BPPV — Diagnosis and the Epley Manoeuvre

Benign paroxysmal positional vertigo is the most common cause of vertigo presenting to any clinician — general practitioners, emergency physicians, neurologists, and ENT surgeons all see it regularly. It is also one of the most satisfying conditions in medicine to treat: a specific physical manoeuvre, performed correctly at the bedside, resolves most cases in a single session. Understanding why it works requires understanding the anatomy that produces it.

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The Mechanism — Canaliths and the Semicircular Canals

The inner ear contains three semicircular canals on each side — posterior, anterior (superior), and horizontal — each oriented in a different plane to detect angular acceleration of the head. Each canal is a fluid-filled arc that terminates at the ampulla, where hair cells embedded in a gelatinous mass (the cupula) are deflected by fluid movement.

The utricle and saccule, the otolith organs, contain calcium carbonate crystals called otoconia (or canaliths). These crystals are denser than the surrounding endolymph. When the head moves, the inertia of the crystals causes them to lag behind, bending the hair cells and generating a signal that contributes to the perception of linear acceleration and gravity.

In BPPV, otoconia become displaced from the utricle and migrate into one of the semicircular canals — most commonly the posterior canal (approximately 85–90% of cases). Once inside the canal, they behave as free-floating particles that move under gravity when the head is repositioned. This produces an abnormal cupula deflection, which generates an intense but brief sense of rotation — vertigo — that is perfectly explained by a spinning sensation from one canal responding to head movement when it should not be.

The two main subtypes of BPPV reflect where the displaced otoconia are:

Canalithiasis: free-floating particles in the long arm of the canal. This is the most common form. When the head moves, the particles take a few seconds to start moving (latency), produce brief vertigo as they move through the canal, and fatigue with repeated testing as they gradually disperse.

Cupulolithiasis: particles adherent to or immediately adjacent to the cupula. This produces persistent vertigo with head position changes (because the cupula is always deflected) and does not fatigue. It is less common and harder to treat.

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The Presentation

BPPV has a characteristic history that, once learned, is difficult to miss. The key features:

Brief episodes of vertigo triggered by specific head positions. Moving from lying to sitting, rolling over in bed, looking up to a high shelf, or tilting the head back. The vertigo is position-triggered, not movement-triggered in a sustained sense — it resolves quickly once the head is still.

Short duration. Each episode typically lasts less than one minute, usually 20–40 seconds. It then resolves — even if the provoking position is maintained — because the canaliths settle.

Latency. There is a characteristic 1–5 second delay between assuming the provoking position and the onset of vertigo. This latency is the time it takes for the displaced otoconia to begin moving in the canal.

Fatigability. With repeated testing in the same position, the response diminishes. This reflects progressive dispersal of the canalith mass.

No hearing loss, no tinnitus, no aural fullness. BPPV is a mechanical problem, not a cochlear one. The presence of auditory symptoms should prompt reconsideration of the diagnosis — Menière’s disease, labyrinthitis, or a retrocochlear lesion may be responsible.

Often nocturnal onset. Many patients report waking at night with a room-spinning sensation. The recumbent position and head rolling during sleep are classic triggers.

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The Dix-Hallpike Test — Technique

The Dix-Hallpike test is the diagnostic gold standard for posterior canal BPPV. It reproduces the symptoms by rapidly placing the affected posterior canal in a plane where gravity acts on the displaced canaliths.

Set-up: The patient sits upright on the examination couch with enough space behind them to lie flat. Explain what will happen — the speed of the movement is important, and a patient who stiffens anticipatorily will resist the test. Warn them they may briefly feel dizzy.

Step 1: Turn the patient’s head 45° toward the ear you are testing. This aligns the posterior canal of that ear with the sagittal plane.

Step 2: With the head maintained at 45° rotation, bring the patient rapidly to the supine position with the head hanging 20–30° below the level of the couch (the Hallpike position). The speed of this movement matters — a slow descent reduces the inertial force on the canaliths and may produce a false-negative result.

Step 3: Observe the eyes for nystagmus. Keep the patient in this position for at least 30 seconds, even if they report dizziness, because the latency to nystagmus onset can take several seconds.

Step 4: Return the patient to sitting and observe again — a reversal nystagmus is sometimes seen on returning to upright.

Test the suspected ear first. If negative, test the other side.

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Reading the Nystagmus

The direction and character of the nystagmus tells you which canal is involved and whether the diagnosis is BPPV.

Posterior canal BPPV (classic positive Dix-Hallpike):

• Nystagmus is torsional and upbeat — the upper pole of the eye beats toward the lowermost (tested) ear
• Latency of 1–5 seconds before onset
• Duration less than 60 seconds
• Fatigable with repeated testing
• Patient reports vertigo that matches the nystagmus in direction and timing

This pattern is pathognomonic. The latency and fatigability are the distinguishing features from central causes.

If the nystagmus is:

• Present immediately without latency
• Non-fatigable with repeated testing
• Pure vertical (downbeat or upbeat without torsional component)
• Associated with neurological signs

— stop and consider a central cause. Posterior fossa pathology (cerebellar infarct, demyelination, posterior fossa tumour) can mimic BPPV on history but rarely produces the typical latent, fatigable, torsional nystagmus of canalithiasis. The HINTS examination (see the Approach to Vertigo article) distinguishes acute vestibular syndrome from stroke, but the Dix-Hallpike features themselves are the clue in positional vertigo.

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The Epley Canalith Repositioning Manoeuvre

The Epley manoeuvre moves the displaced otoconia from the posterior canal back into the utricle by rotating the patient’s head through a sequence of positions that arc the canal through 270°. Each position is held for 30 seconds to allow the canaliths to settle before the next movement.

The manoeuvre is performed on the side that tested positive on Dix-Hallpike.

Starting position: Patient sitting upright, head turned 45° toward the affected ear (same starting position as the Dix-Hallpike test).

Position 1 — Dix-Hallpike position: Rapidly bring the patient to lying with the head hanging 20–30° below the couch level, head still turned 45° toward the affected ear. Hold for 30 seconds.

Position 2 — Head rotation to opposite side: With the patient still supine and the neck extended, rotate the head 90° to the opposite side (now 45° away from the affected ear). Do this without lifting the head from the hanging position. Hold for 30 seconds.

Position 3 — Body roll: Keeping the head at the same angle of rotation (45° toward the unaffected ear), roll the patient onto their side so that both the head and body face downward (approximately prone position). The head is now pointing nose-down toward the floor. Hold for 30 seconds.

Position 4 — Return to sitting: Bring the patient back up to sitting while the head rotation is maintained. The head ends in the position facing 45° toward the unaffected side.

Throughout the manoeuvre, the aim is to move the canaliths from the posterior canal ampulla, along the long arm of the posterior canal, through the common crus, and into the utricle — using gravity and canal geometry to guide them.

After the manoeuvre: the patient may feel briefly dizzy. This is expected and indicates the canaliths are moving. Warn them in advance.

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Success Rate and Recurrence

The Epley manoeuvre is highly effective. The 2017 American Academy of Otolaryngology–Head and Neck Surgery clinical practice guideline (Bhattacharyya et al.) reports resolution rates of approximately 80% after a single treatment and over 90% with repeated treatments in posterior canal BPPV. It is recommended as the primary treatment; vestibular suppressant medications (betahistine, prochlorperazine) are not effective for the underlying mechanical cause.

Recurrence is common. Studies report recurrence rates of 15–50% over 1–5 years. Patients can be taught a home version of the Epley (or the simpler Brandt-Daroff exercises as an alternative) for self-management of recurrences.

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Horizontal Canal BPPV

Approximately 10–15% of BPPV involves the horizontal (lateral) semicircular canal rather than the posterior canal. It is diagnosed with the roll test (supine head roll): the patient lies supine and the examiner rapidly rotates the head 90° to each side in turn. Horizontal canal BPPV produces horizontal geotropic nystagmus (beating toward the ground) that is more intense on the affected side — distinguishing it from the torsional upbeat nystagmus of posterior canal involvement.

Treatment is with the Barbecue rotation manoeuvre (Lempert manoeuvre): the patient is rolled 360° in sequential 90° steps starting toward the unaffected side, repositioning the canaliths from the horizontal canal back to the utricle. Cupulolithiasis of the horizontal canal produces apogeotropic nystagmus (beating away from the ground) and is generally more treatment-resistant.

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Key Numbers

Parameter	Value
Posterior canal BPPV frequency	~85–90% of all BPPV
Nystagmus latency (positive Dix-Hallpike)	1–5 seconds
Nystagmus duration (positive Dix-Hallpike)	<60 seconds (typically 20–40 seconds)
Resolution after single Epley	~80%
Resolution after repeated Epley	>90%
Recurrence rate (1–5 years)	15–50%
Hold time at each Epley position	30 seconds

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Red Flags — When BPPV is Not the Diagnosis

BPPV is a clinical diagnosis of characteristic features. When those features are absent or additional features are present, look further:

• No latency on Dix-Hallpike → consider central positional nystagmus
• Non-fatigable nystagmus → central cause until proven otherwise
• Pure vertical nystagmus (downbeat especially) → cerebellar pathology, Arnold-Chiari malformation
• Associated neurological symptoms (diplopia, dysarthria, dysphagia, limb ataxia, Horner syndrome) → posterior fossa lesion
• Hearing loss or tinnitus with vertigo → Menière’s disease, labyrinthitis, acoustic neuroma
• Failure of multiple correctly performed repositioning manoeuvres → reconsider the diagnosis; canal variant, cupulolithiasis, or alternative pathology

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Frequently Asked Questions

Can BPPV resolve on its own? Yes. Spontaneous resolution occurs in a significant proportion of cases — approximately 25–50% of posterior canal BPPV resolves within a few weeks without treatment. However, the Epley manoeuvre resolves it in minutes rather than weeks, with no risk, and patients who are not treated often modify their activity significantly to avoid triggering positions, reducing quality of life. Treatment is preferred.

Should I restrict head position after the Epley? Early guidance recommended post-Epley activity restrictions (sleeping semi-upright, avoiding the affected side). The evidence for this does not support significant benefit, and most current guidelines do not mandate restriction. Patients should be reassured that normal head movement is acceptable.

Can I perform the Epley on a patient who becomes very distressed during Dix-Hallpike? Yes. Significant distress during the Dix-Hallpike — intense vertigo, nausea, even vomiting — indicates the test is positive and the canaliths are moving, which means the same movement sequence used in the Epley will move them further in the right direction. Warn the patient before proceeding, work quickly through the positions, and reassure them that the severity of symptoms during the manoeuvre predicts nothing about the final outcome.

Does BPPV cause falls? Yes, and this is clinically important in elderly patients. A brief but intense episode of vertigo when turning in bed or looking upward can cause significant loss of balance. BPPV is underdiagnosed in elderly patients who present after a fall — always consider it in any patient over 60 presenting with falls, particularly with a history of positional dizziness.

What if the Dix-Hallpike is negative on both sides but the history is typical of BPPV? BPPV can be intermittent — the canaliths may have temporarily dispersed or the patient may have spontaneously repositioned between onset and assessment. A classic history with negative Dix-Hallpike on the day of assessment does not exclude BPPV. Repeat the test on a different day, or perform it earlier in the morning (when the recumbent position during sleep tends to maximally concentrate canaliths in a provoking position).