Canadian scientists are attempting to become the first team in the world to diagnose chronic traumatic encephalopathy (CTE) in living patients, a breakthrough that could allow doctors to intervene before the devastating brain disease progresses. Currently, CTE can only be confirmed through postmortem brain examination, leaving people with suspected cases unable to access treatment or know their diagnosis while alive. A major research initiative at Toronto's Centre for Addiction and Mental Health is enrolling thousands of participants, including military veterans and athletes, to identify the disease's hallmarks through advanced brain imaging.

What Is CTE and Why Does It Matter?

Chronic traumatic encephalopathy is an incurable, degenerative brain disease that develops after repeated head trauma. It can emerge years after concussions from contact sports or exposure to bomb blasts. The condition affects the brain's structure and function, leading to a wide range of debilitating symptoms.

The possible symptoms of CTE include:

• Cognitive Effects: Memory loss, confusion, and ongoing cognitive decline that can mimic various forms of dementia
• Behavioral Changes: Mood swings, depression, anxiety, and suicidal thoughts
• Physical Symptoms: Balance issues, tremors, and movement problems
• Personality Shifts: Aggression, violence, and behavioral changes that can devastate relationships and careers

In worst-case scenarios, CTE progresses to a point where a person becomes a shell of their former self. The disease gained worldwide attention in the early 2000s after neuropathologist Dr. Bennet Omalu identified it in U.S. football player Mike Webster. Since then, hundreds of cases among professional athletes have been confirmed posthumously, including at least 18 former National Hockey League players and more than 340 former players from the National Football League.

Who Is at Risk for CTE?

While professional athletes dominate the headlines, researchers suspect that CTE affects far more people than the public realizes. Scientists have identified postmortem CTE cases among amateur athletes, homeless individuals, victims of domestic violence, and military service members. All these groups share a common risk factor: repeated head trauma.

Military personnel face a particularly unique risk. One 2022 study found evidence of CTE in four percent of samples from a brain bank featuring deceased U.S. service members, with higher risk among individuals who had also played contact sports. Researchers have discovered that CTE may develop in military members due to the rapid transmission of bomb sound waves through brain tissue, rather than any physical impact to the head. The accompanying winds can produce forces similar to multiple severe concussion-like impacts in a period of microseconds, causing the brain to rattle dangerously inside the skull and stretch and damage this complex organ.

How Are Canadian Researchers Trying to Diagnose CTE in Living Patients?

The research team at the Centre for Addiction and Mental Health is using advanced brain imaging technology, including high-resolution MRI scans, to identify the hallmarks of CTE in living people. Brendan Hynes, a former Canadian military veteran who spent 27 years exposed to bomb blasts, is one of thousands of participants in this groundbreaking study. Hynes suspects he has CTE after experiencing panic attacks, suicidal thoughts, and severe anger and depression that ended his military career.

"Our goal is to be the first lab in the world to image CTE and be able to diagnose it in life so that we can stop the disease and reverse it," said Neil Vasdev, director of the Brain Health Imaging Centre at the Centre for Addiction and Mental Health.

Neil Vasdev, Director of the Brain Health Imaging Centre at the Centre for Addiction and Mental Health

The research project is massive and years-long, with participants undergoing detailed brain scans and assessments. By studying the brains of living individuals with suspected CTE, researchers hope to identify specific imaging markers and patterns that distinguish the disease from other forms of dementia and neurological conditions.

Steps Researchers Are Taking to Advance CTE Diagnosis

• Advanced Imaging Technology: Using high-resolution MRI machines to visualize brain structure and identify changes associated with CTE in living patients
• Large-Scale Enrollment: Recruiting thousands of participants from high-risk groups, including military veterans, professional athletes, and amateur athletes with histories of repeated head trauma
• Longitudinal Tracking: Following participants over years to understand how CTE develops and progresses, allowing researchers to identify early warning signs
• Comparative Analysis: Studying living brains alongside postmortem data to validate imaging findings and establish diagnostic criteria

Why This Breakthrough Matters for Patients

For people like Brendan Hynes, the ability to diagnose CTE while alive could be transformative. Currently, families often discover a loved one had CTE only after death, following a tragic pattern: a former athlete or service member's life derails into substance abuse, gambling, violence, or bankruptcy. They die, often by suicide, far too young. Then a postmortem brain scan confirms what loved ones long suspected.

Hynes explained his personal motivation for participating in the research: "To me, it's even scarier than other forms of dementia or Alzheimer's. Lashing out? Violence? I don't want that to be me. I don't want to affect my family like that." A living diagnosis could allow patients to access support, make informed decisions about their care, and potentially benefit from future treatments designed to stop or reverse the disease.

Hynes

The recent death of hockey legend Claude Lemieux in May, who died by suicide at age 60, has renewed attention on CTE. His family donated his brain to Boston University's CTE Center for research, though researchers have not yet confirmed whether Lemieux had the disease prior to his death. Such high-profile cases underscore the urgent need for earlier detection and intervention.

If Canadian researchers succeed in developing a way to diagnose CTE in living patients, it could revolutionize treatment approaches and give hope to thousands of people currently living with undiagnosed disease.