A 67-year-old woman has had three episodes of right posterior canal BPPV over 18 months, each successfully treated with the Epley manoeuvre. She now returns with a fourth episode. Apart from osteoporosis and mild type 2 diabetes she has no significant medical history.

Investigations

VEMP testing in recurrent BPPV is most useful for identifying which underlying process?

• AUtricular dysfunction (utriculopathy)
• BSaccular dysfunction
• CEndolymphatic hydrops
• DDemyelination of the inferior vestibular nerve