SOUTH BEND, Ind. (CBS/AP) Notre Dame quarterback Dayne Crist is being hailed as a hard-headed hero after the 20-year-old brushed off a crushing helmet hit and led his team on a 71-yard scoring drive. He even pounded the last yard into the end zone himself.
Only after the score did he tell the team's doctors that the hit had blinded him in one eye and made him groggy.
"After I initially took the hit, I tried to shake it off," he said. "But then physically I could not see ... It was blurry to the point where I couldn't see anything out of my right eye."
That can be very dangerous, especially long term, says Dr. Ann McKee, associate professor of neuropathology at Boston University and a leading expert on traumatic brain injuries in sports.
"A concussion does not have to mean loss of consciousness. It could be seeing stars or momentary dizziness," she told CBS News. "Any individual who is suspected of having one should be removed from the game and not allowed to return" until a doctor says it is safe to play again.
Crist sat out the rest of the first half. Team doctors eventually said he did not have a concussion and cleared him to play after his vision cleared. In the second half, Crist led his team to another 17 points, although they lost the game.
Crist said Wednesday he's fully recovered and not worried about being hurt again. He said he is ready for Saturday night's game at Michigan State (2-0).
But McKee says it's exactly these kinds of hits that can lead to long-term brain injury.
"If they go back in when the concussion hasn't completely healed, they could have second impact syndrome. A handful of kids die every year from second impact syndrome," she says. "We found the beginnings of brain disease in high school players who had had three or four concussions. That makes us think that in some individuals it could start early in life - in high school and collegiate athletes."
Crist had a concussion in high school.
"The next thing I remember was waking up in bed the next morning, so I don't have a lot of recollection of that one," Crist said.
Just last month, a team of Boston researchers led by McKee, published a study which said athletes and soldiers found to have Lou Gehrig's disease might in fact be suffering from long-term effects of concussions and brain trauma.
Lou Gehrig's disease, also known as amyotrophic lateral sclerosis (ALS) is characterized by a long decline into full paralysis and eventually death.
The baseball player it is named after was famous for his on-field heroics in the face of serious injuries including concussions.
Let's hope Crist is not that type of hero.
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