Download stroke

CVD:
STROKE
Septemius A. Pansacola RN,MD
ANATOMY OF
THE BRAIN
ANATOMIC DIVISION
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Two cerebral hemispheres
Brain stem
• Midbrain
• Pons
• Medulla

cerebellum
Lobes of the cerebral hemisphere
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Frontal lobe
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•
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•
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Planning and sequencing of movement
Voluntary eye movement
Emotional affect
Broca’s area
Parietal lobe
• Subserve motor control and cortical sensation
• Dominant: governs motor program
• Nondominant: governs spatial orientation
Lobes of the cerebral hemisphere

Temporal lobe
• Subserve olfaction
• Memory
• Certain components of auditory and
visual perception
• Wernicke’s area
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Occipital lobe
• Visual perception and involuntary eye
movement
Vessels supplying blood to the
brain

Anterior Circulation
• Anterior Cerebral Artery
• Middle Cerebral Artery
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Posterior Circulation
• Posterior Cerebral Artery
Anterior Circulation
anterior cerebral
artery
• extends upward and
forward from the
internal carotid artery
• supplies the frontal
lobes, the parts of the
brain that control logical
thought, personality,
and voluntary
movement,
• Stroke in the anterior
cerebral artery results
in opposite leg
weakness.
Anterior Circulation
Middle Cerebral Artery

largest branch of the
internal carotid.

supplies a portion:
• frontal lobe
• lateral surface of the
temporal and parietal
lobes
• includes the primary
motor and sensory areas
of the face, throat, hand
and arm and in the
dominant hemisphere, the
areas for speech.
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artery most often
occluded in stroke
lenticulostriate arteries
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Small, deep
penetrating
arteries which
branch from the
middle cerebral
artery
lacunar strokes
Posterior Circulation
Posterior cerebral artery

Originates in the
• basilar artery
• ipsilateral internal carotid
artery
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supply the temporal and
occipital lobes
Infarction:
• usually secondary to
embolism
• vertebral basilar system or
heart.

The most common finding
is occipital lobe infarction
leading to an opposite
visual field defect
Circle of Willis

Arterial
anastomosis of
vessels that
enables the entire
brain to reliably
vascularized
World Health Organization

neurological deficit of
cerebrovascular cause that persists
beyond 24 hours or is interrupted by
death within 24 hours'
stroke

blood supply to a part of your brain
is interrupted or severely reduced:
• oxygen and nutrients.

caused by
• thrombosis, embolism, or hemorrhage

Stroke is a medical emergency.
• Early treatment can also minimize
damage to your brain and potential
disability.
epidemiology

It is the third leading cause of death
and the leading cause of adult
disability in the United States and
industrialized European nations.
Risk factors
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advanced age
Hypertension
previous stroke or TIA (transient
ischaemic attack)
diabetes mellitus
high cholesterol
cigarette smoking
atrial fibrillation
Migraine with aura
thrombophilia
Stroke Warning Signs

Sudden weakness, paralysis, or numbness of the
face, arm and the leg on one or both sides of the
body

Loss of speech, or difficulty speaking or
understanding speech

Dimness or loss of vision, particularly in only one
eye

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Unexplained dizziness (especially when
associated with other neurologic symptoms),
unsteadiness, or sudden falls
Sudden severe headache and/or loss of
consciousness
Types of Stroke

Strokes may be classified into two
general types:
• ischemic
• hemorrhagic
Types of Stroke
Ischemic Stroke

80% of strokes are ischemic
• 50%: cerebral thrombosis

30% of strokes: Large-vessel thrombosis
• (e.g., carotid, middle cerebral, or basilar arteries)
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20% involve small, deeply penetrating arteries
• (e.g., lenticulostriate, basilar penetrating, medullary):
lacunar stroke.
• 30%: cerebral embolism
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most frequently: heart or from the cervical portion of
the carotid artery
more common in younger patients
develop rapidly
maximum deficit usually present within seconds to
minutes.
Hemorrhagic stroke

20% of all strokes
• intracerebral
hemorrhage
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
also called a
parenchymal
hemorrhage
The major risk factor:
hypertension
• Minute dilations at
small artery
bifurcation
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Occurs: basal
ganglia and
thalamus
Most signs and
symptoms
• compression of brain
structures and blood
Berry Aneurysm
• subarachnoid
hemorrhage

usually follows the
rupture of an
aneurysm or an
arteriovenous
malformation
Systemic hypoperfusion

reduction of blood flow to all parts of
the body.
• all parts of the brain may be affected
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most commonly due
• cardiac pump failure/ low cardiac output
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Cardiac arrest
Arrhythmias
pulmonary embolism
pericardial effusion or bleeding
Signs and symptoms
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brainstem: 12 cranial nerves
• altered smell, taste, hearing, or vision (total or partial)
• drooping of eyelid (ptosis) and weakness of ocular
muscles
• decreased reflexes: gag, swallow, pupil reactivity to light
• decreased sensation and muscle weakness of the face
• balance problems and nystagmus
• altered breathing and heart rate
• weakness in sternocleidomastoid muscle (SCM) with
inability to turn head to one side
• weakness in tongue (inability to protrude and/or move
from side to side)
Signs and symptoms
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cerebral cortex
• aphasia
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•
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Brocas area
Wernicke's area
apraxia (altered voluntary movements)
visual field defect
memory deficits
Hemineglect
disorganized thinking, confusion, hypersexual gestures
cerebellum
• trouble walking
• altered movement coordination
• vertigo and or disequilibrium
Diagnosis
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neurological examination
blood tests
CT scans
MRI scans
Doppler ultrasound
arteriography
CT vs. MRI
For diagnosing ischemic stroke in the emergency setting
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CT scans (without contrast enhancements)
• sensitivity= 16%
• specificity= 96%

MRI scan
• sensitivity= 83%
• specificity= 98%
For diagnosing hemorrhagic stroke in the emergency setting

CT scans (without contrast enhancements)
• sensitivity= 89%
• specificity= 100%
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MRI scan
• sensitivity= 81%
• specificity= 100%
Doppler ultrasound
Internal Carotid stenosis
Carotid endarterectomy
Angiography
Treatment
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Ischemic Stroke
• antiplatelet medication
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aspirin
Clopidogrel
Dipyridamole
anticoagulant medication warfarin
• Thrombolysis
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Tissue plasminogen activator
first 3 hours
• Mechanical Thrombectomy
• Hemorrhagic stroke must be ruled out with
medical imaging
Mechanical Thrombectomy
Treatment
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Hemorrhagic stroke
• Neurosurgical evaluation
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detect and treat the cause of the bleeding.
• Patients are monitored and their blood
pressure, blood sugar, and oxygenation
are kept at optimum levels.
Care and rehabilitation
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help the survivor:
• adapt to difficulties
• prevent secondary complications
• educate family members to play a supporting
role.
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rehabilitation team
• nursing staff, physiotherapy, occupational
therapy, speech and language therapy, and
usually a physician trained in rehabilitation
medicine