blood supply to the brain

what are the 2 main paired arteries supplying the brain?

- vertebral arteries

- internal carotid arteries

what happens to these arteries in the cranial vault?

form an anastomotic circle

what is the anastomotic circle called?

Circle of Willis

where doe the internal carotid arteries originate from?

bifurcation of left and right common carotid arteries at C4

where do the internal carotid arteries travel before entering skull?

travel within carotid sheath

where do the internal carotid arteries enter cranium?

carotid canal of the temporal bone

where do the internal carotid arteries go once in the cranium?

pass through cavernous sinus

what happens distally to cavernous sinus?

each ICA gives rise to 4 branches

what are the 4 branches?

- ophthalmic artery

- posterior communicating artery

- anterior choroidal artery

- anterior cerebral artery

what does the ophthalmic artery supply?

structures of the orbit

what does the posterior communicating artery do?

anastomotic 'connecting vessel' in the Circle of Willis

what does the anterior choroidal artery supply?

structures in cerebrum responsible for motor control and vision

what does the anterior cerebral artery supply?

part of cerebrum

what are the non-branched portions of the internal carotid arteries now called?

the middle cerebral arteries

where do the middle cerebral arteries supply?

lateral portions of cerebrum

where do the right and left vertebral arteries arise from?

subclavian arteries

where do the right and left vertebral arteries travel before entering cranium?

through holes in cervical vertebrae called foramen transversarium

where do the right and left vertebral arteries enter the cranial cavity?

foramen magnum of occipital bone

what branches are given off the right and left vertebral arteries once in the cranium?

- meningeal branch

- anterior and posterior spinal arteries

- posterior inferior cerebellar artery

what happens after these branches?

the left and right vertebral arteries merge to form basilar artery

what are the branches of the basilar artery before the circle of willis?

- pontine arteries

- superior cerebellar arteries

what is the terminal branch of the basilar artery that forms the posterior of the circle of willis?

posterior cerebral arteries

what are the 3 main components of the circle of willis?

- anterior cerebral arteries

- internal carotid arteries

- posterior cerebral arteries

where do the anterior cerebral arteries arise from?

terminal branch of internal carotid arteries

what are the 'connecting vessels' of the circle of willis?

- anterior communicating artery

- posterior communicating arteries

what does the anterior communicating artery do?

connects the two anterior cerebral arteries

what do the posterior communicating arteries do?

connect internal carotid arteries to posterior cerebral arteries

what are the branches of the middle cerebral arteries?

lenticulostriate arteries

what do the lenticulostriate arteries supply?

basal ganglia and internal capsule