A 58-year-old woman with no significant past medical history…
A 58-year-old woman with no significant past medical history presents with a 2-month history of recurrent brief episodes of vertigo. The episodes are usually provoked by particular head movements and occur a few times each day. They occur when the patient is getting up from or rolling over in bed. She denies any hearing loss, tinnitus, nausea, vomiting, fever, vision changes, or other neurologic complaints. The woman also denies any recent upper respiratory infection or trauma. Physical examination is within normal limits. The Dix-Hallpike maneuver provokes nystagmus and vertigo. What is the most likely diagnosis?