What are the clinical symptoms of cerebral artery stenosis?

Clinical Symptoms of Cerebral Artery Stenosis

Cerebral artery stenosis typically presents with focal neurological deficits that correspond to the territory supplied by the affected artery, including weakness, sensory disturbances, visual changes, and speech difficulties depending on the location of the stenosis. 1, 2

Common Symptoms by Arterial Territory

Internal Carotid/Middle Cerebral Artery Stenosis

• Right-sided stenosis symptoms:

  • Left-sided weakness
  • Left-sided paresthesia or sensory loss
  • Left-sided neglect
  • Abnormal visual-spatial ability
  • Monocular blindness affecting the right eye (amaurosis fugax)
  • Right homonymous hemianopsia (visual loss in right visual field)

• Left-sided stenosis symptoms:

  • Right-sided weakness
  • Right-sided paresthesia or sensory loss
  • Aphasia (language difficulties)
  • Monocular blindness affecting the left eye
  • Left homonymous hemianopsia 1, 2

Posterior Cerebral Artery Stenosis

• Visual symptoms (predominant presentation):
  • Difficulty seeing to one side
  • Homonymous visual field defects
  • Flashing lights
• Sensory symptoms:
  • Paresthesias (primarily in arm and hand)
  • May involve face and leg 3

Vertebrobasilar System Stenosis

• Ataxia
• Cranial nerve deficits
• Visual field loss
• Dizziness
• Imbalance
• Incoordination 1

Temporal Patterns of Symptoms

Transient Ischemic Attack (TIA)

• Acute neurological dysfunction referable to a single brain artery
• Traditionally defined as symptoms lasting <24 hours
• Some guidelines now define TIA as symptoms lasting <1 hour
• Typical duration is about 15 minutes 1, 2

Stroke

• Neurological deficits persisting >24 hours
• May range from mild to severe depending on:
  • Degree of stenosis
  • Plaque morphology and vulnerability
  • Efficacy of collateral circulation
  • Speed of occlusion development 1, 2

Special Clinical Presentations

Amaurosis Fugax (Transient Monocular Blindness)

• Temporary reduction of blood flow to one eye
• Most commonly caused by atherosclerosis of the ipsilateral internal carotid artery
• May be described as a "curtain" or "shade" coming down over the vision 1, 2

Cognitive and Higher Cortical Symptoms

• Memory difficulties
• Speech problems
• Hearing difficulties 2

Risk Factors and Progression

The risk of stroke in patients with symptomatic carotid stenosis is significant:

• Up to 13% in the first 90 days after TIA
• Up to 30% within 5 years
• 24% stroke rate after 18 months with 70% stenosis
• 22% stroke rate over 5 years with 50-69% stenosis 1

Diagnostic Pitfalls

1. Misattribution of symptoms: Not all neurological symptoms in patients with carotid stenosis are due to the stenosis. Up to 45% of ipsilateral strokes in patients with carotid stenosis may be attributable to lacunes or cardioembolism 2

2. Asymptomatic vs. symptomatic classification: Silent brain infarction on imaging or retinal emboli detected during screening are conventionally considered "asymptomatic" despite evidence of prior brain infarction 2

3. Non-focal symptoms: Transient global amnesia, acute confusion, syncope, isolated vertigo, non-rotational dizziness, bilateral weakness, and paresthesia are not clearly attributable to cerebral artery stenosis 1

4. Time window considerations: Symptoms beyond 6 months do not qualify as symptomatic in most guidelines 2

Understanding these symptom patterns is crucial for early recognition, appropriate diagnostic workup, and timely intervention to prevent stroke and reduce morbidity and mortality in patients with cerebral artery stenosis.