Circulation of the CNS Flashcards
Which two vascular systems provide input to the circle of willis?
the vertebrobasilar system and the internal carotid
What is the internal carotid a branch of?
the common carotid
What is the vertebral artery a branch of?
subclavian
Where does the vertebral artery travel?
ascends through transverse foramina and enters the skull through the foramen magnum
What is the basilar artery?
the two vertebral arteries united
What are the three main branches of the circle of willis?
the anterior, middle and posterior cerebral arteries
What does the anterior communicating artery join?
the anterior cerebral arteries
What does the posterior communicating artery join?
the posterior cerebral artery to the internal carotid
What is the course of the anterior cerebral artery?
branches off the internal carotid and travels through the longitudinal fissure over the top of the corpus callosum
What area of the cortex is supplied by the anterior cerebral artery?
the medial surface of the frontal and parietal lobes, including the medial part of the primary motor cortex and the primary somatosensory cortex (lower limb areas)
What would be the predicted effect of a stroke in the anterior cerebral artery?
contralateral hemi sensory loss and contralateral hemiparesis in the lower limb
What is the course of the middle cerebral artery?
branches off the internal carotid and projects laterally through the lateral fissure
What area of the cortex is supplied by the middle cerebral artery?
the lateral surface of the frontal, parietal, temporal and occipital lobes including the primary motor and primary somatosensory cortex (except lower limb)
If a stroke causes a language deficit which artery is probably involved?
the middle cerebral artery
What is the course of the posterior cerebral artery?
terminal branch of the basilar artery at the pontomedullary junction and then travels back towards the occipital lobes
What area of the cortex is supplied by the posterior cerebral artery?
the medial and inferior surfaces of the temporal and occipital lobes
If a stroke causes loss of contralateral visual field which artery is probably involved?
the posterior cerebral artery
Where do the anterior perforating branches come off and what do they supply?
branch off the anterior communicating artery and supply the optic chiasm and hypothalamus
Where do the posterior perforating branches come off and what do they supply?
branch off the posterior cerebral arteries and supply the ventral midbrain and the posterior part of the hypothalamus
Where do the lenticulostriate arteries branch off and what do they supply?
branch of the middle cerebral artery and supply the basal ganglia and internal capsule
Where do the pontine branches come off and what do they supply?
branch off the basilar artery and supply the pons
What is the ophthalmic artery a branch of and what does it supply?
branch of the internal carotid and supplies the eye, top of nasal cavity and front of scalp
What is the anterior choroidal artery a branch of and what does it supply?
branch of the internal carotid and supplies the optic tract and hippocampus as it follows the curve of the lateral ventricles
What are the branches of the vertebrobasilar system?
anterior spinal artery (vertebral), posterior inferior cerebellar artery (vertebral), anterior inferior cerebellar artery (basilar), superior cerebellar artery (basilar)
What is the blood supply to the cerebellum?
posterior inferior cerebellar artery, anterior inferior cerebellar artery, superior cerebellar artery
What is the blood supply to the midbrain?
the posterior cerebral artery and the superior cerebellar artery
What is the blood supply to the pons?
pontine branches of the basilar artery
what is the blood supply to the medulla?
anterior spinal artery medially, vertebral artery to the olives and the posterior inferior cerebellar artery posterolaterally
What is the functional outcome of a CVA in the anterior spinal artery?
loss of function of the hypoglossal nucleus results in ipsilateral atrophy of tongue muscles, damage to medial lemniscus causes contralateral hemisensory loss, damage to pyramids results in contralateral hemiparesis
What is the blood supply to the spinal cord?
anterior spinal artery ventrally and the posterior spinal arteries posterolaterally
