What is the procedure for performing the Dix-Hallpike test for Benign Paroxysmal Positional Vertigo (BPPV)?

How to Perform the Dix-Hallpike Test

The Dix-Hallpike maneuver involves rapidly moving the patient from sitting upright with the head turned 45 degrees to one side, to lying supine with the head extended 20 degrees below horizontal, while observing for characteristic torsional upbeating nystagmus and vertigo after a 5-20 second latency period. 1, 2

Pre-Test Patient Preparation

• Warn the patient explicitly that the maneuver will provoke sudden intense vertigo and possibly nausea, but these symptoms will resolve within 60 seconds 1, 3
• Position the patient seated on the examination table so that when supine, their head can hang off the posterior edge of the table by approximately 20 degrees 1, 3
• Ensure you can safely support the patient's head throughout the entire maneuver without losing your own balance or support 1

Step-by-Step Procedure

Testing the Right Ear (Posterior Canal):

1. Starting position: Patient sits upright on the examination table with you standing at their right side 1

2. Head rotation: Turn the patient's head 45 degrees to the right to align the right posterior semicircular canal with the sagittal plane of the body 1

3. Rapid repositioning: Quickly move the patient from sitting to supine with the head extended 20 degrees below horizontal (head hanging position), maintaining the 45-degree head rotation 1, 3

4. Observation period: Hold this position for at least 60 seconds while observing the patient's eyes for nystagmus and asking about vertigo 2, 4

Testing the Left Ear:

• Repeat the entire sequence (steps 1-4) for the left side, turning the head 45 degrees to the left 1

Interpreting a Positive Test

A positive test requires all four of these characteristics 2, 3:

• Latency period: 5-20 seconds delay between completing head positioning and onset of symptoms (rarely up to 60 seconds) 2
• Characteristic nystagmus: Torsional (rotatory) and upbeating (toward the forehead) with a crescendo-decrescendo pattern 2
• Time-limited resolution: Both vertigo and nystagmus resolve within 60 seconds from onset 2, 3
• Subjective vertigo: Patient reports rotational spinning sensation 2

Critical Testing Considerations

Bilateral Testing is Mandatory:

• Always test both sides to determine which ear is affected or if bilateral involvement exists 1, 2
• Bilateral posterior canal BPPV occurs more commonly after head trauma 1, 3

Repeat Testing if Initially Negative:

• If the initial Dix-Hallpike is negative but clinical suspicion remains high, repeat the test after holding the patient in various positions 5
• Holding the patient in head-hanging and lateral positions allows canaliths to collect, potentially converting a false-negative test to positive 5
• The negative predictive value is only 52% in primary care settings, so a single negative test does not rule out BPPV 2, 3

Fatigue Phenomenon:

• When repeated immediately, the nystagmus and vertigo typically weaken (BPPV fatigue) 4
• This fatigue effect disappears within 30 minutes, after which the test will again elicit clear nystagmus 4
• Upon returning the patient to upright after a positive test, reversal of nystagmus direction may occur 2

Safety Contraindications and Precautions

Exercise extreme caution or avoid the test entirely in patients with 1, 2, 3:

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

For high-risk patients, consider referral to specialists with tilting examination tables that allow safer performance 2, 3

When the Dix-Hallpike is Negative or Atypical

• If symptoms suggest BPPV but Dix-Hallpike is negative, perform a supine roll test to evaluate for lateral semicircular canal BPPV, which accounts for 10-15% of BPPV cases 2, 3
• If the test produces horizontal nystagmus or spontaneous nystagmus without the characteristic pattern, obtain MRI of the brain, as acute brain lesions were detected in 11% of such patients 2
• In up to one-third of cases with atypical histories, Dix-Hallpike testing will still reveal positional nystagmus, strongly suggesting posterior canal BPPV 1, 2

Factors Affecting Diagnostic Accuracy

The test's accuracy can be influenced by 1, 3:

• Speed of head movements during the maneuver 1, 3
• Time of day when testing is performed 1, 3
• Angle of the occipital plane during the maneuver 1, 3

The Dix-Hallpike has moderate sensitivity (82%) and specificity (71%) among specialists, with a positive predictive value of 83% 2, 3