AKT-1577

A 50-year-old woman comes to her GP complaining of recurrent vertigo that has been going on for 6 months. She reports experiencing episodes that last from a few minutes to several hours, accompanied by tinnitus and decreased hearing in her left ear. She denies any identifiable triggers that worsen her symptoms. She has no significant medical history. Her ear and cranial nerve examinations are normal.

What is the probable diagnosis?