What is the initial approach to evaluating a patient presenting with dizziness?

Initial Approach to Evaluating Dizziness

The initial approach to evaluating dizziness should focus on categorizing the symptom into one of four types: Acute Vestibular Syndrome (AVS), Triggered Episodic Vestibular Syndrome, Spontaneous Episodic Vestibular Syndrome, or Chronic Vestibular Syndrome, as this classification is more clinically useful than the traditional vertigo/presyncope/disequilibrium/lightheadedness categories. 1

Step 1: Characterize the Dizziness Pattern

Focus on timing and triggers rather than the quality of symptoms:

• Acute Vestibular Syndrome (AVS): Continuous dizziness lasting days to weeks

  • Associated with nausea, vomiting, head motion intolerance
  • Common causes: Vestibular neuritis, labyrinthitis, posterior circulation stroke

• Triggered Episodic Vestibular Syndrome: Brief episodes triggered by specific actions

  • Typically lasting <1 minute
  • Common causes: Benign Paroxysmal Positional Vertigo (BPPV), central paroxysmal positional vertigo

• Spontaneous Episodic Vestibular Syndrome: Episodes not triggered by specific actions

  • Lasting minutes to hours
  • Common causes: Vestibular migraine, Ménière's disease, TIA

• Chronic Vestibular Syndrome: Dizziness lasting weeks to months

  • Common causes: Anxiety, medication side effects, posterior fossa masses

Step 2: Perform Targeted Physical Examination

Based on the dizziness pattern, perform these key examinations:

For Triggered Episodic Vestibular Syndrome (suspected BPPV):

• Dix-Hallpike maneuver: Look for delayed onset of vertigo and nystagmus after position change, upbeat and torsional nystagmus lasting <60 seconds 1
• Supine Roll Test: If Dix-Hallpike is negative but BPPV is still suspected (evaluates lateral canal BPPV)

For Acute Vestibular Syndrome (suspected vestibular neuritis vs. stroke):

• HINTS examination:
  • Head-Impulse: Abnormal in peripheral causes, normal in central causes
  • Nystagmus: Direction-fixed in peripheral causes, direction-changing in central causes
  • Test of Skew: Normal in peripheral causes, abnormal in central causes
  • HINTS+ (adds hearing assessment): 99% sensitivity for central causes 1

For all patients:

• Orthostatic blood pressure measurement
• Neurological examination
• Assessment for baseline nystagmus

Step 3: Identify Red Flags for Central Causes

Watch for these concerning features:

• Direction-changing nystagmus without changes in head position
• Downbeating nystagmus on Dix-Hallpike
• Baseline nystagmus without provocative maneuvers
• Failure to respond to appropriate repositioning maneuvers
• Associated neurological symptoms or signs
• Posterior circulation stroke can present with isolated dizziness in up to 25% of cases 1

Step 4: Consider Modifying Factors

Assess for factors that may modify management:

• Impaired mobility or balance
• CNS disorders
• Lack of home support
• Increased risk for falling, particularly in elderly patients 2

Step 5: Determine Need for Imaging

• MRI head without IV contrast is recommended for:

  • AVS with abnormal HINTS exam
  • AVS with neurological deficits
  • High vascular risk patients with AVS even with normal exam 1

• CT head without IV contrast may be considered when MRI is not immediately available for high-risk patients, but has low yield (<1%) in isolated dizziness without neurological deficits 1

• No imaging is typically needed for typical BPPV with positive Dix-Hallpike test 1

Step 6: Treatment Based on Diagnosis

• BPPV: Perform appropriate Canalith Repositioning Procedure (e.g., Epley maneuver for posterior canal BPPV)
• Vestibular neuritis: Consider steroids
• Ménière's disease: Low-salt diet, diuretics, and vestibular suppressants during acute attacks
• Persistent symptoms: Reevaluate for correct diagnosis, consider CNS disorders that can masquerade as BPPV (3% of treatment failures) 2

Common Pitfalls to Avoid

1. Relying solely on symptom quality descriptions: Patients struggle to describe dizziness quality but can more consistently identify timing and triggers 3

2. Missing stroke in AVS: Up to 25% of posterior circulation strokes can present with isolated dizziness 1

3. Overuse of imaging: CT and MRI have low yield in typical BPPV and should be reserved for cases with red flags 1

4. Failure to reassess treatment failures: Patients with persistent symptoms after initial treatment should be reevaluated for persistent BPPV or underlying CNS disorders 2

5. Neglecting fall risk assessment: Particularly important in elderly patients with BPPV, as they have a 12-fold increase in fall risk 2