Portable concussion detector sends laser pulses through the forehead
As it stands, athletes suffering a suspected concussion undergo sideline tests and clinical exams by a medical professional who then determines the likelihood of injury, making it a matter of (educated) interpretation. So the search is very much on for technologies that can produce unequivocal evidence of concussion one way or the other. To this end, scientists at the University of Michigan have developed a device that can measure the well-being of brain cells by pulsing ultra-bright lasers through a patient’s forehead.
The pursuit of new technologies to more accurately diagnose concussion is one researchers are coming at from all angles, and with good reason. The risk of long-lasting impacts are seriously heightened when an athlete returns to the field having unwittingly endured a brain injury and goes on to receive further impacts. A quick and accurate detection method for light concussions without obvious symptoms would avoid these risks, and accelerate the patient’s recovery.
Over the years, researchers have produced some promising solutions. Tracking eye movements to see whether a patient can smoothly follow an on-screen subject, taking blood samples to search for key biomarkers, and seeing how patients respond to certain sound frequencies are just a few ways we might better detect concussions in the future.
The method put forward by the University of Michigan zeroes in on a key metabolic function in the brain driven by a molecule called cytochrome C oxidase, or CCO. The levels of this molecule decrease when brain cells are distressed, so by detecting its activity and how it is functioning, the researchers can tell if the brain tissue is metabolizing as a healthy brain would, or if it is suffering from an injury such as concussion.
The idea is to use infrared light, with certain wavelengths on the spectrum exciting a part of the CCO molecule, allowing scientists to observe its levels in the brain. This concept has been explored before using infrared lamps, but the signals tend to be noisy and unclear.
So, the University of Michigan scientists have dialed up the power of the light, instead using a laser that is almost 10 times stronger than the lamps used in previous experiments. This triggers a stronger response from the CCO molecule and allows the scientists to differentiate between its activity and other factors, such as the protein hemoglobin which responds to similar wavelengths of light.
The team packed this non-invasive technology into a portable device, which uses optical fibers to deliver pulses of infrared light to a subject’s forehead. It was then put to the test on participants who were made to perform a task designed to study attention. As they subjects worked through the exercises, the scientists used the device to observe an increase in oxygenated blood flow and oxygen consumption in the frontal lobe, a region associated with attention.
“This means that our new method can effectively measure brain metabolism, an index of brain function,” says associate professor of psychology Ioulia Kovelman.
With this proof-of-concept under their belts, the researchers believe the value of their new technology could extend beyond the world of sports to the assessment of other brain injuries, such as when a loss of blood pressure affects cell function in the brain. And because all types of cells rely on similar metabolic processes to function properly, it could also be used to assess other organs around the body.
"We think it can,” says co-author Rachel Russo. “We would have to adjust the depth of the measurement, but we may be able to observe other organs at risk of failure – for example, the heart, lungs or kidneys.”
The researchers are presenting their work today at the Photonics West conference in San Francisco and are seeking patent protection and partners to commercialize the technology.
Source: University of Michigan