That's an excellent question. Thank you very much. It's one that all of us who are diagnosticians.... That's what I do in emergency medicine. I come in with someone who doesn't yet have a label, who says “I have this”, and we have to come up with that. It's an issue that we face every day on all of these diseases we see, including concussion.
I'm going to answer your question in two ways: first on what we can do now and, second, on what we can do in the future to help this.
On what we can do now, again, this is where it's so important that we have high-quality, evidence-informing guidelines that then get into the hands of the people who need to do this. As part of the Berlin, the Parachute or the pediatric-specific Ontario Neurotrauma Foundation guidelines, all of them have sections on how to make the diagnosis. As the speakers prior to our group alluded to, some of the roles sometimes are for people within their scope of practice to suspect concussion, and then some of this is to make the diagnosis.
I think that for some of the concussions, they're going to be clear. There is a definite concussion. There was a witnessed loss of consciousness. The brain was definitely involved.
In children—as a pediatrician, I see this all the time—what happens to that two-year-old or three-year-old who is skating for the first time, fell, hit their head and now has a goose egg? We know that they've hit their head, but did it affect their brain? Some of the tools we use are not necessarily valid in that age group. The communication skills may not be best in order for that child to even communicate. It's the same with the elderly.
I know that the goal for today is to focus on sport, but this certainly happens in.... I'm sure you watch sporting events on TV. There's a collision and a player goes down. From watching it on TV we know that the person hit their head, but did it affect their brain? That's what you need for concussion. It must be a brain injury. You don't always have to hit your head; the collision can be to elsewhere in the body and the energy can be transmitted in that whiplash-type motion.
With regard to that and saying that it is definite, possible or probable, these are all things you can think about, but in terms of a lack of better evidence to help us differentiate those, the management for concussion at this point is still the same. It's conservative, being to prevent, with no harm first, do no harm.... You don't want that person going back to an activity where they're going to reinjure themselves. I think the first and foremost thing, whether it's still possible or definite, is to make sure they do not engage in another risky behaviour within a period while the brain has not recovered, to prevent the tragic outcome of what happened to Rowan Stringer, as we discussed earlier. That's number one in the management.
With regard to further diagnosis and clarification, again, those are all things where there are concussion tools that exist, such as the CAT tool we talked about earlier on how to train. There are guidelines that these providers can use. Those are all things that we need to make sure are part of the regular maintenance of certification.
The second part of my answer, not to take up too much time, though, is that we still are lacking that objective biomarker. There is no blood test, no saliva test, no picture test or even no eye-tracking, pupil size or balance test. None exists yet that on its own can objectively diagnose concussion.
This is something that many people are desperate for, especially outside of sport, such as the military. There's a blast, someone is thrown and now they're having symptoms. Well, was it a concussion or is it PTSD? The symptoms are very overlapping with regard to that. That can happen in concussion. Children who had a bad collision and a bad concussion can still have symptoms months and weeks on. Again, which are from the concussion and which are the other types of related sequelae of having an injury?
One of the things we need is more research to find these objective biomarkers. I know that there is a global effort among many groups to come up with that blood test, picture or other sort of validated measure that can accurately distinguish those two groups. That's something where as scientists we have more work to do.