A 54-year-old man comes to the office complaining of dizziness, along with a headache and a ringing sensation in his right ear. He says these symptoms began gradually about 3 weeks ago and have been progressively worsening. He describes the dizziness as a sensation that he is veering to one side, causing difficulty keeping his balance while walking and preventing him from riding his bicycle. The headache is mild, diffuse, and non-throbbing. He denies visual symptoms, or focal motor or sensory deficits. He has no nausea or vomiting. He was diagnosed with classical migraine 10 years ago and has been treated successfully with sumatriptan. He says he initially thought these symptoms were a migraine, but he usually has visual auras before his headaches and there were no visual disturbances with the current episodes. In addition, sumatriptan did not help, and he has not previously had tinnitus or vertigo with his headaches. He is uncertain about hearing loss, but he says, "My wife and daughter say I don't hear them when they are riding in the passenger seat of the car—which is not necessarily a bad thing."