The Epley canalith repositioning manoeuvre for posterior canal BPPV achieves its effect by:

• A Dissolving calcium carbonate canaliths through osmotic forces generated by sequential head positions
• B Converting canalithiasis to cupulolithiasis to allow natural resolution
• C Fatiguing the cupula response to canaliths by repeated stimulation
• D Gravitational migration of free-floating canaliths out of the posterior semicircular canal ampulla into the utricle through four sequential head positions ✓

Explanation

In posterior canal BPPV (canalithiasis), free-floating calcium carbonate debris displaced from the utricle lies in the posterior semicircular canal. Head movement causes these canaliths to move, creating abnormal endolymph flow, cupula deflection, and brief vertigo. The Epley manoeuvre uses four sequential head positions (starting with Dix-Hallpike to the affected side), each held ~30 seconds, to use GRAVITY to progressively guide the canaliths from the posterior canal ampulla, through the short arm, through the common crus, and into the utricle — where they dissolve or are reabsorbed. Success rate is ~80-90% in a single session.

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.