Transcript Arterial blood supply of the brain

Arterial Blood Supply
 Arterial blood supply of the brain
 Brain is supplied by pairs of internal carotid artery and
vetebral artery.
Internal Carotid Artery
 Internal carotid artery: branch off from common
carotid artery, enters brain from carotid canal, splits
into middle and anterior cerebral artery ,splits into the
terminal branches, it gives off:
Branches from ICA
 1). Hypophysial arteries: further splits into
 anterior hypophysial artery: supply hypothalamus. The anterior
hypophysial artery breaks into capillaries forming the hypophyseal
portal veins which convey hormones from hypothalamus into anterior
pituitary.
 posterior hypophysial artery: supply neural lobe of the pituitary
 2). Ophthalmic artery: supply eyes, paranasal sinuses and parts
of the nose
 3). Posterior communicating artery: runs backward to join the
posterior cerebral artery
 4). Anterior choroidal artery: supply choroid plexus of
temporal horn of lateral ventricles and other areas including
optic tract, uncus, hippocampus, lateral geniculate nucleus,
etc.
Occlusion of internal carotid artery
 1. ipsilateral blindness (ophthalmic A)
2. half vision of the contralateral eye (infarction of
optic nerve, lateral geniculate body supplied by
anterior choroidal A)
Terminal Branches
 Middle Cerebral Artery:
 bigger branch of the two terminal branches
 It branches off frontal, parietal, and temporal branches supplying
primary motor and premotor cortex, frontal eye field, primary
somatosensary area. Left middle cerebral artery supplies language
center.
 Occlusion of middle cerebral artery: paralysis of face, arm, aphasia
(language center)
 Anterior Cerebral Artery:
 meets together to form anterior communicating artery before they
join, gives off recurrent artery of Heubner, also called medial straite
artery, supplies corpus striatum.
 It then ascends along the longitudinal fissure then bends backward
around the genu of the corpus callosum. It branches into
pericallosal artery, along the upper surface of corpus callosum and
callosomarginal artery follows the cingulate sulcus, which has three
branches (anterior medial frontal, medial frontal medial, and
posterior medial frontal)
Anterior Cerebral A
 Occlusion of anterior cerebral artery
 contralateral paralysis and sensory deficits in the leg
and perineum, urinary incontinence. Often with
mental confusion.
Vertebrobasilar
system
 Vertebral artery, branch from the subclavian artery,
joins together to form the basilar artery. The latter
artery splits into posterior cerebral arteries.
 Branches off the vertebral artery
1. spinal artery: anterior spinal artery: one formed
by branches from each vertebral artery
2. posterior spinal artery: one on each side
3 . posterior inferior cerebellar artery (PICA)
largest branch off vertebral artery, supplies
cerebellar hemisphere, inferior vermis, etc.
Basilar artery
 Branches off basilar artery
 1. anterior inferior cerebellar artery (AICA)
supplies inferior surface of the cerebellum
2. labyrinthine artery supplies the membranous
labyrinth of the internal ear
3. Pontine arteries supply pons and pontine
tegmentum
4. superior cerebellar artery supplies pons,
superior cerebellar peduncle, and inferior
colliculus, etc.
Basilar artery
 Occlusion of basilar artery: basilar artery: coma, die
soon, loss control of respiration center labyrinthine
artery: deaf, vestibular dysfunction (vertigo, fall)
Posterior cerebral artery
 Posterior cerebral artery gives off
 1. Posterior medial central artery
 2. temporal artery: temporal lobe
 3. calcarine artery: supplies primary and association
cortex for vision
 4. parietooccipital branches: parietal and occipital lobes
 5. posterior choroidal artery: choroid plexus located at
central part of the lateral ventricle, third ventricle, etc.
Circle of Willis
 Consists:
 anterior communicating, anterior cerebral, internal carotid (short
segment), posterior communicating, and posterior cerebral arteries.
Normally not too much blood flow, could be served as alternative
route if one of the artery in occluded.
 Common site for aneurysms, terminal part of internal
carotid artery anterior communicating artery proximal of
middle cerebral artery
 Groups of arteries arise from the circle
 1. anteromedial group: branch from anterior cerebral and
communicating artery provides blood to hypothalamus
 2. anterolateral group: branch from middle cerebral artery
 3. posteromedial: branches from posterior cerebral and posterior
communicating arteries