supply the caudate nucleus

Question 62

explain perfusion area of the middle cerebral a

Answer 62

vast majority of the lateral cortex (frontal aspects of superior and middle frontal gyri) frontal pole of temporal lobe insula lentiform nucleus (globus pallidus and putamen)

Question 63

true of false: the middle cerebral artery also supplies the insula and why

Answer 63

true because it passes thru lateral fissure

Question 64

explain perfusion of the posterior cerebral a

Answer 64

entire occipital lobe medial and inferior aspects of the temporal lobe (coveres the inferior, parahippocampal and occipitotemporal gyri) thalamus (deep branches)

Question 65

true or false: the entire occipital lobe is supplied by posterior cerebral a

Answer 65

true

Question 66

true or false: the entire temporal lobe is supplied by the posterior cerebral artery

Answer 66

false, only the medial and ingerior aspects (inf, parahippocampal and occipitotemporal)

Question 67

what are watershed regions

Answer 67

border zones between perfusion areas that are prone to ischemic stroke during hypoperfusion

Question 68

true or false: the borders between vessels are prone to ischemic stroke

Answer 68

true, they are watershed regions

Question 69

loss of blood supply to the cerebellum is associated with what

Answer 69

impaired motor coordination, stabilitiy and or balance

Question 70

what are the 3 vessels that provide cerebellar perfusions

Answer 70

superior cerebellar artery anterior inferior cerebellar a posterior inferior cerebllar a

Question 71

be able to locate the cerebellar perfusion area

Question 72

review tyhe brainstem perfusion patterns

Question 73

what are aneurysms

Answer 73

bulging/outpouching due to weakness or abnormality in arterior wall

Question 74

where do saccular brain aneurysms commonly occur

Answer 74

where brain vessels meet

Question 75

what is the issue with having aneurysms near brainstem

Answer 75

can pressure against cranial nerves

Question 76

what are some treatment options for aneurisms

Answer 76

clipping microcolis stents

Question 77

what is a storke

Answer 77

temporary or permanent loss of blood supply to a region of the brain

Question 78

what are the 2 types of stroke and quickly define

Answer 78

ischemic (blocked vessel ex: embolus) hermmoragic (ruptured or compromised vessel)

Question 79

true or false: ischemic strokes are due to ruptured or compromised vessels

Answer 79

false, hemmorgaic strokes are

Question 80

which of the following is part of the cerebral arterial circle middle cerebral artey superior spinal a anterior communicating a pontine as

Answer 80

anterior communicating a

Question 81

a patient is experiencing motor and somatosensory deficits in their left lower limb due to an ischemic stroke. which vessel supplying the right cerebral cortex is most likely affected

Answer 81

anterior cerebral atery

Question 82

whichh vessel supply the superior aspect of the cerebellum

Answer 82

superior cerebellar a

Question 83

which vessel supplies the lateral tips of the cerebellum from a posterior view

Answer 83

anterior inferior cerebellar a

Question 84

which vessel supples the posterir inn aspect of the cerebellum

Answer 84

posterior inferior cerebellar a

Question 85

which vessel supples the peduncles of the cerebellum

Answer 85

anterior inferior cerebellar a

Question 86

where does the superior cerebellar a branch from

Answer 86

basilar

Question 87

where does the posterior inferior cerebellar a branch from

Answer 87

vertebral

Question 88

where does the anterior inferior cerebellar a branch from

Answer 88

basilar

Question 89

what are the 2 vessels that supply the midbrain

Answer 89

posterior cerebral (majority) superior cerebellar (dorsal)

Question 90

what are the 3 vessels that supply the pons

Answer 90

bascillar (majority) anterior inferior cerebellar a (lateral) superior cerebellar (dorsal)

Question 91

what are the 3 vessels that supply the rostral medulla

Answer 91

anterior spinal (medial) vertebral (middle) posterior inferior cerebellar a (lateral and inferior)

Question 92

what are the 3 vessels that supply the. caudal medulla

Answer 92

anterior spinal (medial) vertebral a (middle) posterior spinal a

Question 93

what is the only difference in blood supply to rostral medulla vs caudal medulla

Answer 93

rostral = PICA caudal = posterior spinal