A new PET radiotracer may bring the diagnosis of chronic traumatic encephalopathy (CTE) — today confirmed only after death — closer to living patients. A preliminary study presented at the Society of Nuclear Medicine and Molecular Imaging (SNMMI) meeting evaluated the tau protein tracer 18F-OXD-2314 in dynamic brain imaging and showed an uptake pattern consistent with the disease.
How the study was conducted
Researchers evaluated the utility of 18F-OXD-2314 in dynamic brain PET of three retired collision-sport athletes (mean age 61) suspected of CTE and seven healthy control participants (mean age 63). Lead author Isabelle Boileau, PhD, a senior scientist at the Centre for Addiction and Mental Health (CAMH) in Toronto and professor of psychiatry, pharmacology and toxicology at the University of Toronto, described intriguing findings.
“The signal wasn’t exactly what we’d expect, but we did find, interestingly, this very high signal at the junction between the white and the gray matter, which is, I think, typical of CTE. We also found quite a bit of binding in the white matter,” she explained. Boileau stressed the preliminary nature of the work and the need for more studies before any clinical application.
What CTE is and why imaging is so hard
Chronic traumatic encephalopathy is a neurodegenerative disease linked to repeated head impacts, common among collision-sport athletes. Its pathological hallmark is the abnormal buildup of tau protein in the brain. The core problem is that, until now, a definitive diagnosis has only been possible at post-mortem examination — there is no validated biomarker to confirm the disease in life, which limits both care and research.
This is where molecular imaging comes in. A PET tracer able to bind specifically to pathological tau could, in theory, reveal the protein’s distribution in the living brain. The pattern seen at the cortico-subcortical junction is precisely what the literature describes as characteristic of CTE, which makes the finding promising — even if it still needs confirmation.
Implications for clinical practice
If validated, 18F-OXD-2314 could change the management of patients living with symptoms attributed to CTE. “This would be a game changer, not only because it would help validate the suffering and the difficulties these people have in life, but also because, with advances in tau-targeting therapeutics, we might select people based on this imaging agent for participating in trials,” Boileau said.
For radiologists and nuclear medicine physicians, the message is clear: molecular neuroimaging is poised to act as a selection and response biomarker, a role similar to the one already discussed in AI-based mapping of cerebral blood flow and Alzheimer’s. Reading these exams will require standardized acquisition and interpretation, especially in dynamic PET, which is technically more demanding than conventional static PET.
Context: neuroimaging and the race for tau
Interest in tau tracers is not new — Alzheimer’s disease drove the development of several compounds. What is new here is the attempt to apply the technology to a condition where in-life diagnosis has always been an obstacle. The work aligns with the broader trend of bringing artificial intelligence and quantification into MRI and neuroimaging interpretation, where assisted reading helps standardize subtle findings. Crucially, a tracer that works for CTE would also sharpen the differential diagnosis with Alzheimer’s and other tauopathies, since the spatial pattern of tau deposition differs between these conditions — and that spatial signature is exactly what dynamic PET aims to capture.
CTE, sport and why it matters broadly
Although CTE gained notoriety in American football, it is a concern for any sport with repeated head impacts. Soccer, boxing, mixed martial arts and other contact sports expose athletes — professional and amateur — to the same risk of microtrauma accumulated over years. The absence of a test that can confirm the disease in life makes counseling these patients and deciding when to end a career far harder.
A validated imaging tool would have a direct impact on sports medicine and public health. It would let clinicians stratify risk, track progression and eventually offer therapies before symptoms become disabling. For nuclear medicine services, this reinforces the importance of following the development of these radiopharmaceuticals closely and preparing for quantitative brain PET protocols.
Limitations and next steps
The study is small — only three patients and seven controls — and the authors acknowledge they still need to understand whether the observed signal reflects CTE-related tau or another aspect of the disease not visible in the post-mortem brain. “We still need to figure that part out, and that’s, I guess, the exciting bit of being in research,” Boileau admitted. Next steps involve larger cohorts, comparison with established markers and clinical correlation. Even so, the result puts 18F-OXD-2314 on the radar as a possible tool to detect — and one day treat — a disease that today is confirmed only too late.
Source: Diagnostic Imaging
