Benign Paroxysmal Positional Vertigo (BPPV)

BPPV is the single most common cause of peripheral vertigo, characterised by brief episodes of spinning triggered by changes in head position. It is a mechanical disorder of the inner ear — free-floating otoconia in a semicircular canal — and is one of the few causes of vertigo that is both fully explained by simple physics and cured at the bedside without drugs. For NEET PG, the high-yield trio is: posterior canal involvement, the Dix-Hallpike test, and the Epley manoeuvre.

Definition & basic concept

BPPV is a peripheral vestibular disorder producing recurrent, brief (seconds, typically <1 minute) episodes of rotatory vertigo provoked by specific changes in head position relative to gravity — lying down, sitting up, rolling over in bed, looking up ("top-shelf vertigo"), or bending forward.

Key descriptors hidden in the name:

• Benign → self-limiting, non-life-threatening, no underlying CNS lesion.
• Paroxysmal → sudden, short-lived bursts.
• Positional → triggered by head position change, NOT by position maintenance.
• Vertigo → true illusion of movement (spinning), not light-headedness.

High-yield: BPPV vertigo is positional and momentary (lasts seconds). If the patient reports continuous vertigo lasting hours to days, think vestibular neuritis or Ménière's, NOT BPPV.

Relevant anatomy & pathophysiology

The vestibular labyrinth has two functional parts:

• Otolith organs (utricle & saccule): contain the macula with otoconia (calcium carbonate "ear rocks" / statoconia) embedded in the otolithic membrane; sense linear acceleration & gravity.
• Three semicircular canals (posterior, superior/anterior, lateral/horizontal): sense angular acceleration via the cupula in the ampulla.

In BPPV, otoconia detach from the utricular macula (degeneration, head trauma, ageing) and drift into a semicircular canal — most often the posterior canal, because it is the most gravity-dependent in the upright and supine positions.

Two mechanistic theories explain the symptoms:

Theory	Location of otoconia	Mechanism	Clinical correlate
Canalithiasis (Hall, Epley, Schuknecht)	Free-floating within the canal lumen (endolymph)	Particles move under gravity → drag endolymph → deflect cupula	Latency present, transient nystagmus (fatigues); explains classic posterior canal BPPV
Cupulolithiasis (Schuknecht's original)	Adherent to the cupula	Cupula becomes gravity-sensitive (heavy)	No/short latency, more persistent nystagmus; explains some horizontal-canal variants

High-yield: Canalithiasis is the accepted mechanism for the common posterior canal BPPV and is the basis for repositioning (Epley) manoeuvres. Cupulolithiasis classically explains the apogeotropic horizontal canal variant.

Canalith repositioning theory — the cornerstone of treatment — states that if the free particles are guided sequentially through the canal back into the utricle (where they cause no symptoms), the disease is cured. This is precisely what the Epley manoeuvre achieves.

Etiology

• Idiopathic / primary (~50–70%) — most common; degenerative loosening of otoconia with age. Peak incidence 5th–7th decades, female predominance.
• Secondary causes:
  • Head trauma — commonest identifiable cause in younger patients; often bilateral.
  • Vestibular neuritis preceding ("post-neuritic BPPV").
  • Ménière's disease.
  • Prolonged bed rest / supine positioning (post-surgery, dental procedures).
  • Migraine (vestibular migraine association).
  • Inner ear ischaemia, osteoporosis / low vitamin D (recurrent BPPV).

High-yield: In a young patient with post-traumatic bilateral BPPV, suspect mechanical dislodgement of otoconia. In recurrent BPPV, screen for vitamin D deficiency and osteoporosis.

Which canal? (frequency)

Canal	Frequency	Provoking test	Notes
Posterior (PSC)	~85–90% (most common)	Dix-Hallpike	Classic upbeating-torsional nystagmus
Lateral / Horizontal (HSC)	~5–15%	Supine roll (Pagnini–McClure) test	Geotropic (canalithiasis) or apogeotropic (cupulolithiasis) nystagmus
Superior / Anterior (SSC)	<1–2% (rarest)	Dix-Hallpike / straight head-hang	Downbeating nystagmus; consider central mimic

High-yield: Posterior semicircular canal is by far the most commonly affected — the default answer in any "most common type of BPPV" question.

Clinical features

• Recurrent brief vertigo triggered by positional change; each spell lasts seconds (<1 min), settling if the position is held.
• Common triggers: turning over in bed, getting in/out of bed, looking up, bending down.
• Often worst in the morning and on first lying down.
• Associated nausea; vomiting if severe.
• Sense of imbalance / unsteadiness may persist between attacks.

What is ABSENT (important negatives that separate it from other causes):

• No hearing loss
• No tinnitus
• No aural fullness
• No neurological deficits, no headache, no continuous vertigo

High-yield: BPPV has no cochlear symptoms (no deafness/tinnitus/fullness). Presence of fluctuating hearing loss + tinnitus + aural fullness + vertigo points to Ménière's disease instead.

Diagnosis — investigation of choice

BPPV is a clinical / bedside diagnosis. No imaging or audiometry is required in classic cases.

Dix-Hallpike (Nylen-Bárány) manoeuvre — TEST OF CHOICE for posterior canal BPPV

Stepwise approach:

1. Patient sits upright on the couch; head turned 45° towards the test ear.
2. Examiner rapidly lays the patient supine with the head extended ~20–30° below the horizontal (head hanging over the edge), maintaining the 45° rotation.
3. Observe the eyes for nystagmus and ask about vertigo; hold for at least 30 seconds.
4. Return slowly to sitting; observe for reversal nystagmus.
5. Repeat on the opposite side.

Diagnosis flow: Sit-up + head rotate 45° → rapid lay back, head hanging → wait (latency) → rotatory geotropic nystagmus + vertigo appear → fatigues on holding / reverses on sitting up → posterior canal BPPV (affected side = down/dependent ear).

The classic positive findings (a favourite MCQ stem):

Feature	Posterior canal BPPV (peripheral)
Latency	Present (1–5 s, up to ~15 s) before nystagmus starts
Direction	Geotropic, rotatory (torsional) + upbeating — towards the dependent (lower) ear
Duration / fatigue	Transient (<1 min); fatigues on repetition
Vertigo	Accompanies the nystagmus, intense
Reversal	Nystagmus reverses on sitting up
Suppression by fixation	Reduced by visual fixation (peripheral feature)

High-yield: The classic Dix-Hallpike triad for posterior canal BPPV = latency + geotropic rotatory (torsional) nystagmus + fatiguability. Nystagmus fast phase beats towards the undermost (affected) ear and is upbeating-torsional.

Supine Roll (Pagnini–McClure) test

Used when Dix-Hallpike is negative but history suggests BPPV — diagnoses horizontal canal BPPV. Patient supine, head flexed 30°, rapidly turn head to each side:

• Geotropic horizontal nystagmus (beating to ground) → canalithiasis; affected ear = side with stronger response.
• Apogeotropic nystagmus (beating away from ground) → cupulolithiasis; affected ear = side with weaker response.

When to image

MRI brain is indicated only if there are red flags suggesting a central cause: atypical/direction-changing nystagmus, persistent nystagmus without latency or fatigue, nystagmus not suppressed by fixation, headache, focal neuro signs, or failure to respond to repositioning.

BPPV (peripheral) vs Central positional vertigo — the classic differentiator

Parameter	Peripheral (BPPV)	Central (brainstem/cerebellar)
Latency	Present (few seconds)	Absent (immediate)
Fatiguability	Fatigues on repetition	Does not fatigue (persistent)
Direction of nystagmus	Fixed, geotropic, rotatory/torsional	Direction-changing / pure vertical (downbeat)
Duration	Transient (<1 min)	Prolonged / persistent
Vertigo severity	Severe, matches nystagmus	Mild / dissociated from nystagmus
Suppression by fixation	Suppressed	Not suppressed
Associated features	None	Headache, diplopia, dysarthria, ataxia, focal signs

High-yield: Down-beating nystagmus, direction-changing nystagmus, absence of latency, non-fatiguability, and failure to suppress with fixation all flag a CENTRAL lesion (e.g., cerebellar/brainstem) and mandate neuroimaging.

Management — treatment of choice

Canalith repositioning manoeuvres (definitive, first-line)

Epley manoeuvre — treatment of choice for posterior canal BPPV. It repositions otoconia from the posterior canal back to the utricle.

Stepwise Epley (for left posterior canal; mirror for right) — 4 sequential head positions, each held ~30 s (or until nystagmus stops):

1. Sit upright, head turned 45° to the affected (left) side.
2. Lie back rapidly to Dix-Hallpike position (head hanging, still 45° left) — wait.
3. Rotate head 90° to the opposite (right) side — wait.
4. Roll body and head a further 90° (now facing the floor, head ~135° from start) — wait.
5. Return to sitting with chin tucked.

Epley flow: Affected-ear-down (Dix-Hallpike) → turn head 90° to good side → roll onto good side, nose toward floor → sit up → particles delivered back into utricle → cure.

• Semont (liberatory) manoeuvre — alternative for posterior canal; rapid side-to-side movement.
• Lempert / Barbecue (BBQ) roll — 360° rotation for horizontal canal canalithiasis.
• Brandt-Daroff exercises — home-based habituation exercises; useful as adjunct or when manoeuvres incompletely successful, or for residual symptoms.

High-yield: Epley manoeuvre is the definitive treatment for posterior canal BPPV with cure rates of ~80–90% after 1–2 sessions. The Barbecue/Lempert roll is for the horizontal canal.

Role of drugs

• Vestibular suppressants (prochlorperazine, betahistine, antihistamines like cinnarizine/meclizine) are NOT curative and are generally discouraged — they only blunt symptoms, hinder central compensation, and may mask nystagmus during diagnostic testing.
• Short-term antiemetics may be used for severe nausea before a repositioning manoeuvre.

High-yield: Drugs do not cure BPPV. The mechanical repositioning manoeuvre is both diagnostic-guided and curative. Avoid long-term vestibular sedatives.

Surgery (last resort, refractory cases)

• Posterior canal occlusion (plugging) — current surgical treatment of choice for intractable BPPV.
• Singular neurectomy (section of the posterior ampullary/singular nerve) — historical, technically difficult, risk of sensorineural hearing loss.

Complications & prognosis

• Falls and injury, especially in the elderly — a major practical concern.
• Canal switch / conversion during repositioning (otoconia enter another canal — e.g., posterior to horizontal).
• Residual dizziness / disequilibrium after successful repositioning (common, self-limiting).
• Recurrence — significant; up to ~30–50% over several years. Recurrent BPPV warrants checking vitamin D / bone density.
• Overall prognosis is excellent; many cases also remit spontaneously over weeks as particles dissolve.

Key differentials of vertigo

Condition	Duration	Hearing loss / tinnitus	Trigger	Distinguishing point
BPPV	Seconds (<1 min)	Absent	Positional	Dix-Hallpike +ve; fatiguable rotatory nystagmus
Ménière's disease	Minutes–hours (20 min–24 h)	Present (fluctuating SNHL) + tinnitus + aural fullness	Spontaneous	Endolymphatic hydrops; low-frequency SNHL
Vestibular neuritis	Days (continuous)	Absent	Spontaneous (often post-viral)	Unidirectional horizontal nystagmus; abnormal head impulse test
Labyrinthitis	Days (continuous)	Present (SNHL)	Spontaneous	Neuritis + cochlear involvement
Vestibular migraine	Minutes–hours	Usually absent	Variable	Headache/photophobia; migraine history
Central (cerebellar/brainstem)	Variable/persistent	Variable	Positional or spontaneous	Direction-changing/downbeat nystagmus, focal signs, +ve HINTS

High-yield (HINTS exam): In acute continuous vertigo, HINTS (Head Impulse, Nystagmus, Test of Skew) distinguishes peripheral from central. A normal (negative) head impulse test, direction-changing nystagmus, or skew deviation suggests a central (stroke) cause — "INFARCT" pattern.

Recently asked / exam angle

• "Most common cause of peripheral vertigo / most common type of BPPV" → BPPV / posterior semicircular canal.
• Diagnostic test for posterior canal BPPV → Dix-Hallpike (Nylen-Bárány) manoeuvre.
• Treatment of choice for posterior canal BPPV → Epley (canalith repositioning) manoeuvre.
• Underlying mechanism / theory → Canalithiasis (free otoconia) per the canalith repositioning theory; cupulolithiasis for horizontal apogeotropic variant.
• Characteristic nystagmus of BPPV → geotropic, rotatory (torsional) upbeating, with latency and fatiguability, suppressed by fixation.
• Differentiate from central vertigo → BPPV has latency + fatiguability + fixation suppression; central is non-fatiguable, direction-changing/downbeating, not suppressed by fixation. (A perennial NEET PG one-liner.)
• Test for horizontal canal BPPV → Supine roll (Pagnini–McClure); treatment = Lempert/Barbecue roll.
• BPPV vs Ménière's: BPPV has no auditory symptoms; Ménière's has the triad of vertigo + fluctuating SNHL + tinnitus ± aural fullness.
• Recurrent BPPV → check vitamin D / osteoporosis.
• Image-based: identifying the head positions of the Epley manoeuvre sequence.

Rapid revision

1. BPPV = commonest cause of peripheral vertigo; brief positional spinning lasting seconds.
2. Posterior semicircular canal is the most commonly involved (~85–90%).
3. Mechanism = canalithiasis (free-floating otoconia from the utricle); basis of canalith repositioning theory.
4. No hearing loss, tinnitus, or aural fullness — pure vestibular symptoms.
5. Diagnostic test = Dix-Hallpike (Nylen-Bárány) manoeuvre.
6. Positive Dix-Hallpike = latency + geotropic rotatory (torsional) upbeating nystagmus + fatiguability; beats toward the undermost (affected) ear.
7. Treatment of choice = Epley manoeuvre; cure ~80–90%; drugs are not curative.
8. Horizontal canal BPPV → Supine roll test to diagnose, Lempert/Barbecue roll to treat.
9. Brandt-Daroff exercises = home adjunct/habituation.
10. Central red flags = downbeat / direction-changing nystagmus, no latency, non-fatiguable, not suppressed by fixation → image the brain.
11. Refractory BPPV → posterior canal occlusion (plugging) is the surgical option of choice.
12. Recurrence is common (~30–50%); screen for vitamin D deficiency / osteoporosis.