Transcript for College Football Player Suffered From Brain Disease
And now to a story highlighting the risk of head injuries in sports. Doctors say they have found evidence a former college football player only 25 years old suffered from a degenerative brain disease. ABC's Ryan smith on why this case has researchers so troubled. I didn't know why all this was happening to him. Reporter: Cassandra knows how big hits in football can change lives. It hurt me to see him struggle so much. Reporter: Her husband Michael died two years ago at just 25 years old of a congenital heart ailment. Doctors announcing this week in a major journal that he suffered from cte. Chronic traumatic encephalopathy, a degenerative brain disease researchers say is connected to taking hits on the football field. Dr. Ann Mckie studied over 170 brains, including Michael's. When you see this disease in a person that young, it's surprising, even shocking. Reporter: Cte which is identified only after death has been found in numerous NFL players like hall-of-famers frank Gifford and junior sea, take a look at this video. A hit Michael told Cassandra was one of his hardest. He flies at an opponent, slamming into him. Colliding with such force parts of his helmet break off. I think he had way more than ten concussions. He was seeing stars and then he had sensitivity to light. All the time. He had a lot of anger and it was just impulsive. Reporter: They turned to doctors but Cassandra says test results came up empty. I was so mad that nobody could help him. It was just upsetting. He felt so alone. Reporter: She says Michael did not die in vain. Letting people know that this disease is out there. You don't know how many hits or how many concussions away you are from getting a disease like this, that's what is so scary. It could happen to anyone. Reporter: For "Good morning America," Ryan smith, ABC news, New York.
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