Benign Paroxysmal Positional Vertigo
A clinical diagnosis with a specific positional test — VEMP has no role in classic BPPV, but oVEMP abnormalities are common and reveal the utricular origin of the displaced otoconia.
What is BPPV?
Benign paroxysmal positional vertigo is brief, position-triggered vertigo caused by otoconia (tiny calcium-carbonate crystals normally embedded in the utricular macula) becoming displaced into one of the semicircular canals — most commonly the posterior canal. Diagnosis is made by the Dix-Hallpike test; treatment is by canalith repositioning (the Epley manoeuvre).
VEMP findings in BPPV
- oVEMP abnormalities are more common than cVEMP — consistent with the utricular origin of the displaced otoconia.[15]
- Reduced amplitudes and prolonged latencies have both been reported.
- Abnormalities are more frequent in recurrent and bilateral BPPV than in isolated single episodes.
Why the utricle?
The otoconia of BPPV originate principally from the utricular macula — the saccular macula sits in a different plane and is less likely to shed otoconia into the canal system. Persistent or recurrent BPPV may reflect an underlying utriculopathy that continues to release crystals, even after each manoeuvre clears them.[11,15]
When to consider VEMP in BPPV
- Recurrent BPPV despite successful repositioning.
- Bilateral BPPV.
- Atypical positional nystagmus that does not fit a single canal.
- Suspicion of secondary BPPV (post-trauma, post-viral).