Benign Paroxysmal Positional Vertigo (BPPV)

Definition & Epidemiology

Pathophysiology

1. Canalithiasis (more common) - Otoconia (calcium carbonate crystals) detach from the otolith (utricle macula) and float freely as debris ("canaliths") in the endolymph of the semicircular canal. With head movement, these particles gravitate to the most dependent part of the canal and induce endolymph currents that deflect the cupula, triggering vertigo.
2. Cupulolithiasis - Debris becomes adherent to the cupula itself, making it inappropriately gravity-sensitive.

• Posterior semicircular canal - ~90% of cases
• Horizontal (lateral) canal - ~10% of cases
• Superior canal - rare

Precipitating Factors

• Post-traumatic (head injury) - ~17% of cases
• Viral neurolabyrinthitis - ~15% of cases
• Osteoporosis - associated with higher frequency
• Often idiopathic

Clinical Features

• Vertigo on lying down, rolling over in bed, bending over and straightening up, or tilting the head back
• Often begins in middle of the night or early morning while shifting during sleep
• Episodes < 1 minute, but may recur for months

• Triggered by head position change (not by a sustained position)
• Latency of onset (few seconds after positioning)
• Brief duration (< 30-40 s, usually < 15 s)
• Reversal of nystagmus direction on sitting up
• Fatigability - nystagmus diminishes and disappears with repetition of the maneuver, returns only after prolonged rest
• No associated hearing loss or other ear signs

Diagnosis

Dix-Hallpike Maneuver (for posterior canal BPPV)

1. Patient sits upright on examination table
2. Head turned 45 degrees toward the ear being tested (aligns posterior canal with the sagittal plane)
3. Patient is rapidly brought to recumbency with the head hanging 30-40 degrees over the table edge

• Latency of 2-10 seconds
• Vertical-torsional nystagmus: fast phase toward the forehead (upbeating), torsional component beats the top of the eye toward the ground (geotropic torsion)
• The affected ear is the one that is downward when vertigo is elicited
• Nystagmus lasts < 30-40 s and reverses direction on returning to sitting
• Fatigues with repeated testing

Treatment

1. Epley Canalith Repositioning Maneuver (CRM) - First Line for Posterior Canal Canalithiasis

• A. Dix-Hallpike position with head rotated 45° right, neck slightly extended - head hanging right
• B. Once nystagmus/vertigo ceases, head rotated 45-60° toward the opposite (left) ear
• C. Patient rolled onto side with head continuing to turn until nearly face-down; held 10-15 s
• D. Head kept turned left as patient is brought back to sitting

Note: The last face-down step is sometimes incorrectly omitted - it is necessary for complete repositioning. An incomplete maneuver risks converting posterior canal to the harder-to-treat lateral canal variant.

2. Semont (Liberatory) Maneuver - for Cupulolithiasis

3. Brandt-Daroff Exercises - Habituation

• Persistent BPPV unresolved with CRM or Semont
• Residual vertigo without nystagmus
• Patients who cannot tolerate CRM

4. Horizontal Canal BPPV

5. Surgical (rare)

Natural History & Prognosis

• Many attacks resolve spontaneously over weeks to months
• In the elderly, attacks may recur over years with no long-term consequences
• ~80% respond to a single Epley maneuver session
• Instruction to avoid head-down position for 24 hrs post-Epley was previously recommended but recent studies suggest it is not necessary

Recent Evidence (2024-2026)