How do you differentiate and manage dizziness caused by stroke versus vertigo?

Differentiating and Managing Dizziness Caused by Stroke versus Vertigo

Distinguishing between stroke and peripheral vertigo is critical for patient outcomes, with the HINTS examination (Head-Impulse, Nystagmus, Test of Skew) being the most valuable tool for differentiation when performed properly. 1

Clinical Features to Differentiate Stroke from Peripheral Vertigo

Stroke-Related Dizziness

• Nystagmus patterns suggestive of central causes:
  • Downbeating nystagmus without torsional component
  • Direction-changing nystagmus without head position changes
  • Direction-switching nystagmus with gaze
  • Baseline nystagmus without provocative maneuvers 2
• Associated neurological symptoms:
  • Dysarthria, dysmetria, dysphagia
  • Sensory or motor deficits
  • Horner's syndrome 2
  • Gait abnormalities/cerebellar ataxia
  • Pronounced autonomic dysfunction 1
• Risk factors:
  • Sudden onset of symptoms
  • Vascular risk factors (hypertension, diabetes, hyperlipidemia)
  • Recent TIA in the preceding 90 days 2

Peripheral Vertigo (e.g., BPPV)

• Characteristic features:
  • Positional triggering with specific head movements
  • Brief duration (seconds to minutes)
  • Torsional nystagmus with Dix-Hallpike maneuver
  • Fatigability of symptoms with repeated positioning
  • No associated neurological symptoms 2
  • Responds to repositioning maneuvers 1

Diagnostic Approach

Initial Assessment

1. HINTS examination - superior to MRI in the first 48 hours:

   • Head-Impulse test (normal in stroke, abnormal in peripheral vertigo)
   • Nystagmus evaluation (direction-changing in stroke)
   • Test of Skew (vertical misalignment in stroke) 1

2. Additional clinical tests:

   • Dix-Hallpike maneuver for posterior canal BPPV
   • Romberg's test for balance assessment
   • Evaluation for other neurological deficits 1

When to Suspect Stroke

• Abnormal HINTS examination
• Neurological deficits beyond vertigo
• High vascular risk profile
• No response to appropriate BPPV treatment after 2-3 attempts
• Persistent symptoms despite appropriate management 1

Imaging Recommendations

• MRI brain (without contrast) is indicated for:
  • Acute vestibular syndrome with abnormal HINTS
  • Presence of neurological deficits
  • High vascular risk patients even with normal examination
  • Chronic undiagnosed dizziness not responding to treatment 1
• Note: Routine brain imaging is not recommended for typical BPPV with positive Dix-Hallpike test and no atypical features 1

Management Approach

For Stroke-Related Dizziness

1. Acute management:

   • Immediate neurological consultation
   • Aggressive medical management with antiplatelet therapy
   • Statin therapy and risk factor modification 3
   • Supportive care and monitoring

2. Secondary prevention:

   • Antiplatelet or anticoagulation therapy as appropriate
   • Vascular risk factor management
   • Regular follow-up 1

For Peripheral Vertigo (BPPV)

1. First-line treatment:

   • Canalith repositioning procedures (CRPs) specific to the canal involved:
     • Epley maneuver for posterior canal BPPV
     • Semont maneuver as an alternative 1

2. Symptomatic management:

   • Meclizine for short-term symptom relief 4
   • Vestibular rehabilitation for persistent symptoms 1

Important Caveats and Pitfalls

1. Don't miss stroke:

   • Up to 11% of patients with isolated vertigo/dizziness have stroke, most commonly in the cerebellum 5
   • Posterior circulation strokes can present with isolated vertigo without other neurological symptoms 6

2. Be cautious with imaging interpretation:

   • MRI can miss small strokes in the acute setting (false-negative rate up to 50%) 7
   • Clinical assessment may be more sensitive than early imaging 1

3. Consider risk stratification:

   • The TriAGe+ score can help identify stroke risk in patients with vertigo/dizziness (sensitivity 96.6% at cutoff of 5 points) 8

4. Recognize transient ischemic attacks:

   • Vertebrobasilar TIAs can present with isolated episodes of vertigo lasting less than 30 minutes
   • These may precede a stroke by weeks or months 1

5. Special considerations for elderly patients:

   • Assess fall risk and home safety
   • Consider multifactorial causes including medication side effects and orthostatic hypotension
   • Measure orthostatic blood pressure 1

By systematically evaluating patients with dizziness using these clinical features and diagnostic tools, clinicians can effectively differentiate between stroke and peripheral causes of vertigo, ensuring appropriate and timely management.