As reported on Wired.
BY SEAN CONBOY
A test developed at UCLA uses a PET scan to screen for chronic traumatic encephalopathy, a degenerative neurological disease that has been linked to repeated head trauma and until now could only be diagnosed posthumously. Several NFL players, including Junior Seau, who committed suicide in May and is shown here in 2007, have been diagnosed with CTE. Photo: Elise Amendola/Associated Press
It’s an old NFL maxim that a player’s legs are the first things to fail him. But it might actually be his brain. If a breakthrough in brain research stands up to empirical review, we may no longer have to wait until players like Dave Duerson and Junior Seau die to know if a lifetime of skull-rattling hits left them debilitated by dementia and depression.
A test developed by researchers at UCLA could use a routine PET scan to check players for evidence of chronic traumatic encephalopathy, a degenerative neurological disease that has been linked to repeated head trauma and until now could only be diagnosed posthumously. It would be difficult to overstate the importance of the test, detailed Tuesday in The American Journal of Geriatric Psychiatry. Just a few years from now, an NFL player in his prime could be shown a medical scan that spells the end of his career – not because of shredded knee ligaments, but because of the degradation of his brain.
“The implications for this could be enormous,” says Julian Bailes, the co-director of the NorthShore Neurological Institute in Evanston, Ill., and one of the lead researchers. “It could answer the question that a lot of players never thought to ask themselves — is it time to end a career before it’s too late?”
CTE lies at the heart of a crisis that’s been building within the NFL since 2002, when Steelers center Mike Webster died of a heart attack at the age of 50. An autopsy revealed a brain mottled by a protein called tau, which typically is found in those with Alzheimer’s disease. But Webster didn’t have Alzheimer’s. He had CTE.
The neurological disease, found in athletes who havesustained repetitive head trauma, is marked by progressive degeneration of brain tissue. Symptoms include memory loss, confusion, aggression, depression and eventually progressive dementia. A study by Boston University’s Center for the Study of Traumatic Encephalopathy posthumously diagnosed the disease in 34 of 35 professional football players studied, including stars Duerson, Seau, Cookie Gilchrist and John Mackey. Researchers have found CTE in high school players, suggesting it does not take a lifetime of hard blows on the field to irreversibly alter the brain.
Previously, CTE could be diagnosed only posthumously by staining cross-sections of brain tissue with an amino acid called AT8. Under microscopic evaluation, the stains reveal the distinct neurofibrillary tangles of tau. In this new study, by the Semel Institute for Neuroscience and Human Behavior at UCLA, five former NFL players were injected with a radioactive compound called FDDNP. The compound acts as a tracer by binding to the tau proteins associated with chronic traumatic encephalopathy. The tracer appears in varying densities — from blue (low) to red (high) — in a routine positron emission tomography scan.
The former players in the study ranged in age from 45 to 73 and had had sustained anywhere from two to 20 known concussions during their careers. When their PET scans were examined, all of them glowed red with high signals of CTE in the precise regions of the brain (amygdala and subcortical) where tau tangles were found in posthumous exams.
While the sample size is of the study is small, it has huge implications for professional and amateur sports, particularly football and hockey. Soon, routine brain scans for high-risk athletes could become just as common, and affordable, as cancer screenings. Athletes could be studied from cradle-to-grave, monitored for tau growth and corresponding neurological symptoms, something that was impossible before.
“The problem with diagnosing CTE posthumously is that we’re limited to a sample size of people who are clearly having serious neurological issues,” says Dr. Robert Cantu, chief of neurosurgery at Emerson Hospital and co-director of Boston University’s Center for the Study of Traumatic Encephalopathy. “What we need to clarify the scope of the problem is for seemingly healthy athletes to donate their brains as well.”
The new test could eliminate the response bias problem inherent to CTE studies and answer a myriad of previously murky questions, including whether the blows suffered in contact sports are killing brain cells and shortening life expectancy and, if so, how soon – and how rapidly – does the process occur? The test also could help settle the debate over whether CTE is exacerbated by a few major concussions or years of exposure to sub-concussive blows. And it could answer the most important question of all: How much tau is too much?
Image: Semel Institute for Neuroscience and Human Behavior
“One question that we might be able to answer in the future is what the burden of tau protein should be to be career ending,” Bailes says. “It’s possible that in a few years, the NFL could test every player in real-time for CTE in training camp.”
While the cost of the proprietary tracer, developed by UCLA, is not known, a PET scan costs about $3,000, according to Bailes, and takes just a few hours to administer and analyze. But the potential for diagnosing CTE in living athletes brings up an existential conundrum.
“It’s similar to the issues brought up by the human genome project,” Bailes says. “If you could find out that you have a very high propensity for cancer, would you really want to know?”
More pressingly, the breakthrough brings up not just a moral conundrum for the NFL, but a legal one as well. More than 4,000 former NFL players are suing the league for negligence over how the league dealt with traumatic brain injuries. Just last week NFL commissioner Roger Goodell told a panel, “[We] need to have a lot more research [into CTE] because there’s still unfortunately a lot of unknowns.”
Goodell might get his wish far sooner than he anticipated.
“When you can only find out if a person has a disease until after they’re dead, it’s natural to keep kicking the problem down the road,” Bailes says. “This is a game-changer.”
After decades of blissful ignorance, science might be on the verge of forcing athletes, from PeeWee players to professional superstars, to face something they’ve been conditioned to ignore: their own mortality. In the wake of Seau’s suicide, his close friend and former teammates, Marcellus Wiley, told ESPN that he wouldn’t want to know if he himself had CTE. “We saw how this ends,” Wiley said. “I just don’t want to write that narrative.” Such denialism, still so common among NFL players, assumes an inevitable fate. Bailes sees great hope in the possibility of real-time CTE monitoring, which remains at least a year away.
“Previously, we were only able to see the tragic endings,” Bailes says. “What if this let us discover that the tau burden could be reduced over time? What if these guys could walk away at the right time?”