SAN FRANCISCO -- Dr. Mitch Berger, who serves on the NFL's head, neck and spine committee, said Thursday a blood test administered on the sideline during a game might diagnose a concussion.
He equated the test to how heart attacks can be diagnosed.
"There is one protein, UCH1, which is a neuronal marker and then there's glial fibrillary acidic protein, which is a glial marker that has been seen in blood in concussed individuals," Berger said following the panel entitled NFL Health & Safety Update And Interactive Head Health Technology Showcase.
"So, if we can do a blood test and rapidly, one of these companies is saying that they can actually do a test within two minutes, and if they can tell us that UCH1 is present ... then you can diagnose."
Berger spoke for more than 13 minutes to a group of reporters, addressing a range of topics from concussions to attempting to diagnose CTE before death.
"It's a pathological diagnosis so it's really a diagnosis that's made in autopsy so the goal would be to find an imaging modality," he said, adding that a PET scan has been somewhat successful in finding deposits of tau, the abnormal protein found in CTE victims, in the brain.
"I think it's important to keep in mind it is an entity that's pathologically made in autopsy; it can't be made ... during life," Berger said. "But I think in the future we'll get there with imaging, so I'm actually optimistic with what I see so far."
Berger said the number of players self-reporting concussion symptoms has led to a rise in reported concussions. Meanwhile, the league's decision to move the kickoff to the 35-yard line, resulting in fewer returns and, thus, fewer high-impact collisions, has led to a 40 percent drop in concussions on such plays.
Berger, who said he would work a sideline Sunday in Super Bowl 50 between the Denver Broncos and Carolina Panthers at Levi's Stadium, would not, though, say there was a direct link between CTE and football.
Mostly, he said, because tau deposits have also been found in the brains of people who did not have traumatic brain injuries. "We're obviously very concerned about this," Berger said.
"If we're going to find a link in football, we also have to find a link in the military population and the civilian population to put this whole story together. Remember, it's not just a pathological diagnosis; we have to move forward over time, we have to assess our players, we have to assess them as time goes on and really try to correlate the clinical findings with the eventual autopsy findings."
Still, many wonder, if certain people are indeed more predisposed to developing tau deposits and CTE, should they then stay away from a head injury-heavy sport like football?
Are some people more predisposed to such brain abnormalities?
"No more than I can say to an individual who says to me, 'My mother died of Alzheimer's disease. What do you think my risk is?'" Berger said.
"The science is just not there yet. We're going to get there, but we're not there yet."