A 51-year-old man presented with progressive difficulty walking that developed over 1 month shortly after he ran a marathon. He frequently fell and had difficulty climbing the stairs. He stated he had hearing problems, but with further questioning, it was discovered he actually had difficulty deciphering speech. He did not have dizziness on standing nor bowel or bladder incontinence. He did not take medications, and he drank socially. He had no family history of imbalance problems. He still worked full-time as a lawyer.