In benign paroxysmal positional vertigo (BPPV) of the posterior semicircular canal, the Epley canalith repositioning manoeuvre works by:

• A Dissolving calcium carbonate crystals using the endolymph's buffering capacity
• B Fatiguing the vestibular hair cells through repeated stimulation
• C Repositioning the cupula through hydrostatic pressure changes in the endolymph
• D Sequentially rotating the head to guide otoconia from the posterior canal ampulla back to the utricle ✓

Explanation

The Epley (canalith repositioning) manoeuvre guides displaced calcium carbonate crystals (otoconia) from the posterior semicircular canal back into the utricle through a series of sequential head and body position changes. The four positions sequentially move the canaliths from the posterior canal through the common crus into the utricle, where they settle harmlessly. Success rate per treatment is approximately 80–90%. BPPV is caused by otoconia displaced from the utricle into the posterior semicircular canal (canalolithiasis), making the semicircular canal gravity-sensitive.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.