What are the guidelines for diagnosing various types of vertigo using clinical tests and physical examination maneuvers?

Guideline-Based Approach to Diagnosing Vertigo Types Using Clinical Tests and Physical Examination

Initial Clinical Classification by Timing and Triggers

The first step in diagnosing vertigo is to classify the presentation by timing (acute vs. episodic vs. chronic) and triggers (positional vs. spontaneous), which narrows the differential diagnosis and directs specific physical examination maneuvers. 1

The four distinct vestibular syndromes are:

• Triggered Episodic Vestibular Syndrome: Episodes lasting seconds to <1 minute, provoked by head position changes (e.g., BPPV) 1
• Spontaneous Episodic Vestibular Syndrome: Episodes lasting minutes to hours without positional triggers (e.g., vestibular migraine, Ménière's disease) 1
• Acute Vestibular Syndrome: Continuous dizziness lasting days to weeks with nausea, vomiting, and intolerance to head motion (e.g., vestibular neuritis, stroke) 1
• Chronic Vestibular Syndrome: Persistent dizziness lasting weeks to months (e.g., anxiety disorders, medication effects) 1

Diagnosing Benign Paroxysmal Positional Vertigo (BPPV)

Posterior Canal BPPV (Most Common)

Perform the Dix-Hallpike maneuver as the gold-standard diagnostic test when a patient reports brief vertigo triggered by head position changes. 1, 2, 3

Dix-Hallpike Maneuver Technique:

• Bring the patient from upright to supine position with head turned 45° to one side and neck extended 20° with the affected ear down 1
• Observe for characteristic nystagmus with 5-20 seconds latency (occasionally up to 60 seconds) 2
• Positive test shows torsional, upbeating nystagmus directed toward the forehead 1, 2
• Nystagmus follows a crescendo-decrescendo pattern and resolves within 60 seconds of onset 2
• If initial maneuver is negative, repeat with the opposite ear down 1, 2

Performance characteristics: Sensitivity ≈82%, specificity ≈71% among specialists; positive predictive value ≈83% in primary care 2

Critical caveat: A negative Dix-Hallpike does not exclude BPPV; repeat testing on a separate visit may be required 2

Lateral (Horizontal) Canal BPPV

If the Dix-Hallpike test exhibits horizontal nystagmus or no nystagmus in a patient with a history compatible with BPPV, perform the supine roll test to assess for lateral semicircular canal BPPV. 1, 2

Supine Roll Test Technique:

• Position patient supine with head in neutral position
• Rapidly turn head 90° to one side, then to the other
• Observe for horizontal nystagmus that changes direction with head position 1

Differentiating Central from Peripheral Causes

Red-Flag Nystagmus Patterns Indicating Central Pathology

The following nystagmus findings strongly suggest a neurologic cause rather than peripheral vestibular disorder and require urgent neuroimaging:

• Downbeating nystagmus on Dix-Hallpike without torsional component 1, 2
• Direction-changing nystagmus occurring without head position changes (periodic alternating nystagmus) 1, 2
• Gaze-evoked nystagmus (beats in the direction of gaze) 1, 2
• Persistent baseline nystagmus without provocative maneuvers (though this can also indicate vestibular neuritis) 1, 2

Additional Neurologic Red Flags

Associated findings that mandate evaluation for central causes (particularly posterior circulation stroke):

• Dysarthria, dysmetria, or dysphagia 1
• Focal sensory or motor deficits 1
• Horner's syndrome 1
• Severe gait unsteadiness out of proportion to nystagmus 3
• Failure to improve after canalith repositioning procedures or vestibular rehabilitation 1, 2

HINTS Examination for Acute Vestibular Syndrome

For patients with continuous vertigo lasting >24 hours with nystagmus, clinicians trained in HINTS examination should use this three-component bedside test to distinguish stroke from vestibular neuritis. 3

HINTS Components:

• Head Impulse Test (HIT): Normal (corrective saccade absent) suggests central cause 3
• Nystagmus: Direction-changing or vertical nystagmus suggests central cause 3
• Test of Skew: Vertical ocular misalignment suggests central cause 3

Important limitation: HINTS testing is inaccurate when applied by emergency clinicians without specialized training and should not be considered standard of care in routine practice as of 2023 3

Diagnosing Vestibular Migraine

Vestibular migraine requires all of the following diagnostic criteria:

• ≥5 episodes of vestibular symptoms lasting 5 minutes to 72 hours 1, 2
• Current or history of migraine according to International Headache Society criteria 1, 2
• ≥1 migraine symptom (migrainous headache, photophobia, phonophobia, visual aura) during at least 50% of dizzy episodes 1, 2
• Other causes ruled out by appropriate investigations 1

Key distinguishing feature: Episodes are triggered spontaneously rather than by positional changes, categorizing this as spontaneous episodic vestibular syndrome 1, 2

Diagnosing Ménière's Disease

Ménière's disease is characterized by the following clinical constellation:

• Discrete episodic attacks of sustained vertigo (not brief positional vertigo) 1
• Fluctuating hearing loss in the affected ear 1
• Aural fullness 1
• Tinnitus in the affected ear 1
• Episodes typically last minutes to hours 1

Critical differentiating feature: The presence of fluctuating hearing loss distinguishes Ménière's disease from BPPV, which has no associated hearing loss 1

Important caveat: Elderly patients with long-standing Ménière's disease may not manifest frank vertigo but rather present with episodes of vague dizziness 1

Other Otologic Causes to Differentiate

Superior Canal Dehiscence (SCD)

SCD differs from BPPV in that vertigo is induced by pressure changes (Valsalva maneuver) rather than position changes. 1

• May present with conductive hearing loss on audiometry 1
• Diagnosed via CT of temporal bones or vestibular evoked myogenic potential testing 1

Perilymph Fistula

Similar to SCD, perilymph fistula produces episodes of vertigo and nystagmus triggered by pressure rather than position. 1

Vestibular Neuritis

Vestibular neuritis presents as acute vestibular syndrome with:

• Sudden severe vertigo lasting 12-36 hours with decreasing disequilibrium over 4-5 days 1
• Profound nausea and vomiting 1
• No hearing loss, tinnitus, or aural fullness (distinguishes from labyrinthitis) 1
• Persistent baseline nystagmus without provocation 1

Imaging and Testing Recommendations

When NOT to Order Imaging

Do not obtain radiographic imaging in patients who meet diagnostic criteria for BPPV in the absence of additional signs or symptoms inconsistent with BPPV. 1, 2, 3

Do not order vestibular testing in patients who meet diagnostic criteria for BPPV without additional vestibular signs or symptoms inconsistent with BPPV. 1, 2

CT of the head is unnecessary for triggered episodic vestibular syndrome (BPPV). 2, 3

When to Consider MRI

MRI should be considered for atypical presentations including:

• Negative or atypical Dix-Hallpike results raising suspicion for central positional vertigo 2
• Post-traumatic onset of vertigo 2
• Elderly patients with new-onset vertigo 2
• Lack of response to repositioning maneuvers 2
• Short-term recurrence of symptoms 2
• Central or equivocal HINTS examination findings 3

Assessment of Modifying Factors

Assess all BPPV patients for factors that modify management:

• Impaired mobility or balance 1
• Central nervous system disorders 1
• Lack of home support 1
• Increased risk for falling (particularly in elderly patients, who have 12-fold increased fall risk when symptomatic) 1