What is the purpose of the Dix-Hallpike (Dix-Hallpike test) and how is it used to diagnose and treat benign paroxysmal positional vertigo (BPPV)?

Dix-Hallpike Test: Diagnostic Gold Standard for Posterior Canal BPPV

Purpose and Clinical Application

The Dix-Hallpike maneuver is the gold standard diagnostic test for posterior canal benign paroxysmal positional vertigo (BPPV), designed to provoke characteristic vertigo and nystagmus by moving otoconia (calcium carbonate crystals) within the semicircular canals. 1, 2

The test serves two critical functions:

• Confirms the diagnosis of posterior canal BPPV through observation of specific nystagmus patterns 1, 3
• Identifies which ear is affected, guiding subsequent treatment with repositioning maneuvers 2, 4

How to Perform the Dix-Hallpike Maneuver

Pre-Test Preparation

• Warn the patient that the maneuver will likely provoke sudden intense vertigo and possibly nausea, but symptoms will typically resolve within 60 seconds 2
• Position the patient so their head can extend approximately 20 degrees below horizontal when supine, hanging off the edge of the examination table 2, 3

Execution Steps

1. Start with the patient sitting upright on the examination table 2
2. Turn the patient's head 45 degrees to one side (testing that ear) 4
3. Rapidly move the patient to supine position with the head extended 20 degrees below horizontal, maintaining the 45-degree head turn 2, 4
4. Hold this position for at least 60 seconds while observing for nystagmus and asking about vertigo 3
5. Return patient to sitting and observe for reversal nystagmus 3
6. Repeat the entire sequence for the opposite side 1, 2

Diagnostic Criteria for a Positive Test

A positive Dix-Hallpike test requires all four of the following characteristics 2, 3:

• Latency period: 5-20 seconds (rarely up to 60 seconds) between completing the positioning and onset of symptoms 3
• Characteristic nystagmus: Torsional (rotatory) and upbeating (toward the forehead) with a crescendo-decrescendo pattern 3
• Time-limited duration: Both vertigo and nystagmus resolve within 60 seconds from onset 2, 3
• Subjective vertigo: Patient reports spinning sensation, not just nystagmus alone 3

Identifying the Affected Ear

• The affected ear is the one positioned downward when the positive response occurs 4
• The nystagmus beats toward the affected ear (geotropic torsional component) 4
• Bilateral involvement can occur, particularly after head trauma, requiring testing of both sides 1, 3

Diagnostic Accuracy

The test has moderate diagnostic accuracy 2, 3:

• Sensitivity: 82% among specialty clinicians 1, 2
• Specificity: 71% 1, 2
• Positive predictive value: 83% 1, 3
• Negative predictive value: only 52% in primary care settings 1, 3

Critical Pitfall

A single negative test does NOT rule out BPPV due to the low negative predictive value 3. If clinical suspicion remains high:

• Repeat the Dix-Hallpike test at the same visit after holding the patient in various positions, as this allows canaliths to collect and may convert a false-negative to positive 5
• Perform a supine roll test to evaluate for lateral canal BPPV (10-15% of cases) 1, 2
• Consider repeating at a separate visit 1

Safety Considerations and Contraindications

Exercise extreme caution or avoid the Dix-Hallpike test in patients with 1, 2, 3:

• Significant vascular disease (theoretical stroke risk, though no documented cases) 1, 3
• Cervical stenosis or severe limitation of cervical range of motion 1, 2
• Severe kyphoscoliosis 1, 2
• Down syndrome 1
• Severe rheumatoid arthritis or ankylosing spondylitis 1, 3
• Cervical radiculopathies 1, 2
• Spinal cord injuries 1, 2
• Morbid obesity (may require additional assistance or specialized tilting tables) 1, 2

For high-risk patients, consider referral to specialists with tilting examination tables that allow safer performance 1, 3

When to Perform Alternative Testing

If the Dix-Hallpike test is negative but symptoms suggest BPPV 1, 2:

• Perform the supine roll test to assess for lateral semicircular canal BPPV 1, 2
• Lateral canal BPPV accounts for approximately 10-15% of BPPV cases and presents with similar symptoms 1, 2

If nystagmus is horizontal or atypical rather than the characteristic torsional upbeating pattern 3:

• Consider MRI of the brain, as acute brain lesions were detected in 11% of patients with episodic vertigo and atypical Dix-Hallpike findings 3

Transition to Treatment

Once a positive test confirms posterior canal BPPV, the same positioning can transition directly into treatment with the Epley maneuver (canalith repositioning procedure) 1, 6. This repositioning maneuver has approximately 80% success rate with 1-3 treatments 1.

The test may need to be repeated after treatment to confirm resolution, as nystagmus typically fatigues (reduced response) with repeated maneuvers, which is a normal finding 3, 6.