MINNEAPOLIS (WCCO) — Brain injuries are the No. 1 cause of death and disability in Americans under age 35, according to the U.S. Centers for Disease Control and Prevention.

Now, a new technology that looks at your eyes can help doctors diagnose brain injuries better than any other tool. WCCO’s Natalie Nyhus spoke with a neurosurgeon about how the test works.

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Concussions are a scary injury because what we see on the outside may not reflect what’s happening on the inside. Doctors have long been able to see how the brain looks.

Now, they can see how it’s working just by tracking eye movement.

“The underlying premise is that when normal people’s eyes are moving, if they are watching television for example, they move with really tight synchrony. When someone has a brain injury, their eyes do not move with tight synchrony. And we can measure that,” Dr. Uzma Samadani said. “We can figure out how badly the eyes are functioning. That tells us something about how well the brain is functioning.”

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Minnetonka High School Head Football Coach Dave Nelson makes concussion education and training a priority with his players and staff.

“Any new technology that we can have our players use to diagnose their situation is great. It makes it safer for the player’s return and gives us instant feedback,” Nelson said. “I think it’s awesome the new diagnostic methods that are coming out.”

Dr. Samadani said this technology could soon be used on the sidelines and that we can liken eye tracking and concussions to the way blood tests can diagnose a heart attack.

“We are going to change the way brain injury is diagnosed and defined,” Samadani said.

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Right now the technology has been tested to work as soon as two hours after an injury takes place, and sooner in the future. The goal is ultimately to be able to do this eye tracking on a smartphone or tablet using the forward-facing camera.