WASHINGTON, D.C.—The diagnosis and management of concussion continues to be an evolving and controversial subject in 2017, according to Andrew D. Perron, MD, FACEP, residency program director and emergency physician at the Maine Medical Center in Portland. While there is a growing body of evidence to support treatment guidelines, there continues to be conflicting information in key areas.

Concussion is a complex problem that is not well understood. Although there is currently a lot of attention focused on chronic traumatic encephalopathy (CTE), Dr. Perron stresses that the relationship between the two is not linear. Current literature supports a cascading model of events that occur within the brain after blunt trauma, including a decrease in blood flow to the injured area; cerebrovascular autodysregulation; tissue ischemia and edema; release of excitatory neurotransmitters such as acetylcholine, glutamate, aspartate; and the generation of free radicals.

Brains are individual and dynamic, and there is little predictability to the sequence and severity of signs and symptoms post injury, according to Dr. Perron. There are confounding factors that may need to be taken into account, including sleep deprivation, dehydration, and fatigue. In general, it appears that 90 percent of high school athletes with a sports-related concussion will be symptom free and can return to play within one month. Risk factors for longer recovery include multiple prior concussions, history of migraines and/or learning disabilities, and degree and severity of symptoms after concussion. Female sex may also play a role.

Dr. Perron stresses the need to use standardized tools during a sideline assessment of a player. “We are not good at just going to talk to [a player] and finding out what we need to know to decide whether they have a concussion or not,” he said. While not perfect, checklists such as SCAT3, Child-SCAT3 and the Concussion Recognition Tool make concussion assessment more consistent. Anterograde and retrograde amnesia seem to be critical markers of concussion.

Players who exhibit signs of concussion are removed from play immediately, and do not return to play on the same day. In all 50 states, there are laws in place that support this practice. Players must be monitored regularly to detect any change in status post injury. There is currently little evidence regarding the usefulness of concussion imaging. CT and MRI imaging can only rule out other brain injuries. Functional MRI (fMRI), eiffusion tensor imaging, and PET-CT may be helpful, but that is not yet clear.