73.1 F

Davis, California

Thursday, September 16, 2021

Conclusive concussions


UC Davis researcher seeks to make conclusive concussion tests available to all.

From breaking stories on Real Sports with Bryant Gumbel, to a 2015 feature film starring Will Smith, concussions have never had greater share of the limelight, even though diagnosing them is still subjective and ineffective. One man endeavors to change that.

Dr. Khizer Khaderi is a driven man, seeking to unite his personal background in technology and ophthalmology in a way to help athletes everywhere. Ophthalmology is the branch of medicine concerning the eye surgically, diagnostically and medically.

Khaderi and his team are developing a robust testing system that accurately determines whether a concussion has occurred. Khaderi is developing this system to be widely available, with current units being in the neighborhood of a couple hundred dollars. This test looks at three basic functions pertaining to the eye and the brain: eye movement tests, pupil dilation tests and a brain wave test.

“We look at four separate eye movements, then at the pupils as the fifth and EEGs [electroencephalogram] as the sixth,” Khaderi said.

The problems with current concussion tests are that they are subject to the player’s response and are easy to cheat.

AXON, the current system used nationwide, requires athletes to take cognitive tests beforehand to establish a baseline. These tests are easy to cheat on, as a player could intentionally perform poorly so that in the event of a concussion, their results would not appear that different. The tests are also highly subjective — the medical professional administering the tests after a suspected concussion event largely has to rely on player feedback regarding how that athlete is feeling.

Testing Eye Movements

The test uses an eye tracker while the patient looks at a screen. The tracker gauges the speed of the patient as they perform four different types of eye movements, with each movement being a different neural exercise.

“We started off with a literature review [to formulate the first tests],” Khaderi said. “We look at a normal distribution and one standard deviation of normality as a guideline for normal brain’s operation times.”

They found the average times the brain takes to complete basic tasks involved in directing the eye.

This means that Khaderi’s test does not need individualized baselines. Furthermore, the test is objective, in that it does not require athletes to assess their own state. Eye movements are controlled by the brain in a way that they cannot be realistically messed up; they only move so fast once the decision to move them has been made. Players cannot cheat.

If the results of the test are outside the parameters, or standard deviations, then a concussion is likely.

Proving Pupil Dilation

Another method of testing for concussions has been the use of light and pupil dilation. An unequal or lack of pupil dilation has been a common testing parameter, and are often the go-to tests because they show a large amount of information about what is going on inside the brain.

However, tests comprised of shining lights into the patient’s eyes are not wholly effective. Many factors could affect the test: time of day, presence of background light and the setting of the test to just name a few.

Khaderi has borrowed the principles in the psychology-backed International Affective Picture System (IAPS) to test pupil dilation. IAPS is based on the principle that the pupil will involuntarily respond to outside stimuli, such as viewing something pleasant or scary, and will not respond to something that has no cognitive implication.

As the pupil dilation results from psychological factors and not light changes, Khaderi’s test is objectively more precise at determining concussions. The test is comprised of showing pictures with targeted involuntary pupil responses to patients, and then using an eyetracker to measure if the pupils respond as they should. The prospective pleasant and scary images activate different parts of the brain, and are interspersed with neutral images to isolate dilation events during the test.

Failing to respond properly to the images indicates that the patient likely has a concussion.

Monitoring Brain Waves

The third test uses an electroencephalography (EEG) band. The band tests electrical activity of the brain and can classify the activity into various wavelengths. Khaderi looks specifically at the relative balance between two types of brain waves: alpha and theta waves.

A brain that is healthy and awake will typically put out more alpha brain waves than theta. Conversely, a brain that is in a dreamlike state, or one that has gone through recent trauma, will put out relatively more theta brainwaves.

Therefore, by using a noninvasive EEG headband, Khaderi and his team are hoping to be able to definitively say when concussion occurs.

The Bottom Line

“I was an ESPN Junkie. I’ve coached basketball back when I was younger,” Khaderi said about his motivation. “I wanted something for peewee leagues, middle schoolers or even younger.”

Seeking to consolidate his test into an easy to purchase and use system, Khaderi has shopped high and low for ways to bring his research to as widely an applicable area as possible. He is developing an application that can run on all tablets or computers in conjunction with an eye tracker and an EEG headband as part of a kit.

“When we first looked into eye trackers, Arrington Research had one for $1500,” Khaderi explained. “So I looked around and found the one we use now, on Kickstarter, from a company in Denmark.”

Khaderi’s current eyetracker costs around $100. In time, he sees these costs dropping.

“By the time this goes to market, technology will have surpassed it,” Khaderi said.

It is likely that these advances will make the technology itself cheaper, better and more readily available.

Currently, Khaderi’s test is in clinical trials with student-athletes at UC Davis.

The real issue of concussion is the danger of going back onto the field before the injury has healed. Theoretically, these tests will be able to plot out when the concussion occurred and would be able to detect concussion throughout the entire healing process. Furthermore, Khaderi would be able to use his test to determine if individuals have a history of traumatic brain injury as well.

“The human body is amazing at adapting,” Khaderi said.

Even with the ability to adapt and to heal, concussions are a very real threat to the mental health of any individual. Khaderi’s research aims to make them more diagnosable and preventable.

Written by: Aaron Sellers – sports@theaggie.org


Please enter your comment!
Please enter your name here