Stroke Syndromes

Overview

Major regions of stroke

Region	Area supplied	Function
MCA	Lateral frontal lobes, temporal lobes, lateral anterior parietal lobes	Upper body, language
ACA	Mesial and anterior frontal lobes, medial parietal lobes	Lower body, pelvic floor musculature, sensory integration
Ophthalmic artery	Eyes	Vision
PCA	Occipital lobes, posterior temporal lobes, posterior parietal lobes, midbrain, various cranial nerve ganglia (III, VII, X, XII)	Vision, balance, sensory integration, cranial nerve function
PICA	Posterior inferior cerebellum, posterior lateral medulla	Facial sensation, pain sensation from body, CN X

Vascular Territories

Anterior vs Posterior Circulation

Circulation	Description	Presentation
Anterior circulation	Likely thrombus from the carotid system. Most likely affects cerebral function	Aphasia, dysphasia, hemiparesis, amaurosis fugax, hemisensory loss, hemianopic visual loss
Posterior circulation	Likely thrombus from the vertebrobasilalr system. Most likely affects the cerebellar and brainstem function	Diplopia, vertigo, vomiting, dysphagia, dysarthria, hemianopic visual loss, hemisensory loss, transient global amnesia, loss of consciousness (rare)

Vascular territories and common presentation

Location	Presentation
Middle cerebral artery (50%)	Facial and upper extremity weakness/numbness, aphasia (left MCA), dysarthria, dysphagia, contralateral homonymous hemianopsia, hemineglect (right MCA)
Anterior cerebral artery	Lower extremity weakness/numbness, urinary incontinence, primitive reflexes, rigidity, gait apraxia
Posterior cerebral artery	Prosopagnosia, macular-sparing homonymous hemianopsia, alexia, visual hallucinations, sensory loss, CN III palsy, motor deficits
Internal carotid artery	Similar to MCA stroke, monocular blindness, amaurosis fugax if the ophthalmic artery is affected
Lacunar stroke	Pure motor or pure sensory, “clumsy hand””

Anterior circulation stroke

Syndrome	Motor/Sensory	Visual	Others
MCA	Upper body, facial droop	Eyes deviate towards the lesion, contralateral homonymous hemianopsia	Verbal deficits (receptive or expressive aphasia), verbal agnosia, confusion, apraxia, spatial deficits
ACA	Lower body, pelvic	N/A	Urinary incontinence, personality change

Posterior circulation stroke

Syndrome	Motor/Sensory	Visual	Others
PCA	N/A	Contralateral homonymous hemianopsia with macular sparing, visual agnosia, prosopagnosia	Visual hallucinations
Weber	Contralateral hemiparesis	Ipsilateral CN III palsy, Ipsilateral Horner’s syndrome	Contralateral gait disturbance (mild)
Benedikt	Contralateral hemiataxia (choreiform movements)	Ipsilateral CN III palsy, Ipsilateral Horner’s syndrome	Contralateral gait disturbance (severe)
Lateral medullary	Ipsilateral facial sensory loss, contralateral body loss of pain and temperature	Ipsilateral Horner’s syndrome	Vertigo, ataxia, dysarthria, dysphagia
Lacuna	Pure motor, pure sensory stroke (isolated focal signs)

Middle Cerebral Artery (MCA) Territory Stroke

The MCA is the most common artery involved in stroke. The MCA divides into a superior and inferior branch. It affects the upper body more than the lower body. If the stroke is on the left, can affect language, e.g. Broca’s and Wernicke’s aphasia

• Signs and symptoms
  • Contralateral lower facial paralysis
  • Contralateral body hemiplegia/sensory loss
  • Receptive or productive aphasia (dominant lesion)
  • Neglect (non-dominant lesion)
  • Verbal agnosia
  • Bilateral eye deviation towards the side of infarct (affects CN III but abduction by CN VI remains intact). May have contralateral homonymous hemianopsia (rare)

Anterior Cerebral Artery (ACA) Territory Stroke

ACA stroke affects the lower body more than the upper body

• Signs and symptoms
  • Contralateral body hemiplegia and sensory loss
  • Urinary incontinence (due to weakness of pelvic floor musculature)
  • Anosmia (olfactory bulb)
  • Personality change (frontal lobe, long-term symptom)
  • Abulia (unmotivated state)
  • Amnesia

Posterior Cerebral Artery (PCA) Territory Stroke

PCA strokes present with visual symptoms. There are rarely motor symptoms in a true PCA stroke.

• Signs and symptoms
  • Contralateral hemianopsia (primary visual cortex)
  • Visual hallucinations
  • Visual agnosia e.g. Prosopagnosia (difficulty recognising faces)
  • Occasionally neglect (non-dominant)
  • Transcortical aphasia (dominant)
  • Behavioral abnormalities and confusion (thalamic)
• Signs and symptoms of midbrain lesions
  • Contralateral hemiparesis
  • Ipsilateral CN III palsy
  • Contralateral ataxia (Ipsilateral CN 3 palsy)

Basilar Territory Stroke

• Contralateral signs and symptoms
  • Hemiparesis with or without UMN facial weakness
  • Hemisensory
  • Intranuclear ophthalmoplegia (MLF damage)
• Ipsilateral signs and symptoms
  • Horizontal gaze paralysis (PPRF damage)
  • Ataxia
  • LMN facial weakness (CN VII nucleus damage)
  • Facial sensory loss (CN V damage)
  • Nystagmus

Weber and Benedikt Syndrome

Weber and Benedikt syndrome is a mid-brain stroke caused by blockage of a penetrating branch of the PCA. It affects the substantia nigra, corticopontine tract, pyramidal tract, and CN III.

Syndrome	Structures affected
Weber syndrome	Substantia nigra, corticopontine tract, pyramidal tract, CN III
Benedikt syndrome	Substantia nigra, corticopontine tract, pyramidal tract, CN III, red nucleus

• Signs and symptoms
  • Parkinsonian like symptoms (affects substantia nigra)
  • Ipsilateral oculomotor palsy (down and out eyes)
  • Contralateral hemiplegia
  • Gait disturbance (in Benedikt syndrome due to involvement of the red nucleus)

Lateral Medullary Syndrome (PICA Territory Infarct)

Lateral medullary syndrome is a stroke to the posterolateral medulla due to blockage/haemorrhage of the posterior inferior cerebellar artery (PICA)

• Signs and symptoms
  • Pain and temperature loss in the contralateral body and ipsilateral face
  • Dysphagia (due to involvement of CN X)
  • Ipsilateral Horner’s syndrome (due to infarct of descending sympathetic tract)
  • Dizziness, ataxia and dysarthria

Lateral Pontine Syndrome

Lateral pontine syndrome is caused by infarction of the anterior inferior cerebellar artery. It affects the lateral spinothalamic tract, CN VII nucleus/lower motor neuron, CN VIII nucleus, cerebellar peduncle, and descending sympathetic tract

• Signs and symptoms
  • Pain and temperature loss in the contralateral body and ipsilateral face
  • Central hearing loss (due to involvement of CN VIII)
  • Nystagmus
  • Loss of balance
  • Gait ataxia
  • Ipsilateral Horner’s syndrome

Anterior Inferior Cerebellar Artery (AICA) Territory Stroke

• SIgns and symptoms
  • ipsilateral ataxia
  • Ipsilateral hearing loss (labyrinthine artery branch)
  • Vertigo

Posterior Inferior Cerebellar Artery (PICA) Territory Stroke

• Contralateral signs and symptoms
  • Hemisensory loss
• Ipsilateral signs and symptoms
  • Tongue deviation
  • Facial sensory loss
  • Horner’s syndrome (sympathetic damage)
  • Ataxia
• Bublar signs and symptoms
  • Dysarthria
  • Dysphagia
  • Nystagmus
  • Hoarsness