Brainwave scanner offers cheat-proof concussion test
Published Friday, October 7, 2011 11:57AM EDT
TORONTO - With the spotlight on concussion prevention as NHL teams officially take to the ice this week, Canadian researchers are unveiling a prototype brain-injury scanning device they hope will end up rinkside in coming seasons.
The Halifax Consciousness Scanner, developed by Mindful Scientific Inc. in conjunction with scientists at the National Research Council of Canada, analyzes brainwaves to determine whether a player has suffered a concussion from a fall or hit to the head.
But the device -- a miniaturized form of EEG, or electroencephalogram -- isn't intended only for NHL players, said Chris Barden, the company's chief operating officer.
The scan could be employed at the sidelines of any high-impact sporting event, whether the players are children, amateurs or pros, as well as in hospital emergency rooms or at the site of a car crash involving a suspected head injury, he said.
"Effectively, HCS acts as a kind of thermometer for brain status, so any situation where somebody might have suffered some kind of change in brain status could be a place where this would be useful," Barden said from Halifax.
"And particularly, we think in the area of concussion, this could be useful because we could deploy it to the site of injury -- to the hockey rink, to the soccer field, to airports -- basically any public space where someone might hit their head and would like to be checked out."
To measure brainwave activity, electrodes are placed on the person's head and various sounds are fed through earphones to elicit electrical activity in the brain. The scanner then analyzes brainwaves to determine whether they fall within normal parameters.
Co-inventor Dr. Donald Weaver, a neurologist at Dalhousie University in Halifax, said the auditory stimuli could include a nonsense sentence such as "this pizza is much too hot to sing," which the brains of people without a concussion or other brain damage "would recognize as unusual."
"And so if we had electrodes on your scalp, we would have picked up the signal where your brain went: 'What? That didn't make any sense,"' said Weaver, explaining that the device translates the brainwaves into a measure that shows how aware or conscious the person is.
The scanner can be used even when someone is unconscious, including in a long-standing coma, he said.
One advantage of the scanner is that it is cheat-proof, because it can't be manipulated as cognitive-behavioural tests for concussion can.
"Take a pro football player, for instance," said Weaver. "They know that if they get hit on the head, they're going to have conventional sorts of testing done on them to ascertain whether or not they have an injury.
"What some of these players do before the season begins and the baselines are being done, they don't do so well," he said of cognitive tests that are used as a basis for comparison after a head injury. "The baseline is already affected, so if they get hit, they're not so far off baseline.
"Whereas with this test, the brain's responses to sounds like "this pizza is too hot to sing," you can't fake your brain's responses to that. You've got no way of getting around this."
The company hopes to begin marketing a commercial version of the scanner to hospitals by next year, once it receives approval from Health Canada, followed by a more miniaturized device for sports teams and other public use in 2013. The company expects the latter product to retail for under $500.
"We're trying to make this user-friendly, so we don't want just wave patterns ... what we are aiming for is a red-light, amber-light, green-light system," said Weaver, noting that the test can be done in five minutes on the sidelines of a game to determine if a player can safely return to play.
With lights as indicators, the decision would be easy for lay people without specific medical training -- for instance, coaches of kids' teams, he said. "Red light, you're not going back out. Green light, you can go back out. Amber light is we need to watch you a bit longer."
Harry Zarins, executive director of the Brain Injury Association of Canada, welcomed the idea of an easy-to-use brain scanner.
"Certainly anything that could identify a concussion quicker is a positive step in terms of identifying a brain injury and dealing with it in the appropriate manner, " he said from Ottawa.
"I see a number of uses for it," including as a tool for paramedics at the site of a traffic accident or when a person has fallen or cracked their head on the street or in their home, Zarins said.
"This would be the first line of defence -- or offence -- in identifying a brain injury, and then it could be followed up with (other tests)."
Barden said scans have been done on about 100 subjects without a brain trauma to calibrate "normal" brainwave patterns, and studies are underway of people with various types of brain injuries for comparison.
The idea is not only to identify an athlete who has a concussion so the person's brain can take the time needed to heal, but also to prevent a second complicating concussion from occurring by avoiding a precipitous return to play on the ice or field.
"So instead of an individual saying, 'Yeah coach, I'm OK, I can go back out,' this would give a dispassionate verdict on that decision," said Weaver.
"So having a powerful tool, which is rapid and easy to use, will definitively be a game-changer in trying to change how we approach and think about concussion. It will let us identify people earlier and therefore get them out, so they don't do the dangerous repeat concussions."