Transcript Neuroscience - Chiropractor Manhattan | Chiropractor New

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Neuroscience
Blood Supply of the Central Nervous System
Dr. Michael P. Gillespie
Blood Supply To the CNS
 The central nervous system is one of the most metabolically
active systems in the body.
 A brief interruption of blood flow can result in serious
neurological disturbances.
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Dr. Michael P. Gillespie
Level of Blood Flow
 The normal blood flow to the brain is about 50 mL/100g of
brain tissue/min.
 Ischemic penumbra is a blood flow of 25 mL/100g of brain
tissue/min. This level is dangerously low and can lead to loss
of brain cells.
 A blood flow of 8 mL/100g of brain tissue/min leads to an
almost complete loss of functional neurons.
 Consciousness is lost within 10 seconds of cessation of blood
supply to the brain.
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Dr. Michael P. Gillespie
Arterial Supply of the Brain
 Internal Carotid Arteries
 Vertebral Arteries
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Dr. Michael P. Gillespie
Branches of the Internal Carotid
Arteries
 Opthalmic artery
 Posterior communicating artery
 Anterior choroidal artery
 Anterior cerebral artery
 Middle cerebral artery
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Dr. Michael P. Gillespie
Vertebro-Basilar Circulation
 The two vertebral arteries merge to form the basilar artery.
 This arterial system supplies the medulla, pons,
mesencephalon, and cerebellum.
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Dr. Michael P. Gillespie
Vertebral Artery Branches
Anterior spinal artery
Posterior inferior cerebellar artery
Posterior spinal artery
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Dr. Michael P. Gillespie
Basilar Artery Branches
 Anterior inferior cerebellar artery
 Labyrinthine (internal Auditory) artery
 Pontine arteries
 Superior cerebellar artery
 Posterior cerebral arteries
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Dr. Michael P. Gillespie
Cerebral Arterial Circle (Circle of
Willis)
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Dr. Michael P. Gillespie
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Dr. Michael P. Gillespie
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Dr. Michael P. Gillespie
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Dr. Michael P. Gillespie
Venous Drainage of the Brain
 Sinuses
 Cerebral veins
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Dr. Michael P. Gillespie
Sinuses
 Superior sagittal sinus
 Inferior sagittal sinus
 Transverse sinus
 Confluence of sinuses
 Cavernous sinuses
 Sphenoparietal sinuses
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Dr. Michael P. Gillespie
Cerebral Veins
 Superficial cerebral veins
 Deep cerebral veins
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Dr. Michael P. Gillespie
Venous Return
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Dr. Michael P. Gillespie
Spinal Cord Arteries
 Posterior spinal arteries
 Anterior spinal artery
 Spinal medullary and radicular arteries
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Dr. Michael P. Gillespie
Spinal Cord Veins
 Anteromedian spinal vein
 Anterolateral spinal veins
 Posteromedian spinal vein
 Posterolateral spinal veins
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Dr. Michael P. Gillespie
Stroke (Cerebrovascular accident CVA)
 Diseases involving the blood vessels that supply the brain can cause
stroke.
 Blockage of vessels (occlusive stroke).
 Emboli
 Thrombus
 Bleeding from vessels (hemorrhagic stroke).
 Aneurysm
 Atrial-Venous Malformation AVM
 A ruptured aneurysm can cause a hematoma (blood clot) to form.
 The hematoma occludes blood flow to adjacent tissue causing brain
ischemia.
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Dr. Michael P. Gillespie
Stroke continued…
 This can result in syncope.
 If the symptoms of ischemia last for less than 24 hours it is
referred to as a transient ischemic attack (TIA).
 TIAs are usually caused by emboli. They are sometimes
caused by atherosclerotic plaques.
 If the neurological deficits persist for at least 24 hours it is
referred to as a stroke.
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Dr. Michael P. Gillespie
Risk Factors
 Old age
 High blood pressure
 Previous stroke or TIA
 High cholesterol
 Tobacco smoking
 Atrial fibrillation
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Dr. Michael P. Gillespie
Rehabilitation
 Rehabilitation should start as quickly as possible.
 Joint R.O.M.
 Strength
 Re-learning functional tasks.
 Activities of daily living.
 Speech and language therapy.
 Lasts a few days to over a year.
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Dr. Michael P. Gillespie
Cerebral Vascular Syndromes
 The cerebral cortex is supplied by the following arteries:
 Anterior cerebral artery
 Middle cerebral artery
 Posterior cerebral artery
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Dr. Michael P. Gillespie
Anterior Cerebral Artery Syndrome
 Damages the precentral
gyrus which results in
contralateral paralysis
(hemiplegia) (mainly of the
leg).
 Occlusion of both anterior
cerebral arteries produces
bilateral paralysis.
 Occlusion of the post central
gyrus results in impaired
sensation (mainly in the leg).
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Dr. Michael P. Gillespie
Middle Cerebral Artery Syndrome
 Occlusion of this artery
results in contralateral
hemiplegia, predominantly
in the upper extremities
and face.
 If the left hemisphere is
involved, aphasia
(disturbances in speech)
may occur because the
speech centers are located
laterally in this
hemisphere.
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Dr. Michael P. Gillespie
Posterior Cerebral Artery Syndrome
 Occlusion of the posterior
cerebral artery results in
hemianopsia.
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Dr. Michael P. Gillespie
Hemianopsia
Left homonymous
hemianopsia
Both visual fields intact
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Dr. Michael P. Gillespie
Hemianopsia
Bitemporal
hemianopsia
Binasal hemianopsia
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Dr. Michael P. Gillespie
Midbrain Vascular Syndromes
 Weber’s Syndrome
 Claude’s Syndrome
 Parinaud’s Syndrome
 Benedikt’s Syndrome
 Superior Cerebellar Artery Syndrome
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Dr. Michael P. Gillespie
Weber’s Syndrome
 Also called medial midbrain syndrome
 Occlusion of branches of the posterior cerebral artery.
 Ipsilateral paresis of adduction and vertical gaze.
 Pupillary dilation (damage to occulomotor nerve on the side
of the lesion).
 Hemiparesis or Hemiplegia (more often) of the contralateral
face, arm, and leg.
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Dr. Michael P. Gillespie
Claude’s Syndrome
 A brainstem stroke
syndrome.
 Ipsilateral oculomotor paresis
(oculomotor nerve palsy).
 Contralateral ataxia and
tremor.
 Contralateral hemiparesis.
 Contralateral hemiplegia.
 Affects the lower face,
tongue and shoulder.
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Dr. Michael P. Gillespie
Parinaud’s Syndrome
 A midbrain syndrome.
 Also called gaze palsy
syndrome and sylvian
aqueduct syndrome.
 Impaired upward vertical
gaze.
 Loss of pupillary light reflex.
 Henri Parinaud is the father
of French ophthalmology.
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Dr. Michael P. Gillespie
Benedikt’s Syndrome
 A midbrain lesion.
 Oculomotor nerve paresis.
 Ataxia.
 Hemiparesis (more often) or hemiplegia of the contraleteral
face, arm, and leg.
 Similar to Weber’s Syndrome.
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Dr. Michael P. Gillespie
Superior Cerebellar Artery Syndrome
 Analgesia and thermoanesthesia on the ipsilateral side of the
face (trigeminal nerve damage).
 Ipsilateral Horner’s Syndrome.
 Contralateral loss of sensations of pain and temperature
(spinothalamic tract).
 Ipsilateral limb and gait ataxia.
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Dr. Michael P. Gillespie
Horner’s Syndrome
 Constriction of the
ipsilateral pupil (miosis).
 Drooping of the upper
eyelid (ptosis).
 Sinking in of the eyeball
(enophthalmos).
 Decreased sweating
(anhidrosis) on the side of
the face affected.
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Dr. Michael P. Gillespie
Pontine Vascular Syndromes
 Loss of blood supply to regions of the Pons.
 Upper motor neuron paralysis.
 Facial paralysis.
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Dr. Michael P. Gillespie
Incidence
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Dr. Michael P. Gillespie
Necrosis
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Dr. Michael P. Gillespie
Subdural Hematoma
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Dr. Michael P. Gillespie
Parenchymal Bleed with Hematoma
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