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

Initial Workup for Dizziness

The initial workup for dizziness should focus on categorizing the presentation by timing and triggers rather than the patient's subjective description, followed by targeted bedside examination—most patients do not require imaging or laboratory testing. 1, 2

Step 1: Categorize by Timing and Triggers

The most critical first step is determining which of four vestibular syndromes the patient has, as this drives all subsequent evaluation 1, 2, 3:

• Brief episodic vertigo (seconds to minutes): Triggered by head position changes—suspect BPPV 1, 2
• Spontaneous episodic vertigo (minutes to hours): No positional trigger—suspect vestibular migraine or Ménière's disease 1, 2
• Acute vestibular syndrome (days to weeks): Constant persistent symptoms—suspect vestibular neuritis vs. posterior circulation stroke 1, 3
• Chronic vestibular syndrome (weeks to months): Persistent symptoms—suspect medication side effects, anxiety, or structural lesions 1, 2

Common pitfall: Do not rely on patients describing "spinning" versus "lightheadedness"—these descriptions are inconsistent and do not distinguish benign from dangerous causes 1, 3.

Step 2: Obtain Targeted History

Focus on these specific elements 1, 2, 3:

• Duration and onset: Seconds (BPPV), minutes to hours (migraine/Ménière's), days (neuritis/stroke) 1
• Triggers: Positional changes, standing, specific head movements 1, 2
• Associated symptoms:
  • Hearing loss, tinnitus, aural fullness → Ménière's disease 1, 2
  • Headache, photophobia, phonophobia → vestibular migraine 1
  • Neurologic symptoms (diplopia, dysarthria, numbness, weakness) → central cause 2, 3
• Vascular risk factors: Age >50, hypertension, diabetes, atrial fibrillation, prior stroke 1, 3
• Medication review: Antihypertensives, sedatives, anticonvulsants, psychotropic drugs are leading causes of chronic dizziness 1
• Fall history: Number of falls in past year, circumstances, injuries sustained 1

Step 3: Perform Targeted Physical Examination

For All Patients 2, 3:

• Observe for spontaneous nystagmus at rest 2
• Complete neurologic examination: Cranial nerves, cerebellar testing (finger-to-nose, heel-to-shin), gait assessment 2, 3
• Orthostatic vital signs: Check if presyncope suspected 4, 5

For Brief Episodic Vertigo (Suspected BPPV) 1, 2:

• Dix-Hallpike maneuver: Diagnostic criteria include 5-20 second latency, torsional upbeating nystagmus toward affected ear, symptoms resolving within 60 seconds 1, 2
• Supine roll test: For horizontal canal BPPV 2, 6

For Acute Vestibular Syndrome (Suspected Neuritis vs. Stroke) 1, 3:

• HINTS examination (only if trained): Head impulse, nystagmus pattern, test of skew 1, 3
• Critical point: HINTS has 100% sensitivity for stroke when performed by trained practitioners (vs. 46% for early MRI), but is unreliable when performed by non-experts 1, 3

Major pitfall: 75-80% of patients with posterior circulation stroke have NO focal neurologic deficits—a normal neurologic exam does NOT exclude stroke 1, 3.

Step 4: Determine Need for Imaging

NO Imaging Indicated 1, 2, 3:

• Brief episodic vertigo with positive Dix-Hallpike test and no red flags 1, 2
• Acute persistent vertigo with normal neurologic exam AND peripheral HINTS by trained examiner (if low vascular risk) 1, 3
• Nonspecific dizziness without vertigo, ataxia, or neurologic deficits 1

MRI Brain WITHOUT Contrast Indicated 1, 2, 3:

• Abnormal neurologic examination 1, 2, 3
• HINTS examination suggesting central cause 1, 3
• High vascular risk patients with acute vestibular syndrome (even with normal exam)—11-25% have posterior circulation stroke 1, 3
• Unilateral or pulsatile tinnitus 1, 3
• Asymmetric hearing loss 1, 3
• Progressive neurologic symptoms 1, 2

MRI Head and Internal Auditory Canal WITH and WITHOUT Contrast 7, 2:

• Chronic recurrent vertigo with unilateral hearing loss or tinnitus (to exclude vestibular schwannoma) 2
• Suspected Ménière's disease requiring definitive diagnosis 7

Critical imaging facts: CT head has <1% diagnostic yield for isolated dizziness and misses most posterior circulation infarcts—MRI with diffusion-weighted imaging is far superior (4% diagnostic yield) 1, 2. CT temporal bone is only useful for suspected structural ear abnormalities, not routine dizziness workup 7, 2.

Step 5: Laboratory Testing

Laboratory testing has very low yield and is not routinely indicated 1, 4:

• Check fingerstick glucose immediately—hypoglycemia is the most frequently identified unexpected abnormality 1
• Basic metabolic panel: Only if history/exam suggests specific abnormalities (dehydration, electrolyte disturbance) 1
• Avoid routine comprehensive laboratory panels—they rarely change management 1

Red Flags Requiring Urgent Evaluation 1, 3:

• Focal neurological deficits 1, 3
• Sudden hearing loss 1, 3
• Inability to stand or walk 1, 3
• Downbeating nystagmus or other central nystagmus patterns 1, 3
• New severe headache accompanying dizziness 1, 3
• Failure to respond to appropriate vestibular treatments 1

Common Pitfalls to Avoid

• Do not rely on symptom quality descriptions—focus on timing and triggers instead 1, 3
• Do not assume normal neurologic exam excludes stroke in acute vestibular syndrome 1, 3
• Do not order imaging for typical BPPV with positive Dix-Hallpike 1, 2
• Do not use CT instead of MRI when stroke is suspected 1, 2
• Do not fail to assess fall risk in elderly patients—dizziness increases fall risk 12-fold 1
• Do not overlook medication side effects as a reversible cause of chronic dizziness 1