The brain of deceased NHL enforcer Todd Ewen did not show signs of chronic traumatic encephalopathy despite suffering several concussions during the player's career, the Canadian Concussion Centre announced Tuesday.
A study of Ewen's brain didn't turn up any traces of CTE, a neurodegenerative brain disorder that has been linked to multiple concussions, the CCC said in a statement.
Ewen racked up 1,911 penalty minutes in 518 NHL games with St. Louis, Montreal, Anaheim and San Jose.
He died at age 49 on Sept. 19, reportedly of a self-inflicted gunshot.
The release said that while Ewen suffered from memory loss, chronic body pain, diabetes and depression prior to his death, his brain showed no sign of any neurodegenerative disease.
"We were very surprised by the results as we were sure Todd must have had CTE," Ewen's wife Kelli, who donated his brain to the study, said in the release. "We hope that anyone suffering from the effects of concussion takes heart that their symptoms are not an automatic diagnosis of CTE. Depression coupled with other disorders can have many of the same symptoms as CTE."
The CCC said it has analyzed 20 brains, with roughly half showing signs of CTE or the presence of another neurodegenerative disease.
"These results indicate that in some athletes, multiple concussions do not lead to the development of CTE," Dr. Lili-Naz Hazrati the neuropathologist who conducted the autopsy, said in the release. "Our findings continue to show that concussions can affect the brain in different ways. This underlines the need to not only continue this research, but also be cautious about drawing any definitive conclusions about CTE until we have more data."