TORONTO – The Krembil Neuroscience Centre's Canadian Concussion Centre (CCC) announces that the analysis of the brain of former NHL player Todd Ewen did not show signs of chronic traumatic encephalopathy (CTE) – a neurodegenerative brain disorder that has been linked to multiple concussions.
"These results indicate that in some athletes, multiple concussions do not lead to the development of CTE," said Dr. Lili-Naz Hazrati, a neuropathologist with the CCC research team who conducted the autopsy. "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."
Ewen was a 49-year-old retired professional hockey player who played for several teams in the NHL and sustained multiple concussions during his professional and amateur career. Although he suffered from memory loss, chronic body pain, diabetes and undiagnosed depression prior to his death – some symptoms which are known to result from having sustained repeated head injury – his brain showed no sign of CTE or any other neurodegenerative disease.
"Every time it was announced that a fellow player had CTE, Todd would say: 'If they had CTE, I know I have CTE.' He was terrified by the thought of a future living with a degenerative disease that could rob him of his quality of life, and cause him to be a burden to his family," says Kelli Ewen, Todd's widow who donated her husband's brain to the CCC for analysis.
"We were very surprised by the results as we were sure Todd must have had CTE," adds Mrs. Ewen. "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 results support the need for more concussion research to determine the prevalence of CTE in the brains of former athletes. The Ewen analysis brings the total of brains analyzed to 20, with roughly half showing signs of CTE or the presence of another neurodegenerative disease.
"Although it is encouraging to see that not all athletes who sustain concussions will develop CTE, we still need to better understand this disease and the effects of concussions on the brain in order to figure out how to identify those who will develop CTE as well as help people like Todd Ewen who struggle with symptoms from head injuries," says Dr. Carmela Tartaglia, a neurologist with the KNC's Memory Clinic who is also a member of the CCC research team. "We are very grateful to the Ewen family for making this important contribution to research as it's through these analyses that we hope to find answers."
The CCC aims to recruit a total of 50 brain donations to its ongoing research project and welcomes the commitment of donation from current or former professional athletes. All donor information is kept private, except when the player or family consents to release their name.
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The CCC, founded by Dr. Charles Tator, is one of few research projects in the world to examine the entire spectrum of concussion disorders from acute injury to chronic illness including brain degeneration. The team harnesses the expertise of several scientists and clinicians in brain injuries, imaging, genetics, neuropsychology and clinical care at the Krembil Neuroscience Centre and other brain research facilities to further our understanding of this common brain injury.
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Alexa Giorgi Senior Public Affairs Advisor Krembil Neuroscience Centre, Toronto Western HospitalPhone: 416 603 5800 ext 6776 Email: firstname.lastname@example.org
About Krembil Neuroscience Centre The Krembil Neuroscience Centre (KNC), located at Toronto Western Hospital, is home to one of the largest combined clinical and research neurological facilities in North America. Since opening in 2001, KNC has been recognized as a world leader through its research achievements, education and exemplary patient care. The centre focuses on the advancement, detection and treatment of neurological diseases and specializes in movement disorders, dementias, stroke, spinal cord injury, blinding eye diseases, epilepsy and cancer-related conditions.
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University Health Network consists of Toronto General and Toronto Western Hospitals, the Princess Margaret Cancer Centre, Toronto Rehabilitation Institute, and The Michener Institute of Education at UHN. The scope of research and complexity of cases at University Health Network has made it a national and international source for discovery, education and patient care. It has the largest hospital-based research program in Canada, with major research in cardiology, transplantation, neurosciences, oncology, surgical innovation, infectious diseases, genomic medicine and rehabilitation medicine. University Health Network is a research hospital affiliated with the University of Toronto.