Ischemic StrokeBy Bhanu Prakash

definition

Acute cerebral focal defecit lasting for greater than 24hrs

classification

STROKE

Ischemic hemorrhagic

• Reduction of blood flow that lasts longer than several seconds• Blood flow

0 ml ------------- brain death<16ml/100gm/min ------------- infarction within an hour<20ml/100gm/min ------------- ischemia without infarction

Ischemic pathway

Transient ischemic attack(TIA)

complete recovery of symptoms in 24hr most TIA’s last 5-20 minutes

if >1hr usually small infarction on MRITIA’s predict future strokes30% TIA will have a stroke in 5yrs, 20% in 1 monthHigh risk TIA: ABCD

Age>60,BP > 140/90,Clinical weakness or speech,Duration >10min, diabetes

if all 5 factors 40% risk stroke in 7 days urgent workup

Lazarus effect, + emboli detection

TIA Syndromes

Amaurosis fugaxsudden onset painless vision loss, curtain over

one eye, brief 1-5minophthalmic artery emboli

Subclavian stealgives B/S ischemia, worse with arm exercise

Transient global amnesiareversible antegrade + retrograde memory loss,

repetitive questionsCrescendo TIA’s

cerebral ischemia increasing in frequency, severity and duration

Capsular warning syndrome: repeated weakness face, arm, leg

DDx TIA

Migraine, Seizure, SyncopeTumor, Subdural, SAHHypoglycemiaLabyrinthine dz

TIA rarely march across bodysuggests Sz, migraineinvoluntary movements more Szfortification/scintillating light more migraine

Embolic stroke

Cardio embolic Artery-to-artery

Atrial fibrillationMural thrombusMyocardial infarctionDilated cardiomyopathyValvular lesions

Mitral stenosisMechanical valveBacterial endocarditis

Paradoxical embolusPatent foramen ovaleAtrial septal defect

Atrial fibrillation Mural thrombus Myocardial infarction Dilated cardiomyopathy Valvular lesions

Mitral stenosisMechanical valveBacterial endocarditis

Paradoxical embolusPatent foramen ovaleAtrial septal defect

Cardio embolic

Artery-to-artery embolism

Carotid bifurcation

Aortic arch

Arterial dissection

Artery to artery embolism

Thrombotic stroke

Small vessel thrombosis (lacunar stroke)

Large vessel thrombosis

Uncommon causes

Hypercoagulable disordersVenous sinus thrombosisFibromuscular dysplasiaVasculitisCardiogenicDrugsEclampsiaMoya moya disease

Stroke syndromes

Anterior CirculationMCAACA

Posterior CirculationPCABasilarVertebral

Lacunar

Signs and symptoms of MCAO

Proximal MCAcontralateral hemiplegia, conjugate eye deviation,

hemisanesthesia,homonymous hemianopsia, aphasia or neglect

Upper MCAface + arm affected more than leg, Broca’s aphasia

Lower MCAleg> face + arm, Wernicke aphasia or behavioural

disturbance (nondominant hemisphere), homonymous hemianopia

Angular gyrusGerstmann’s syndrome: finger agnosia, acalculia, R-L

disorientation,agraphiaRight parietal

anosognosia, neglect, apraxia, impaired prosody, confusion/delirium

Hemineglect

ACA

ACA stroke

less common 3%weakness LE >UEabulia, akinetic mutism, emotional

disturbancetranscortical motor aphasiahead deviation toward lesionParatoniaAnt choroidal a. syndrome –ant limb int

capsulehemiparesis, hemisensory loss, hemianopia

Circle of willis

PCA syndromes

Weber SyndromeEponym: Weber SyndromeAnatomy: Midbrain: BaseVascular: Posterior cerebral artery:

Penetrating branches to midbrain

Side Manifestation comments

C Weakness- upper and lower extremity

Corticospinal tract

I Lateral gaze weakness

CN3

Symptoms and signs

PCA syndromes

Claude SyndromeEponym: Claude SyndromeAnatomy: Midbrain: TegmentumVascular: Posterior cerebral artery

Side Manifestation

c Ataxia- arm and leg

PCA syndromes

Thalamic pain syndromeEponym: Dejerine Roussy syndromeAnatomy: ThalamusVascular: Posterior cerebral artery:

Pentrating branches to thalamus

Side Manifestation

C Hemisensory loss – all modalities

C Hemibody pain

PCA syndromes

Alexia without agraphiaAnatomy:

Cerebral hemisphere: Left occipital region plus splenium of corpus collosum

Vascular: Posterior cerebral artery: Collosal branches

side manifestations comments

N Alexia Splenium of corpus

callosum

C Visual loss- homonymous hemianopia

Left occipital region

Signs and symptoms

PCA syndromes

Cortical blindnessEponym: Anton SyndromeAnatomy: Cerebral hemisphere: Bilateral

occipital lobesVascular: Posterior cerebral artery:

BilateralBasilar artery: Top of the basilar

Signs and symptoms

side manifestation

N Bilateral visual loss

C Unawareness of/ denial of blindness

PCA syndrome

Balint SyndromeEponym: Balint SyndromeAnatomy: Cerebral hemisphere: Bilateral

parietaloccipital lobesVascular: Posterior cerebral artery:

Bilateral

Side Manifestation

B Loss of voluntary but not reflex eye movements

B Optic ataxia poor visual motor coordination

B Asimultagnosia inability to understand visual objects

PCA syndromes

Posterior cerebral artery unilateral occipital

Anatomy: Cerebral hemisphere: Occipital and inferomedial temporal lobes.

Vascular: Posterior cerebral artery

Side Manifestation comments

C Visual loss – homonymous hemianopia

Optic pathway, calcrine cortex

Vertebral artery syndromes

Medial medullary syndromeEponym: Dejerine SyndromeAnatomy: Medulla: Medial medullaVascular:

Vertebral artery: Anteromedial artery Anterior spinal artery: Anteromedial artery

Basilar arterySIDE MANIFESTATIONS COMMENTS

C Weakness UL & LL Pyramidal tract

C Hemisensory loss _ vibration & proprioseption

Medial lemniscus

I Tongue weakness +/_ atrophy Cn 12 nucleus

CS AT MEDULLACS AT MEDULLA

WALLENBERG SYNDROME

Eponym: Wallenberg SyndromeAnatomy:LATERAL MEDULLAVascular: Vertebral artery

SIDE MANIFESTATION COMMENT

I SENSORY LOSS_FACE_TEMP PAIN C5 NUCLEUS

I ATAXIA RESTIFORM BODY CEREBELLUM

I NYSTAGMUS ,NAUSEA VOMITING, VERTIGO

VESTIBULAR

I HOARSENESS,DYSPHGIA NUCLEUS AMBIGOUS

I HORNERS SYNDROME DES SYMPAT

C HEMISENSORY LOSS PAIN AND TEMPERATURE

SPINO THALAMIC

Basilar artery occlusion

Locked in Syndrome Anatomy: Pons: Bilateral ventral

pons Vascular: Basilar artery

Side Manifestation Comment

B Weakness UL&LL B/L corticospinal

B Weakness face entire & dysarthria

B/L corticobulbar

B Lateral gaze weakness B/L fasiculus VI cn

Millard gublar syndrome

Anatomy: Pons: Basis pontis and fascicles of CN VI amd VII

VascularBasilar artery: Short circumferential

branchesBasilar artery: Paramedian branches

side Manifestation Comment

C Weakness UL&LL Pyramidal tract

I Lateral gaze weakness Cn VI nuc

I Weak face_ entire Cn VII nuc

Foville Syndrome

Anatomy: Pons: Unilateral lesion in the dorsal pontine tegmentum in the caudal third of the pons

Vascular: Basilar artery: Paramedian branches Basilar artery: Short circumferential

arteries

Side manifestations Comment

C Weakness UL&LL Corticospinal.t

I Weakness of face entire CN VII NUC

Lacunar strokes

Infarct from small penetrating arteries1. Pure motor –weakness face, arm and leg2. Pure sensory –paresthesias & numbness,

face, armand leg3. Sensory-Motor –weakness and sensory

loss4. Ataxia hemiparesis -weakness LE,

incoordinationipsilateral arm and leg5. Dysarthria-Clumsy hand syndrome dysarthria, dysphagia, dec fine motor hand

Lacunar strokes

Ddx of ishcemic stroke

Bell’s Palsy Todd’s Paralysis Hemorrhagic Stroke Subdural HematomaHypoglycemiaMetabolic conditions – fever, hyponatremia,

drugs, etc. Psychogenic Complex migraines Hypertensive crisis

Thank you