Cerebrovascular DiseaseCerebrovascular Disease

Section 1 General Section 1 General considerationconsideration

Cerebrovascular disease: any abnormality of the brain resulting from a pathologic process of the blood vessels.

Cerebrovascular accident or stroke may be defined as a sudden interruption of blood supply or hemorrhage into apart of the brain.

the third commonest cause of death

ClassificationClassification

Ischemic transient ischemic attack (TIA)

cerebral thrombosis

cerebral embolism cerebral infarction

lacunar infarct Hemorrhagic cerebral hemorrhage

subarachnoid hemorrhage (SAH)

Blood supply of brainBlood supply of brain 1. Internal carotid system

Branchiocephalic trunk→right common carotid artery

left common carotid artery

→internal carotid artery → carotid foramen → Ophthalmic artery Anterior choroidal artery Posterior communicating artery Anterior cerebral artery Middle cerebral artery

Supply eyes and anterior 3/5 of the brain: frontal, parietal, part of temporal lobe, basal ganglia.

Blood supply of brainBlood supply of brain2. Vertebral-basilar systemSubclavian artery → vertebral artery → C6-C1

transverse foramen → great occipital foramen → basilar artery

posterior spinal arteries, anterior spinal artery posterior inferior cerebellar artery auditory artery posterior cerebral arteries

supply cerebellum, brain stem, posterior 2/5 of brain (occipital, part of tempral lobe)

3. Circle of WillisBlood supply of brainBlood supply of brain

This forms a unique anastomotic system at the base of the brain between the internal carotid and vertebral-basilar systems.

internal carotid arteries two anterior cerebral arteries anteriorcommunicating arterytwo posterior cerebral arteriestwo posterior communicating arteries

Blood supply of brainBlood supply of brain

Age, family history, raceHypertensionHeart diseaseDiabetesHyperlipemiaSmoking, excessive drinkingObesity, diet, contraceptive drugs

Risk factors of CVDRisk factors of CVD

Section 2 TIASection 2 TIA

A transient ischemic attack is a focal disturbance of the cerebral circulation, frequently repetitive, resulting in a period of impaired function lasting for a short period (anything from a few minutes to twenty-four hours). Attacks can occur in the carotid and/or vertebral artery territories.

Etiology Etiology

Micro embolismSpasm of cerebral blood vesselHemodynamic changeCompression of vertebral artery, steal

syndrome

Clinical featureClinical feature

1. 50-70, M>F

characteristics: Abrupt onset Transient Complete recovery Repetitive

2. Transient carotid ischemic attacks(1)Common symptoms: Weakness of the contralateral arm and/or leg.(2) Characteristic symptoms: Transient loss of vision in the eye contralateral to the

paresis (amaurosis fugax). Horner sign(3) Symptoms may present: Dysphasia Paraesthesia or numbness in the contralateral limbs. hemianopia

Clinical featureClinical feature

3. Transient vertebral –basilar ischemic attack

(1) Common symptoms Vertigo, nausea, vomiting

(2) Characteristic symptoms: Drop attack Transient global amnesia, TGA Cortical blindness Crossed paralysis or sensory disturbance

Clinical featureClinical feature

(3) Symptoms may present:Dysphagia, dysarthriaAtaxiaDisturbance of consciousnessdiplopia

Clinical featureClinical feature

Diagnosis Diagnosis

clinical features No signs between attack

Differential diagnosisDifferential diagnosis

Partial epilepsyMeniere disease

Treatment Treatment 1. Etiologic therapy Blood pressure, sugar, lipid Carotid endarterectomy, anastomosis of extra-

intra cranial vessels

2. Prophylactic treatment Anti-platelet aggregation drugs:

Aspirin 50-300mg Qd Po

Ticlopidine 250mg Qd Po

2. Prophylactic treatment Anticoagulants: heparin Chinese herbs

Chuanxiong rhizome, Red sage root, Saf flower Others: vessodilator, volume expensor (Dextran-

40)

3. Brain protective agents Calcium antagonist: nimodipine 20-40mg tid po

flunarizine (Sibelium) 5mg Qn po

Treatment Treatment

Prognosis Prognosis

1/3 → repetitive attack1/3 → remission1/3 → cerebral infarction

Section 3 Cerebral ThrombosisSection 3 Cerebral Thrombosis

infarction of an area of the brain secondary to arterial occlusion by thrombosis of a major vessel with insufficient collateral circulation.

Etiology Etiology atherosclerosis Arteritis: such as leptospirosis, rheumatic

feverrare cause:

congenital vascular malformation, polycythemia

blood hypercoagulability

Pathology Pathology

Vessel: carotid > middle > posterior > anterior > vertebral-basilar

Super-early stage: 1-6 hourNecrosis → cyst White infarct Red infarct: hemorrhagic infarct

Pathophysiology Pathophysiology

Neurons are sensitive to ischemiaCentral necrosisIschemic penumbraSuper early stage: < 6 hours

Clinical featureClinical feature

onset is rapid usually occur in the rest and sleep premonitory symptoms such as weakness of

a limb, transient ischemic attack The headache, vomit, and loss of

consciousness may be absent or slight. Focal signs develop in several days

Clinical typeClinical type

Complete strokeProgressive strokeReversible ischemic neurological deficit,

RIND)

Clinical syndromeClinical syndrome

1. Internal carotid arteryMay have no signs (if the collateral supply,

from the other side, is good )amaurosis fugax, uniocular blindnessHorner's syndrome may present in the side of

the occlusion. contralateral hemiplegia and hemianesthesia.

2. Middle cerebral artery contralateral hemiplegia, hemianesthesia,

hemianopiaaphasia (if the dominant hemisphere is

affected)Disturbance of body image (non-dominant

hemisphere)

Clinical syndromeClinical syndrome

3. Anterior cerebral artery contralateral hemiplegia, the leg frequently

being more affected than the arm. paracentral lobule: regulation of sphincter

function, retention or incontinencemental symptoms: apathy, euphoria

Clinical syndromeClinical syndrome

4. Posterior cerebral arterycontralateral hemianopia or quadrantanopia thalamic syndrome: contralateral hemianesthesia,

thalamic pain, ataxia, tremor, athetosis

Clinical syndromeClinical syndrome

5. Vertebro-basilar artery

(1) Main trunknausea, vomiting, tetraplegia, coma, death

(2) Weber syndromeUnilateral lesion of midbrainIpsilateral oculomotor nerve paralysis, contra

lateral hemiplegia

Clinical syndromeClinical syndrome

(3) locked-in syndromeBilateral infarction in the basis pontisTetraplegia, can not speak, can not swallow Conscious Can only respond by vertical gaze and

blinking

Clinical syndromeClinical syndrome

6. posterior inferior cerebellar artery Wallenberg's syndrome, Lateral medullary

syndromeVertigo, vomiting, nystagmusCrossed sensory disturbanceIpsilateral Horner sign Dysphagia, dysarthriaIpsilateral ataxia

Clinical syndromeClinical syndrome

Investigation Investigation 1. CT

Low density focus after 24-48 hours

2. MRI Investigation Investigation

A right carotid artery occlusion, low signal of T1, and high signal of T2 weighted image.

3. Lumbar punctureNormal.Large infarct: pressure ↑Hemorrhagic infarction: RBC

4. DSA

5. TCD

Investigation Investigation

Diagnosis Diagnosis

after middle or old age.rapid onset focal cerebral symptomspremonitory symptomsoccurs in rest or sleepCT/MRI find cerebral infarction focus

Differential diagnosisDifferential diagnosis

Cerebral hemorrhageCerebral embolismIntracranial tumor

Treatment Treatment 1. Principle2. Fibrinolytic therapy of super-early stage Within 6 hours Urokinase, rt-PA3. Anticoagulant Heparin, low molecular heparin4. Brain protect Calcium antagonist: nimodipine, flunarizine Mannitol Hypothermia

5. Fibrinogen degradationDefibrase, Batroxobin

6. Anti platelet aggregationAspirin, Ticlopidine

7. Others? Vessel dilator? Metabolic activator

Treatment Treatment

8. Surgical treatmentReduce intracranial pressure9. General managementReduce intracranial pressure: mannitol 10. Stroke unit11. Rehabilitation 12. Prophylactic treatmentAspirin, Ticlopidine

Treatment Treatment

Lacunar infarctLacunar infarct

Pathology Pathology

3-4mm, <15-20mmSmall liquid cavity Basal ganglia, thalamus, brain stemSmall artery: 100-200μmAtherosclerosis

Clinical featureClinical feature

40-60 years of age Always combined with hypertensionLacunar syndrome: 1. Pure motor hemiparesis 2. Pure sensory stroke 3. Ataxic-hemiparesis 4. Dysarthric-clumsy hand syndrome 5. Sensorimotor stroke 6. Lacunar state

Cerebral embolismCerebral embolism

Occlusion of a major cerebral artery by an embolus, with resultant infarction of part of the brain.

Etiology Etiology

Cardiac cause: Atrial fibrillation, rheumatic valve disease,

endocarditis, atrial myxoma, myocardial infarction

Non-cardiac: Atherosclerosis plaque, pus embolus, fat

embolus, tumor embolusEmbolus of unknown origin

Clinical featureClinical feature

Left middle cerebral arteryabrupt onset, maximum disability occurring

at onceIn some cases, there is rapid improvement The primary disease, such as rheumatic

heart disease

Treatment Treatment

CerebrovasodilatorsAnticoagulant therapyTreatment of primary disease