What is the initial workup for a patient presenting with dizziness?

Initial Workup for Patients Presenting with Dizziness

The initial workup for a patient presenting with dizziness should focus on timing and triggers rather than subjective symptom descriptions, with targeted physical examination including the HINTS test to differentiate between peripheral and central causes.

Categorizing Dizziness by Timing and Triggers

The traditional approach of classifying dizziness into vertigo, presyncope, disequilibrium, and lightheadedness has limited clinical utility. Instead, focus on these key patterns:

1. Acute Vestibular Syndrome (AVS): Rapid onset of persistent vertigo (hours to days)

   • Evaluate with HINTS exam (Head Impulse, Nystagmus, Test of Skew)
   • Normal neurological exam with HINTS consistent with peripheral cause suggests vestibular neuritis 1
   • Abnormal neurological exam or HINTS suggesting central cause requires urgent imaging for stroke 1

2. Episodic Vestibular Syndrome:

   • Triggered: Brief episodes provoked by specific head movements
     • Perform Dix-Hallpike maneuver to diagnose BPPV 1
   • Spontaneous: Recurrent unprovoked episodes
     • With hearing loss/tinnitus: Consider Menière's disease 1
     • With headache/photophobia: Consider vestibular migraine 1

3. Chronic Vestibular Syndrome: Persistent dizziness/imbalance (weeks to months)

   • Evaluate for neurological, metabolic, or psychiatric causes

Essential Physical Examination Components

• Vital signs: Including orthostatic blood pressure measurements
• HINTS examination: For acute vestibular syndrome
  • Head Impulse test: Abnormal in peripheral causes, normal in central causes
  • Nystagmus: Direction-fixed horizontal in peripheral causes; direction-changing or vertical in central causes
  • Test of Skew: Vertical misalignment suggests central pathology 1
• Dix-Hallpike maneuver: To diagnose BPPV 1
• Neurological examination: To identify focal deficits suggesting central pathology
• Otologic examination: To identify ear pathology

Laboratory and Imaging Studies

• Initial imaging is NOT routinely indicated for patients with:

  • Typical BPPV with positive Dix-Hallpike test 1
  • Acute vestibular syndrome with normal neurological exam and HINTS test consistent with peripheral cause 1

• MRI head without IV contrast is recommended for:

  • Acute vestibular syndrome with abnormal neurological exam or HINTS test suggesting central cause
  • Persistent symptoms despite appropriate treatment
  • Atypical features or risk factors for cerebrovascular disease 1

• CT temporal bone or MRI with IAC protocol may be indicated for:

  • Vertigo with associated hearing loss or tinnitus to rule out vestibular schwannoma 1

Common Pitfalls to Avoid

1. Over-reliance on symptom quality: Patients struggle to describe dizziness quality but can reliably report timing and triggers 2

2. Missing posterior circulation strokes: Up to 25% of patients with AVS may have stroke, and many lack focal neurological deficits. The HINTS exam is more sensitive than early MRI for stroke detection when performed by trained practitioners 1

3. Unnecessary imaging: The diagnostic yield of head CT in patients with isolated dizziness is very low (~2%) 1

4. Failure to perform provocative testing: Dix-Hallpike and supine roll tests are essential for diagnosing BPPV 1

5. Overlooking medication effects: Many medications can cause dizziness; always review the patient's medication list 3

By following this approach focused on timing, triggers, and targeted examination, clinicians can efficiently differentiate between benign peripheral causes and potentially serious central causes of dizziness, leading to appropriate management and improved outcomes.