Researchers say they have made significant progress toward being able to detect CTE (chronic traumatic encephalopathy) in the living, according to a UCLA study published Monday.
CTE, the degenerative brain condition diagnosed definitively to date only through autopsies, is linked by many scientists to depression and dementia and attributed to head trauma -- as in dozens of cases of deceased NFL players, including Hall of Famers Junior Seau and Mike Webster.
In the study published in the Proceedings of the National Academy of Science, UCLA reported finding signs of CTE, through PET (positron emission tomography) scans accompanied by other tests, in a total of 14 living former NFL players who had suffered concussions.
"Outside the Lines" reported in November 2013 that the research team had found signs of CTE in nine such former NFL players, including Hall of Famers Joe DeLamielleure and Tony Dorsett, All-Pros Mark Duper and Leonard Marshall, and five others who had been cited in a UCLA study published 10 months earlier.
Study co-author Dr. Julian Bailes, chairman of neurosurgery at the NorthShore Neurological Institute in Evanston, Illinois, said the patterns and locations of abnormal tau protein accumulations indicative of CTE in the brains of all 14 living ex-players are consistent with CTE diagnoses through autopsies. Deposits of tau are identified on the PET scans through the use of an injected chemical marker licensed to TauMark, a West Virginia company. It was invented by three UCLA scientists who co-authored the study.
Bailes said the marker's effectiveness in also detecting amyloid beta, a protein found in Alzheimer's disease patients as well as in some people with CTE, is advantageous for differentiating between the two conditions.
"We found that the imaging pattern in people with suspected CTE differs significantly from healthy volunteers and those with Alzheimer's dementia," Bailes said.
The study compared the results of the 14 former players with those of 28 healthy individuals and 24 of a similar age who have Alzheimer's, and found telling differences in the areas of the ex-players' brains that control mood, cognition and motor function.
Bailes, also a co-founder of the nonprofit Brain Injury Research Institute, told "Outside the Lines" that the study's expanded sample size and new comparisons rebut criticism of the UCLA group's approach leveled two years ago by some scientists who are developing other forms of testing for CTE in the living.
CTE is a condition with no known cure, but the UCLA study asserts that advances in identifying the brain disorder could yield progress toward treatments to delay its effects. The researchers identified four stages of CTE's development that, according to UCLA pharmacologist and co-author Dr. Vladimir Kepe, could lead to the ability to monitor the disease over time. Most of the retired players tested did not have signs of advanced CTE.
Bailes said he is confident that future stages planned for the group's research, including multisite studies and following subjects over time, will enable it to "continue to move the ball down the field."
Outside the Lines correspondent Steve Delsohn contributed to this report.