What is the appropriate approach to diagnose vertigo?

Diagnosing Vertigo: A Structured Clinical Approach

The diagnosis of vertigo begins with classifying the presentation into one of three temporal patterns—acute vestibular syndrome (AVS), episodic vestibular syndrome (EVS), or chronic vestibular syndrome (CVS)—followed by targeted physical examination maneuvers rather than routine imaging. 1, 2

Initial Classification by Temporal Pattern

The most critical first step is determining the timing and triggers of vertigo symptoms, which narrows the differential diagnosis more effectively than asking patients to describe the sensation itself 3:

• Acute Vestibular Syndrome (AVS): Continuous vertigo lasting days, with nystagmus present (e.g., stroke, vestibular neuritis) 1, 2
• Episodic Vestibular Syndrome (EVS): Recurrent vertigo episodes lasting seconds to hours
  • Triggered EVS: Provoked by head position changes (e.g., BPPV) 4
  • Spontaneous EVS: Occurs without positional triggers (e.g., vestibular migraine, Menière's disease) 1, 2
• Chronic Vestibular Syndrome (CVS): Persistent dizziness lasting months (e.g., PPPD, bilateral vestibulopathy) 1

Diagnosing Benign Paroxysmal Positional Vertigo (BPPV)

Posterior Canal BPPV

For patients with triggered episodic vertigo, perform the Dix-Hallpike maneuver as the gold standard diagnostic test. 4

The diagnostic criteria require all of the following 4:

• History: Repeated vertigo episodes with head position changes relative to gravity 4
• Dix-Hallpike maneuver positive when it provokes:
  • Torsional (rotatory) and upbeating nystagmus toward the forehead 4
  • Latency period of 5-20 seconds (rarely up to 60 seconds) between maneuver completion and symptom onset 4
  • Crescendo-decrescendo pattern with resolution within 60 seconds from nystagmus onset 4
• Repeat with opposite ear down if initial maneuver is negative 4

Critical caveat: The Dix-Hallpike has 82% sensitivity and 71% specificity among specialists, but lower accuracy in primary care (positive predictive value 83%, negative predictive value only 52%) 4. A negative test does not rule out BPPV and may require repeat testing at a separate visit 4.

Lateral Canal BPPV

If the patient has a history compatible with BPPV but the Dix-Hallpike test shows horizontal or no nystagmus, perform a supine roll test to assess for lateral semicircular canal BPPV. 4

Differentiating Central from Peripheral Causes

Red Flags Requiring Immediate Evaluation

Do not rely solely on symptom description—instead, look for these high-risk features 1, 2:

• Nystagmus patterns suggesting central pathology:
  • Downbeating nystagmus on Dix-Hallpike (especially without torsional component) 4
  • Direction-changing nystagmus without head position changes 4
  • Gaze-evoked nystagmus (beats right with right gaze, left with left gaze) 4
  • Baseline nystagmus without provocative maneuvers 4
• Associated neurologic signs: Dysarthria, dysmetria, dysphagia, sensory/motor deficits, Horner's syndrome 4
• Severe gait unsteadiness in patients without nystagmus 2
• Failure to respond to canalith repositioning or vestibular rehabilitation 4

HINTS Examination for AVS

For clinicians trained in its use, apply HINTS (Head Impulse, Nystagmus, Test of Skew) in patients with AVS who have nystagmus present. 2

Important limitation: As of 2023, HINTS testing is inaccurate when applied by emergency clinicians without specialized training, and most emergency physicians have not received this training 2. It is not standard of care in routine practice 2.

Add the finger rub test to further exclude stroke in patients with nystagmus 2.

Imaging Recommendations

When NOT to Image

Do not obtain radiographic imaging in patients who meet diagnostic criteria for BPPV in the absence of additional signs or symptoms inconsistent with BPPV. 4

Specifically avoid 2:

• CT head in triggered episodic vestibular syndrome (BPPV) 2
• Routine MRI in typical BPPV presentations 2
• CT head in spontaneous episodic vestibular syndrome unless concern for TIA 2
• CT head in AVS (insensitive for early stroke) 2

When to Consider Imaging

Obtain MRI as a confirmatory test in patients with central or equivocal HINTS examinations 2. The 2024 ACR guidelines note that imaging is unnecessary in typical BPPV but should be considered for atypical presentations including 4:

• Negative or atypical Dix-Hallpike testing with clinical suspicion (central positional vertigo) 4
• Younger patients with post-traumatic onset 4
• Elderly patients 4
• Unresponsive to repositioning maneuvers 4
• Short-term symptom recurrence 4

Use CT angiography or MRI angiography if there is concern for transient ischemic attack in spontaneous episodic presentations 2.

Vestibular Testing

Do not order vestibular testing in patients who meet diagnostic criteria for BPPV in the absence of additional vestibular signs or symptoms inconsistent with BPPV. 4

Transcranial Doppler ultrasound may help differentiate vertebrobasilar insufficiency-related vertigo from other causes in select cases 4.

Distinguishing Other Common Causes

Vestibular Migraine

Diagnostic criteria include 4:

• ≥5 episodes of vestibular symptoms lasting 5 minutes to 72 hours 4
• Current or history of migraine per International Headache Society criteria 4
• ≥1 migraine symptom during ≥50% of dizzy episodes (migrainous headache, photophobia, phonophobia, visual aura) 4
• Distinguishable from BPPV by spontaneous (not positional) triggers 4

Vestibular Neuritis

Presents as AVS with continuous vertigo, nystagmus, and no hearing loss 1. Consider short-term steroids as treatment 2.

Menière's Disease

Characterized by episodic vertigo with fluctuating hearing loss and tinnitus 1, 5.

Essential Training Recommendation

Emergency clinicians should receive training in bedside physical examination techniques for AVS (HINTS) and the diagnostic and therapeutic maneuvers for BPPV (Dix-Hallpike test and Epley maneuver). 2