Review Question - QID 213471

A 59-year-old man presents to the emergency department with a sudden-onset sensation that the room is spinning causing him to experience several episodes of nausea and vomiting. Upon arriving, the patient’s symptoms have resolved. He states his symptoms occurred as he was going to bed. He has never experienced this before, but felt extremely dizzy for roughly 3 minutes. He currently feels at his baseline. The patient is otherwise healthy and only has a history of eczema. His temperature is 97.7°F (36.5°C), blood pressure is 134/85 mmHg, pulse is 85/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam is notable for a healthy man with a normal gait. The patient has a physiologic nystagmus and his cranial nerve exam is unremarkable. The patient’s head is turned to the left and he is laid back on the stretcher, which exacerbates severe symptoms with a nystagmus notable. The patient’s symptoms improve after 2 minutes of being in this position. Which of the following is the most likely diagnosis?