Here’s What We Learned About Concussion Detection in 2015 (And What We Still Don’t Know)
Does playing football cause permanent brain damage? If it wasn’t already, that question is now squarely in the zeitgeist thanks to Hollywood and Will Smith.
The answer is not so straightforward, however. We are likely to learn a lot more about the subject in 2016 because so many labs are focused on concussion research right now. But scientists are only beginning to understand the details of how concussions—also a serious problem in the military—damage the brain. A better grasp of those details will help doctors get better at treating such injuries.
The past year featured dramatic announcements from scientists studying the relationship between concussions and brain damage. In September, researchers from the U.S Department of Veterans Affairs and Boston University announced that they’d found evidence of chronic traumatic encephalopathy, or CTE—a recently discovered neurodegenerative disease that impairs cognition—in the brain tissue of 87 out of 91 former NFL players they studied. In December, researchers conducting an extensive brain imaging study at Walter Reed National Military Medical Center revealed that they’d observed “brain scars” in advanced magnetic resonance imaging (MRI) exams of more than half of 834 soldiers who had been diagnosed with at least one mild traumatic brain injury, or concussion (see “Brain Scars Detected in Concussions”).
Findings like these deserve attention but should be taken with a grain of salt. Many of the former NFL players who donated their brains suspected they had a problem, so the results of that study don’t confirm the overall prevalence of the disease in football. And researchers don’t yet have enough data to understand the medical significance of the abnormalities revealed by the advanced MRI exams on soldiers.
There are crucial unanswered questions about how and why CTE arises. What are the most important risk factors for the disease? Are some people more prone to concussions, long-term damage, or both? Do specific kinds of trauma, or traumas to specific parts of the brain, carry more long-term risk? What exactly is at stake if a player or soldier returns to the field too early?
The good news is that funding for concussion-related research is surging, thanks in large part to the National Institutes of Health and the Department of Defense, and researchers will no doubt make progress toward answering those questions in 2016. And certain research efforts could soon lead to crucial new technologies for detecting and evaluating concussions.
Researchers are “on the cusp of a revolution” in which blood tests and new imaging techniques will make it possible to diagnose traumatic brain injury noninvasively, Ronald Hayes, cofounder and chief science officer of Banyan Biomarkers, told me earlier this year. Banyan, which is in the midst of a clinical trial involving 2,000 people, is seeking FDA approval of a blood test doctors could use to rule out the need for a CT scan, which exposes the patient to radiation. Hayes says the test could also potentially be used to diagnose concussions in the battlefield or on the sidelines (see “Two Companies Close in on a Concussion Blood Test”).
Meanwhile, researchers are scrambling to find new ways to detect concussion-related brain damage using advanced MRI and other imaging techniques. Recent results suggest that CT scans and conventional MRI exams could be missing clues that might help doctors better assess the severity of a brain injury and the risk of long-term complications. Gerard Riedy, a neuroradiologist at Walter Reed who is leading the largest-ever imaging study of traumatic brain injury in the military, says his group is on track to deliver recommendations on the use of advanced imaging techniques to the Defense Department by the fall of 2016. There are also large imaging studies going on in the civilian world, including a project at the University of California, San Francisco, that has enrolled 1,200 patients.
More detailed imaging data can be combined with blood test results and information about symptoms and long-term outcomes to help scientists develop a more quantitative understanding of the variations of concussion, the resulting symptoms, and the risk of lasting issues. Further down the road, doctors may be able to use some combination of blood tests and imaging to more precisely evaluate injuries and monitor recovery.
Finally, it’s worth asking: is a concussion pill a possibility? Just maybe. An experimental therapy reversed concussion-related brain damage in mice, according to a report Harvard scientists published in July (see “Will Football Players Someday Take a Concussion Pill?”). Kun Ping Lu, a professor of medicine who led the research, thinks the therapy, which is based on antibodies for a harmful protein that accumulates shortly after a concussion, could someday be turned into a drug for humans. In the near term, his group is pursuing a blood test.