New research presented at the annual meeting of the Radiological Society of North America suggests that some athletes who have experienced sports-related concussions still have reduced blood flow in certain areas of their brain even after clinical recovery.
We’ve talked about reducing concussions time and time again, but this study really brings new evidence to the equation. Concussions are commonplace in physical sports, and medical experts and team physicians use a series of neurological tests to help determine if an athlete has shown enough signs of recovery to return to athletic activity. The new findings suggest that the brain may not be fully healed, even if the athlete passes the standard neurological tests.
To learn more about blood flow to the brain, researchers from the Medical College of Wisconsin in Milwaukee analyzed concussion symptoms in football players who suffered a concussion using an advanced MRI technique. The MRI method explored blood flow in the brain as the concussion healed.
“This measurement of blood flow is fully noninvasive, without radiation exposure,” said study author Yang Wang, M.D., Ph.D., associate professor of radiology at the Medical College of Wisconsin. “We use arterial blood water as a contrast tracer to measure blood flow change, which is highly associated with brain function.”
Concussion Study
For the study, Dr. Wang and colleagues analyzed blood flow to the brain in 18 concussed players and 19 players without a concussion. MRIs were collected within 24 hours of injury and eight days after the initial injury, and the results were compared to those of non-concussed players. After looking at the results, researchers uncovered:
- Concussed players exhibited significant impairment during a clinical examination at 24 hours post-injury, but they returned to baseline levels at eight days post-injury.
- Interestingly, concussed players exhibited a significant blood flow decrease eight days after injury, while the non-concussed players had no change in cerebral blood flow at any point.
“In eight days, the concussed athletes showed clinical recovery,” Dr. Wang said. “However, MRI showed that even those in clinical recovery still had neurophysiological abnormalities. Neurons under such a state of physiologic stress function abnormally and may become more susceptible to second injury.”
Researchers are still trying to pinpoint why the reduction in cerebral blood flow occurred, but they believe the findings have important implications for determining when an athlete is ready to return to sport after a concussion.
“For years, we’ve relied on what athletes are telling us,” said Dr. Michael McCrea, professor of neurosurgery and neurology and director of brain injury research the Medical College of Wisconsin. “We need something more objective, and this technology may provide a greater measurement of recovery.”
Other co-authors on the study are Lindsay D. Nelson, Ph.D., Ashley A. LaRoche, Adam Y. Pfaller, B.S., Andrew S. Nencka, Ph.D., and Kevin M. Koch, Ph.D.
