A 55-year-old man presents with recurrent brief episodes of vertigo lasting less than one minute, triggered by rolling to the left in bed. The roll test shows ageotropic direction-changing horizontal nystagmus, stronger when the left ear is down. Which variant of BPPV does this indicate?

• A Posterior canal BPPV of the left ear (canalithiasis)
• B Horizontal canal BPPV of the left ear (canalithiasis)
• C Horizontal canal BPPV of the left ear (cupulolithiasis) ✓
• D Anterior canal BPPV of the right ear

Explanation

Ageotropic nystagmus (fast phase beating away from the ground) on the roll test with the stronger response on the affected side indicates cupulolithiasis of the horizontal canal. Canalithiasis produces geotropic nystagmus. The left ear is affected as nystagmus is stronger when the left ear is down. Posterior canal BPPV presents on Dix-Hallpike, not roll test.

Reference: Cummings Otolaryngology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.