What are the symptoms of a basilar stroke beyond dizziness?

Symptoms of Basilar Stroke Beyond Dizziness

Basilar artery occlusion strokes present with a wide range of symptoms beyond dizziness, including loss of consciousness, headache, nausea, vomiting, double vision, hearing loss, slurred speech, vertigo, imbalance, unilateral extremity weakness, ataxia, nystagmus, and visual field defects. 1

Clinical Presentation by Location

The symptoms of basilar stroke vary based on the location of the occlusion:

Top of the Basilar Syndrome

• Somnolence
• Peduncular hallucinosis (vivid visual hallucinations)
• Convergence nystagmus
• Skew deviation
• Oscillatory eye movements
• Retraction and elevation of the eyelids
• Vertical gaze paralysis 1

Mid-Basilar Occlusions

• Various pontine syndromes
• Cranial nerve deficits
• Motor deficits 1

Proximal Basilar Occlusions

• "Locked-in" syndrome (quadriplegia with preserved consciousness and vertical eye movements)
• Bulbar symptoms (difficulty swallowing, speaking) 1

Common Neurological Findings

• Motor Deficits: Unilateral or bilateral weakness, often affecting one side of the body 1
• Sensory Disturbances: Paresthesia or sensory loss 1
• Visual Abnormalities: Visual field defects, diplopia (double vision) 1
• Coordination Problems: Ataxia, incoordination 1
• Cranial Nerve Dysfunction: Multiple cranial nerve deficits 1, 2
• Altered Consciousness: Ranging from confusion to coma 1
• Speech Disorders: Dysarthria (slurred speech) 1
• Severe Headache: Particularly sudden onset 1

Diagnostic Challenges

Basilar artery occlusions are often difficult to diagnose promptly because:

1. Symptoms can be non-specific and mimic other conditions 1
2. The National Institutes of Health Stroke Scale (NIHSS) has limitations in detecting posterior circulation strokes as it focuses more on limb and speech impairments rather than cranial nerve lesions 1
3. Patients may present with subtle symptoms - some patients with posterior circulation stroke can have an NIHSS score of 0, with truncal ataxia being the most common neurological sign 1

Warning Signs Requiring Immediate Attention

Patients and healthcare providers should be particularly alert to:

• Any combination of dizziness with other neurological symptoms 1
• Sudden severe headache 1
• Any acute neurological deficit, even if mild or transient 1
• Symptoms that fluctuate or progress rapidly 1

Clinical Pitfalls to Avoid

1. Misdiagnosis: Basilar strokes are often misdiagnosed as inner ear disorders, migraine, or intoxication due to the prominence of dizziness and imbalance 1, 3
2. Delayed Recognition: Unlike hemispheric ischemia, basilar artery occlusion can mimic other clinical conditions, resulting in delays to clinical neurological evaluation 1
3. Underestimating Subtle Symptoms: Patients with posterior circulation strokes can present with subtle symptoms that may be dismissed 1
4. Failing to Recognize the Prodrome: There may be an extended prodrome that can potentially last days to months before a catastrophic basilar occlusion 1

Mortality and Outcomes

Basilar artery occlusions have high mortality rates (45-86%) and poor outcomes without prompt treatment 1. Even with advanced care, good clinical outcomes occur in only approximately 20% of cases 1. This emphasizes the critical importance of early recognition and intervention.

Remember that basilar artery occlusion is a medical emergency requiring immediate neuroimaging and consideration for thrombolytic or endovascular therapy, as time-sensitive interventions can significantly improve outcomes 2, 4.