Neuro: Ch. 6 Blood Supply Of The Brain

Front 1

autoregulation

Back 1

the control of blood flow by cerebal BV vasoconstrinction in response to increased blood pressure- this increases the resistance to blood flow

Front 2

chemoreception

Back 2

neurons, astrocytes and cerebral BV collaborate to respond to increased neural activity. they react to metabolites such as CO or glutamate to regulate blood flow in the brain

Front 3

autonomic innervation

Back 3

plays a minor role in regulating blood flow in the brain. helps system to adapt to stress and manage extremes of auto regulation range

Front 4

What are the 2 arterial sources in the brain?

Back 4

internal carotid= 80%
vertebral=20%

Front 5

What does the internal carotid artery supply and what are it's main branches?

Back 5

-supplies the telenchephlon and diencephlon
-anterior cerebral, anterior communication, middle cerebral, opthalmic, anterior choroidal & posterior commuicating arteries

Front 6

anterior cerebral artery supply & ischemic effects

Back 6

-supplies medial frontal and parietal lobes, corpus callosum
-Ischemia - contralateral motor and somatosensory deficits (> in legs)

Front 7

anterior communicating artery

Back 7

Join right and left anterior cerebral arteries

Front 8

middle cerebral artery supply & ischemic effects

Back 8

-lateral cerebral hemispheres (most pre/post central gyri)
-Ischemia - major motor and somatosensory deficits with ischemia, also language deficits if in dominant hemisphere

Front 9

ophthalmic artery supply & ischemic effects

Back 9

-orbital contents
-Ischemia - Vision loss

Front 10

anterior choroidal artery supply & ischemic effects

Back 10

-supplies choroid plexus (lateral ventricles), optic tract, internal capsule, thalamus
-Ischemia contralateral motor and somatosensory deficits as well as vision problems

Front 11

posterior communicating artery

Back 11

connects to posterior cerebral artery

Front 12

lenticulostriate / lateral striate arteries

Back 12

-Small branches of the middle cerebral artery supply deep structures of the diencephalon and telencephalon

Front 13

perforating branches

Back 13

-Smallest branches of the middle cerebral artery supply deep structures of the diencephalon and telencephalon, they are unnamed
-frequent area for stroke –-> disproportionate deficits due to thalamic connections (Internal capsule)

Front 14

Vertebral arteries

Back 14

-Pass through foramen magnum and join together to form basilar artery
-Supplies most of brainstem and cerebellum, as well as parts of diencephalon, occipital and temporal lobes
-Also blood supply to spinal cord

Front 15

What are the branches of the vertebral arteries?

Back 15

-Posterior spinal arteries (paired), supply blood for the posterior 1/3 of that half of cord
-Anterior spinal artery (unpaired), supply blood for the anterior 2/3 of cord
-Posterior inferior cerebellar artery (PICA) supply blood for the inferior cerebellar surface, 4th ventricle choroid plexus, and lateral medulla
-All 3 give off perforating branches to brainstem structures

Front 16

What comes off the Basilar artery?

Back 16

-2 branches
-Anterior inferior cerebral artery
-Postrior inferior cerebral artery
-posterior cerebral artery
-pontine
-labrinthine (sometimes, sometimes off AICA)

Front 17

Anterior inferior cerebellar artery

Back 17

(AICA), which supplies the anteriorinferrior cerebellum and caudal pons

Front 18

Posterior inferior cerebellar artery

Back 18

(PICA), supplies the inferior cerebellar surface, 4th ventricle choroid plexus, and lateral medulla

Front 19

Posterior cerebral artery supplies what and effects of ischemia

Back 19

-inferomedial occipital / temporal lobes and posterior choroid of 3rd ventricle
Ischemia - visual field losses

Front 20

pontine arteries

Back 20

– smaller branches of basilar artery supplies remainder of pons

Front 21

Labyrinthine / internal auditory artery supplies what and effects of ischemia

Back 21

– supplies inner ear
-Ischemia - results in vertigo and deafness (ipsilateral)

Front 22

Cerebral arterial circle

Back 22

-aka circle of willis
-interconnects internal carotid and basilar systems
-anterior communicating artery joins contralateral anterior cerbral arteries
-posterior communicating joins internal carotid to ipsilateral posterior cerebral arteries

Front 23

What are the 2 types of CVAs?

Back 23

ischemic and hemorrhagic strokes

Front 24

ischemic stroke

Back 24

caused by:Altered blood pressure
Arterial disease
Blockage

Front 25

hemorrhagic stroke

Back 25

caused by spontaneous rupture of small blood vessels
Causes ischemia distal to the rupture

Front 26

transient ischemic attacks (TIAs)

Back 26

-an ischemic event that ends relatively quickly (mins-hrs); becomes a stroke after 24 hours
-usually due to minute emboli that partially block artery then are broken down
-results in little or no neurological deficits

Front 27

spinal cord ischemia

Back 27

motor or sensory deficients in extremities distal to lesion site

Front 28

Aneurysm

Back 28

- ballon like swelling of the arterial walls
-causes deficits as it compresses structures when the swelling increases in size
-rupture can result in massive hemorrhage in the subarachnoid space

Front 29

Arteriovenous malformations (AVMs)

Back 29

-congenital defects where large anastomoses (communicating holes) exist between arteries and veins
-Can steal blood from adjacent b/c of low resistance
-may hemorrhage

Front 30

Venous drainage of brain

Back 30

-Include cerebral veins, dural sinuses, emissary veins (through skull) and venous plexuses
-Principle route is through cerebral veins that empty into dural venous sinuses
-Flow to internal jugular veins and basilar venous plexus around base of brain

Front 31

What do emissary veins do?

Back 31

Emissary veins connect extracranial veins with dural sinuses. Play a minor role in drainage but are clinacally important as they may spread infection into cranial cavity

Front 32

Superficial cerebral veins

Back 32

- these are on the surface of the cerebral hemisphere
-Superior group – empties into superior sagittal sinus
-Inferior group – empties into transverse and cavernous sinuses

Front 33

deep cerebral veins

Back 33

-drain internal structures
-more consistant configuration
-empty into straight sinus
-Internal cerebral vein: major deep vein
forms next to the interventricular foramen bends posteriorly
-Great cerebral vein (Great Vein of Galen)
formed by fusion of 2 internal cerebral veins
Joins with inferior sagittal sinus to form straight sinus

Front 34

Superior cerebellar artery

Back 34

supplies the superoanterior cerebellum, caudal midbrain, and rostral pons