Download Cerebrovascular diseases

Cerebrovascular diseases
Cerebrovascular diseases
• Vascular occlusive diseases (ischemic stroke)
• Intracerebral hemorrhage (hemorrhagic stroke)
Incidence of stroke
• 150-600 new cases per 100.000 population
per year
• 2-3rd leading cause of death
• 1st leading cause disability
Ischemic stroke
• Atherosclerosis of great cerebral vessels 20-40%
– Stenosis of vessels
– Atherothromboembolism
• Cardiac embolism
• Nonatherosclerotic vasculopaties and
15-30%
hematological abnormalities
• Unknown
10-20%
10-30%
Common sites of
atherosclerotic disease.
Normal blood flow
• 55 ml/100g per min - average
– 80-100 ml/100g per min for gray mater
– 25-30 ml/100g per min for white matter
• <20 ml/100g - ischemic stroke
Acute ischemia
• Transient Ischemic attack – neurological
deficit that resolves during 24 hours
• Reversible neurological deficit (minor
stroke) – deficit that resolves completely
during more then 24 hours
• Ischemic stroke – persistent neurological
deficit
Clinical presentations of
ischemic stroke
• Subacute begining (acute in cases of embosilsm)
• Consciousness is clear or short term lost of
consiousness. Not often unconsciousness
• Focal neurological deficit – main in clinical
picture
• Headaches, meningeal signs are not often
• History of TIAs, no history of hypertention
Treatment of acute ischemia
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1. Acute resuscitation
2. Reperfusion of the ischemic brain
3. Decreasing cerebral metabolic demands
4. Inhibition of the degradative ischemic
cascade
1. Acute resuscitation
• Respiration
– Intubation with ventilation for patients in coma
– Supplementary oxygen for other patient
• Arterial pressure
– Maintaining mild hypertension (if there is no evidence
of hemorrhage) or at least normal blood pressure
• Maintaining of adequate intravessel volume
• Controling heart output and arrhythmias
• Controlling of glucose level
2. Reperfusion of the ischemic
brain
• Thrombolytic therapy – recombinant
activator for tissue plasminogen
– In first 4-6 hours after onset
– If intracerebral hemorrhage is excluded with
CT
• Hypervolemic Hemodilution Therapy
• Anticoagulation ???
3. Decreasing cerebral metabolic
demands
• Hypothermia ???
• Barbiturates
Surgical treatment for acute ischemia
• Possible only in cases of stenosis of great
brain vessels (common carotid, internal
carotid, middle cerebral arteries) –
endarterectomia in first 2-3 hours.
Primary stroke prevention –
controlling of risk factors
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Hypertension (increases risk of stroke in4-5 times)
Smoking (1,5)
Diabetes. (2,5-4)
Lipids.
Cardiac Disease.
– Atrial fibrillation, (5)
– valvular heart disease, (4)
– myocardial infarction (5)
Secondary Stroke Prevention (After
Transient Ischemic Attack or
Ischemic Stroke)
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Aspirin 30-300 mg per day
Or Ticlopidine
Treatment or heart diseases
Surgical
Surgical prevention of ischemia
• EXTRACRANIAL-TO-INTRACRANIAL
CAROTID ARTERY BYPASS
• CAROTID ENDARTERECTOMY
CAROTID
ENDARTERECTOMY
• Indications
– Patients with TIAs with high grade stenosis of
CCA or ICA confirmed with ultrasound-dopler
and angiography
– Patients after stroke (strokes) that do not cause
severe diability
• angiograms of cervical carotid artery showing varied
appearance of critical stenosis of the internal carotid artery.
• A Smoothly tapered segmental narrowing.
• B Sharply demarcated stenosis.
endarterectomy
Causes of nontraumatic
intracranial hemorrhage
• Intracerebral hemorrhage
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Arterial hypertention (hemorrhagic stroke)
Bleeding from Arterio-venous malformation (AVM)
Rupture of aneurysm of cerebral vessel
Coagulopathies
vasculitis
• Subarachnoid hemorrhage
– Rupture of aneurysm of cerebral vessel
– Bleeding from Arterio-venous malformation (AVM)
Clinical signs of hemorrhagic
stroke due to hypertension
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Sudden and fast onset (seconds – minutes)
Unconsciousness (semicoma-coma)
Severe neurological deficit
Vegetative symptoms: high arterial
pressure; bradycardia, red face and cyanotic
limbs, sweating.
• Severe headache in contact patients
Diagnostic procedures
• Computed tomography (CT)
• Angiography
• EchoEG
Medial (thalamic) hematoma
Lobar hematoma
Brainstem (pontine) hemorrhage
Treatment
• Conservative only –
– for patients in clear consciousness or severe
coma (GCS 3-5)
– Medial hemorrhage (into basal ganglia)
– Hemorrhage into brainstem
• Surgical + conservative - for other patients
Conservative treatment
• Respiration control
– Intubation for comatose patients
– Supplementary oxygen
• Arterial pressure control
– Severe hypertention must be treated gently –
decrease pressure to mild hypertention during
several hours.
• Coagulative status control and correction
Surgical treatment
• Removal of intracerebral hematoma
• Ventricular draining in case of occlusive
hydrocephalus
Clinical presentation of SAH
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Sudden onset
Severe headache
Meningeal signs
Minimal focal neurological deficit
• More rarely depressed level of
consciousness and major neurological
deficit
Diagnostic procedures for SAH
• CT
• Lumbar puncture with CSF examination
– Blood in the CSF
– High pressure of CSF
– SAH and possible intracerebral hemorrhage
• Angiography – the main to reveal the cause
of SAH – aneurisms and arterio-venous
malformations
Aneurisms of cerebral arteries
• Localization
– Anterior cerebral a. and anterior communicans .
- 45%
– Internal carotid a. – 32%
– Middle cerebral a. – 20%
– Vertebrobasilar circulation – 4%
Aneurisms of cerebral arteries
• Saccular
• Others (traumatic, atherosclerotic, mycotic,
neoplastic, inflamatory)
• Saccular aneurisms – ovoid-shaped
outpouching of vessel wall, cased by
congenital insufficiency of elastic
component of vessel wall
SAH due to ruptured aneurism
• First rupture of aneurism – SAH only
• Repeated rupture in 20-50% of cases, most
of them during 3-20 days after first
• 50-85% mortality after repeated rupture,
• Intracerebral hemorrhage are often at
repeated rupture
• Often complicated with vasospasm and
consequent ischemical changes
Surgical treatment of aneurism
• Any aneurism should be excluded from
circulation as early as possible
– Putting clips on the neck of aneurism
– Endovascular embolisation of aneurism
• With coils
• With balloons
• Angiography
• 1 – in first day
• 2 – 3rd day –
angiospasm of middle
cerebral atery
• 3 – 4th day (after
treatment)
Internal
carotid
bifurcation
aneurysm.
Arteriovenous malformations
• heterogeneous group of vascular developmental
anomalies of the brain
• composed of a mass of abnormal arteries and
veins of different sizes.
• Functionally, they represent direct artery-to-vein
shunting with no intervening capillaries,
• angiographically are seen as early filling of veins.
Schematic drawing of AVM
Clinical presentations of AVMs
• Intracranial hemorrhage
– Intraparenchymal
– Subarachnoid
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Seizures
headache,
progressive neurological deficit,
cardiac failure.
Diagnosis
• Angiography
• MRI
Angiography
MRI – AVM in occipital lobe
Treatment of AVMs
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Observation
Surgical excision
Endovascular embolization
Radiosurgery
– Hamma-knife
– Linear proton accelerator
Hamma-knife