What are the recommended tests for diagnosing vertigo?

Diagnostic Testing for Vertigo

The diagnosis of vertigo is primarily clinical, based on history, physical examination, and specific bedside maneuvers—particularly the Dix-Hallpike test for benign paroxysmal positional vertigo (BPPV)—with imaging and laboratory testing reserved only for atypical presentations, neurological red flags, or diagnostic uncertainty. 1, 2

Essential Bedside Tests

Dix-Hallpike Maneuver (Primary Diagnostic Test)

• This is the gold standard test for posterior canal BPPV, the most common cause of vertigo, accounting for 42% of cases in primary care. 1
• The test is positive when it provokes characteristic torsional upbeating nystagmus with a latency period of 5-20 seconds, increasing then resolving within 60 seconds. 1
• No additional testing (imaging, labs, or vestibular function tests) is needed when diagnostic criteria are met. 1, 2

Supine Roll Test

• Use this test when horizontal nystagmus is observed or when Dix-Hallpike is negative but history suggests BPPV. 1
• For geotropic nystagmus: the side with strongest nystagmus is the affected ear. 1
• For apogeotropic nystagmus: the side opposite the strongest nystagmus is the affected ear. 1

HINTS Examination (For Acute Vestibular Syndrome)

• This three-component bedside test (Head Impulse, Nystagmus, Test of Skew) distinguishes peripheral from central causes in patients with acute continuous vertigo. 1, 3
• Central causes require urgent neuroimaging and management. 1, 4

When Additional Testing IS Indicated

Neuroimaging (MRI Brain with DWI, NOT CT)

• Order MRI only when neurological red flags are present: diplopia, dysarthria, ataxia, focal weakness, severe headache, or abnormal cranial nerve examination. 1, 2, 5
• The positivity rate of head CT in emergency department vertigo patients is only 2%, making it inadequate for ruling out stroke. 1
• MRI with diffusion-weighted imaging has 12% diagnostic yield when neurological findings are present, versus only 4% with isolated dizziness. 1

Vestibular Function Testing (ENG/VNG)

Do NOT order these tests routinely. They are appropriate only when: 6, 2

• Diagnosis remains unclear after clinical assessment
• Clinical presentation is atypical for common vestibular disorders
• Positional testing elicits equivocal or unusual nystagmus patterns
• Patient fails to respond to appropriate treatment
• Multiple concurrent vestibular disorders are suspected
• Recurrent symptoms despite adequate treatment

Audiometry

• Only obtain audiometry when hearing loss or tinnitus is part of the presentation, suggesting Ménière disease. 1, 2
• Not indicated for typical BPPV or vestibular neuritis without auditory symptoms. 2

What NOT to Order

Laboratory Testing

• The American Academy of Otolaryngology-Head and Neck Surgery explicitly recommends against routine laboratory testing for vertigo. 2
• Blood work does not improve diagnostic accuracy for BPPV, vestibular neuritis, or Ménière disease. 2

Routine Imaging for Typical BPPV

• Do not order MRI for typical BPPV when diagnostic criteria are met—costs are not justified and imaging does not improve diagnostic accuracy. 2

Routine Vestibular Testing

• ENG/VNG testing should not be ordered when clear diagnostic criteria are met for BPPV or Ménière disease with typical history. 6, 2
• Unnecessary testing leads to delays in treatment, increased costs, and patient discomfort. 6

Critical Red Flags Requiring Urgent Evaluation

Central Pathology Indicators

• Downbeating nystagmus on Dix-Hallpike without torsional component indicates central pathology, not BPPV. 5
• Direction-changing nystagmus without head position changes (periodic alternating nystagmus) suggests central pathology. 5
• Gaze-evoked nystagmus indicates central pathology. 5
• Baseline nystagmus without provocative maneuvers suggests central pathology. 5

Vascular Risk Factors

• In patients with episodic vertigo and vascular risk factors, conventional diagnostic angiography may be needed to evaluate for vertebrobasilar insufficiency or vertebral artery dissection. 1
• CTA demonstrates nearly 100% sensitivity for vertebral artery dissection. 1

Common Pitfalls to Avoid

• Do not repeat the Dix-Hallpike maneuver multiple times to demonstrate fatigability—this unnecessarily subjects patients to repeated vertigo and may interfere with immediate treatment. 1
• Normal vestibular test results do not rule out vestibular disorders—results fluctuate throughout disease course and correlate poorly with patient-perceived disability. 6
• Do not miss central pathology by failing to assess brainstem/cerebellar signs—10% of cerebellar strokes present similarly to peripheral vestibular processes. 5
• Avoid ordering a "routine vertigo workup"—this leads to unnecessary costs, delays, and does not improve diagnostic accuracy when clinical diagnosis is clear. 2