Various studies released this year have brought alarming news about sports and traumatic brain injuries (TBIs). I wrote about some of these, Treatment for Brain Injuries In Young Up 60% – Football, Bicycling, Soccer & Playground Lead Tally; Running Backs Hit Hardest & Linemen Hit More Often — New Study Sheds Light on Concussions; Concussions – What Parents Need to Know; and Detecting Concussion in Athletes on the Sideline Could Be a Lifesaver.
Now a new study from the University of Rochester Medical Center reveals that even routine head hits can cause injury. The research team focused on brain scans of high school football and hockey players. The scans showed subtle injury — even if the athletes did not suffer a concussion – after taking routine hits to the head during the normal course of play.
The research, reported online in the journal Magnetic Resonance Imaging, is preliminary, involving a small sample of athletes, but nonetheless raises powerful questions about the consequences of the mildest head injury among youths with developing brains, said lead author Jeffrey Bazarian, M.D., M.P.H., associate professor of Emergency Medicine at URMC with a special interest in sports concussions.
Bazarian and his colleagues analyzed before-and-after images of the players’ brains from diffusion tensor imaging (DTI). A DTI scan is similar to an MRI but it does not relay pictures, rather it captures and relays quantitative data that must be decoded and interpreted. The researchers detected small but noteworthy changes in the white matter of the teenagers.
“Although this was a very small study, if confirmed it could have broad implications for youth sports. The challenge is to determine whether a critical number of head hits exists above which this type of brain injury appears, and then to get players and coaches to agree to limit play when an athlete approached that number.” Jeffrey Bazarian, M.D., M.P.H.
Nine athletes and six people in a control group from Rochester, N.Y., volunteered to take part in the research during the 2006-2007 sports season. Among the nine athletes, only one was diagnosed with a sports-related concussion that season, but six others sustained many sub-concussive blows and showed abnormalities on their post-season DTI scans that were closer to the concussed brain than to the normal brains in the control group.
The URMC study is unique because it was able to compare brain scans from the same player, pre-season and post-season. Most other studies compare the injured brain of one person to the normal brain of another person from a control group.
Indeed, among athletes there is no easy, objective way to diagnose concussions. High schools, colleges, and professional programs routinely administer pre-season, computer-based cognitive tests. Yet some athletes have become adept at tricking the test, Bazarian said. They intentionally do poorly on the baseline so that a mild concussion will not show up if re-tested later.
Measurements in the study at hand showed many changes in the brain of the player with the diagnosed concussion; however an intermediate level of changes also occurred among the players who reported anywhere from 26 to 399 total sub-concussive blows. The fewest changes occurred in the control group, as expected.
Efforts to further understand the significance of study results are already underway. Bazarian and collaborators at the Rochester Center for Brain Imaging, the URMC Department of Emergency Medicine, Department of Athletics and Recreation, and the Department of Imaging Sciences, are working on an NFL-funded study of University of Rochester football players this fall. Ten players agreed to wear helmets with special sensors that objectively detect the number of head hits they sustain, the velocity and angle. Each player is also receiving a pre-season and 2 post-season DTI scans, and the data downloaded from the helmet sensors will be correlated with information from the images.
“Our studies are taking important steps toward personalized medicine for traumatic brain injury. In the future we’d like to be able to have a baseline image of a brain and clearly know the significance of changes that occur later.” Jeff Bazarian