Traumatic brain injuries are distressingly common among service personnel and have a strong connection with post-traumatic stress disorder. Berenice Baker finds out how REACT Neuro, a new virtual reality eye tracking solution, aims to assess cases and measure therapy progress with more precision.

Brain health AI company REACT Neuro has developed a virtual reality (VR) eye tracking solution in partnership with VR headset maker Pico Interactive to better diagnose TBI and track the progress of rehabilitation. It has commenced trials with Home Base, a programme that operates out of Massachusetts General Hospital, providing clinical care to veterans and service members with TBI and post-traumatic stress syndrome (PTSD).

Massachusetts General Hospital neurosurgeon Brian Nahed co-founded REACT Neuro with Shaun Patel and Rudy Tanzi with the joint aim of developing a quantitative measure of brain health.

“Initially our focus had been to better characterise concussions and to do so in an objective manner, and we created a pretty amazing tool,” Nahed says. “That led us on a path of realising that we not only were able to do this with brain health or concussions but, more importantly, with larger aspects of brain health and neurocognition.”

According to Nahed, interest in objective concussion diagnosis has grown dramatically in recent years, and international groups have defined a series of tests that together act as a net to capture people displaying any symptom. Not every concussion or brain injury is expressed the same way, either in the acute setting – right after it occurs – or in individuals with long-term problems.

“REACT uses high-speed camera detection of subtleties in not only the way you move your eyes, but the response to either light or certain impulses” he explains. “You can capture things that that you can't see with your own human eye, and you can quantify them, and that gives you an incredible insight into not only what's going on, but, frankly, what's not going on.”

The system enables clinicians to accurately and objectively measure improvement over time in a way that would be challenging using established methods and maintains consistency from first responders such as ambulance crew through to rehabilitation clinic. Nahed adds that the immersive aspect of VR that made it so attractive for gaming and other entertainment also takes the person being assessed out of a distracting environment, such as a sports sideline or a busy clinic, and allows them to focus.

Home Base is one of the medical practices working with REACT to trial the technology. It provides free care to post-9/11 veterans and active duty service members who suffer from what it calls the invisible wounds of war, including PTSD and TBI.

Director for brain health and traumatic brain injury services Alexis Iaccarino explains that eye tracking has been added to the assessment regime in the past five to ten years.

“We find that there could be some kind of subtle changes in visual motion in dynamic conditions; the ability to focus or react with the eye to things moving in your environment or as you move in your environment,” she says. “While we can do that using gross testing, such as following a finger or following a moving point in space, but VR, or goggle-based technologies, are much more precise and offer much greater data.”

Iaccarino says the REACT Neuro solution could be used in conjunction with Home Base’s other neurological and cognitive assessments and tools to help characterise the effects of head injury on service members.

“In the world of concussion, we see the chronic effects of these injuries,” she explains. “I don't think there's going to be one technology, or one exam tool, or one blood test that's going to tell the whole story. This injury is complex and it affects multiple systems; the visual system, the vestibular or inner ear balance system, cognitive function, and mood.

“We're going to need multidisciplinary assessments to really understand the full picture of any service member. But in the realm of vision, and the stimulator function, something like REACT could offer a very sensitive measure of function, and it's highly repeatable, meaning we can do it over again and compare results over time.”

Iaccarino’s team is conducting an open trial of the product with military service members who have experienced TBI and will collect data on people who were recently concussed and those who have had many injuries over a long career. They are looking to characterise their visual and vestibular ocular motor function and compare it to other measures of TBI and their history.

The solution was developed in partnership with VR technology solution specialist Pico Interactive, which had previously worked with Tobii, a company recognised as a world leader in eye-tracking technology.

Pico Interactive marketing director Logan Parr says: “The technology can break down barriers for people because you can use eye tracking to move around a screen and make selections within it. One of the side benefits of that is foveated rendering, which allows you to be able to create a high-resolution image exactly where the eyes are looking but use low resolution in the periphery of your eye, which enables developers to be able to create better-looking content on your VR headset.”

This ability to monitor exactly where a person is looking opens possibilities for a range of applications and has already been used extensively in training.

“One of the important goals of Pico Interactive as a company is working with partners such as REACT Neuro because these are the frontiers in the VR space and these are the people who are going to be making those differences,” explains Parr. “This is a classic example of that scenario where somebody is taking that technology and thinking through how we can tackle this with VR to change how people consider medical benefits.”

Iaccarino adds that TBI is pervasive in military service and tools like REACT Neuro are essential for assessing personnel from immediately after an injury occurs.

“Due to the nature of being deployed, it's very difficult to get care right away and so the effects of this injury can linger for people,” she says. “One of our main goals is to find the right tools to evaluate folks and give them the right treatments to get them feeling better.”

Nahed concludes: “For us, the ability to work with veterans, Veterans Affairs and the military is something that means a great deal to us as a company, not only because of the service that these incredible individuals have done for our country but, more importantly, because a lot of what we're trying to detect in anybody within the population is even more compounded.”