neurovasculature Flashcards
two main divisions
carotid and vertebrobasilar
major arteries coming from the heart
ASVCCECIC
-aorta, subclavian, vertebral, common carotid, external carotid and internal carotid
aorta artery
ascends from the left ventricle of the heart
subclavian artery
arises from aorta
vertebral artery
arises from the aorta and subclavian arteries
-branches off subclavian
common carotid artery
arises from the aorta and subclavian arteries
-branches off subclavian (right) and aorta (left)
external carotid artery
formed from common carotid
-blood to face and ear
internal carotid
formed from common carotid
-blood to brain, eyes, etc
what are the 2 major arteries coming from the heart to supply the internal nervous system
2 vertebral and 2 internal carotid arteries
-around 20% from vertebral
-around 80% from carotid
vertebral-basilar blood supply
from the vertebral arteries
-comprised of PICA, AICA, SICA, posterior cerebral arteries, and pontine arteries
posterior inferior cerebellar arteries (PICA)
supplies areas of the cerebellum, medulla, and choroid plexus of the 4th ventricle
anterior inferior cerebellar arteries (AICA)
supplies inferior portion of cerebellum, including the flocculus
superior cerebellar arteries (SiCA)
supplies superior cerebellum, much of the caudal midbrain and rostral pons
posterior cerebral arteries
supplies caudal diencephalon, medial occipital lobe and inferior temporal lobe
-midbrain level
pontine arteries
around to back of pons and anterior inferior cerebellar to cochlear nucleus
-penetrating arteries supply SOC
carotid blood supply
enters at base of brain
-comprised of anterior cerebral arteries, middle cerebral arteries, posterior communicating arteries, anterior choroidal artery, internal carotid and external carotid
anterior cerebral arteries
connected by anterior communicating artery
-arteries to corpus callosum arise from here
middle cerebral arteries
lateral surface of cerebral hemispheres and the temporal pole of the brain
posterior communicating arteries
join the posterior cerebral arteries of the vertebral basilar blood supply
internal carotid arteries
begins at upper border of the thyroid cartilage and ascends to reach the base of the skull, enters at the carotid canal (lacerum)
external carotid arteries
arise opposite of the upper border of the thyroid cartilage, curved course, ascends upward and forward
how many cerebellar arteries are there? cerebral?
3 of each
-posterior inferior, anterior inferior and superior cerebellar
-anterior, middle and posterior cerebral
waterhsed area
where one artery ends and another one picks up
circle of willis
protective mechanism to establish effective anastomotic flow of blood over time
-communicating arteries are main part
what is the goal of the circle of willlis
equal pressure in carotids and posterior cerebral arteries and across anterior cerebral
what blood vessels supply the outer ear
number of arteries from external carotid
what blood vessels supply the middle ear
branches from external carotid
what blood vessels supply the inner ear
external carotid, internal carotid, and labyrinthine artery
evidence shows that around _____% of SNHL could be from vascular deficits
40%
signs of a stroke
BEFAST
-Balance, Eyes, Face, Arms, Speech, Time
vascular plasticity
reorganization of blood flow due to longstanding atherosclerotic disease
-gets blood from one side to the other side where is normally would not be flowing
plexus
large network of blood vessels
hemorrhage
large amounts of blood escapes into surrounding tissues without clotting
hematoma
small amounts of blood that escapes into surrounding tissue causing bruising
embolus
foreign body (blood clot) that travels within the body and can constrict blood flow
thrombus
a blood clot
-lesions attached to the inner vessel wall
-can block partially or fully
cerebrovascular disease and accidents
most common cause of neurological deficits
-without blood flow to brain they cannot function and do their job
infarct
necrotic region of tissue
-dying tissue
stroke
abrupt incidence of vascular insufficiency
-losing blood to some area of their brain
ischemic strokes
loss of blood supply due to mechanical blockage
-transient : minutes to hours
aneurysms
localized dilation of a blood vessel where the wall is weak and can rupture
-can be corrected surgically if detected while small
anteriovenous malformations
arteries and veins tangle together and blood is shunted from arteries to the veins
-caused during development
blood brain barrier
tight junctions of the endothelial cells that line the capillaries in the CNS
-lipid soluble substances and glucose can cross
blood CSF barrier
macromolecules can reach the choroid plexus but the capillaries do not come in direct contact with CSF so there is a barrier
arachnoid barrier layer
arachnoid cells tightly zipped together with tight junctions to stop diffusion between the subarachnoid space and extracellular fluids of the dura mater
CSF brain interface
CSF bathes the brain and there are not cells with tight junctions so macromolecules move freely
where does the labyrinth artery branch off of
the vertebral-basilar artery
-could be the AICA or basilar artery
