You are an emergency medicine physician moonlighting as the doctor for a football team. An otherwise healthy teenager wearing a football helmet is tackled. He reports feeling dizzy and "slow" but denies headache, nausea, vomiting, balance problems, or incoordination. His vision is "slightly off." He has no numbness, tingling, or neck pain. On exam, he does not appear confused or uncoordinated. You test vestibular and oculomotor function and there are no noted deficits. He does have some inattention, deficits in recall, and concentration impairment, but he says this is due to being in the heat of the game. His sensory and motor exam are normal. Then, you retest vestibular and oculomotor function and he begins to feel nausea and more dizzy. He wants to return to the game and acts uncharacteristically irritable.
Challenge: What's your diagnosis? Should you send him to the emergency department? Can he return to the game?
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