Bill Kochevar, who is paralyzed below his shoulders due to a bicycling accident eight years ago, is believed to be the first person with quadriplegia to have arm and hand movements restored with the help of two temporarily implanted technologies: a brain-computer interface (BCI) and functional electrical stimulation (FES). Using the technology, he can use a fork to feed himself and reach for a cup of water.
Kochevar, the first recipient of implanted brain-recording and muscle-stimulating systems, demonstrates his new ability. Photograph courtesy of CWRU.
The research with Kochevar is part of the ongoing BrainGate2 pilot clinical trial being conducted by a consortium of academic and U.S. Department of Veterans Affairs (VA) institutions assessing the safety and feasibility of the implanted BCI system in people with paralysis. The research is being led by Case Western Reserve University (CWRU), the Cleveland FES Center at the Louis Stokes Cleveland VA Medical Center, and University Hospitals (UH) Cleveland Medical Center. A study of the work was published in The Lancet on March 28.
Jonathan Miller, MD, assistant professor of neurosurgery at CWRU School of Medicine and director of the Functional and Restorative Neurosurgery Center at UH, led a team of surgeons who implanted two 96-channel electrode arrays on the surface of Kochevar’s motor cortex. The arrays record brain signals created when Kochevar imagines moving his own arm and hand. The BCI extracts information from the brain signals about his intended movements, which is then converted into patterns of electrical pulses by the FES system that Miller and his team implanted in the muscles of Kochevar’s upper and lower arm.
“For somebody who’s been injured eight years and couldn’t move, being able to move just that little bit is awesome to me,” said Kochevar, 56, of Cleveland. “It’s better than I thought it would be.”
To prepare him to use his arm again, Kochevar spent four months learning to use his brain signals to move a virtual-reality arm on a computer screen. Miller then led a team that implanted the FES systems’ 36 electrodes that animate muscles in the upper and lower arm.
The pulses sent through the FES electrodes trigger the muscles that control Kochevar’s hand, wrist, arm, elbow, and shoulder. To overcome gravity that would otherwise prevent him from raising his arm and reaching, Kochevar uses a mobile arm support, which is also under his brain’s control. Kochevar can make each joint in his right arm move individually. Or, just by thinking about a task such as feeding himself or getting a drink, the muscles are activated in a coordinated fashion. The BCI and FES system together represent early feasibility that gives the research team insights into the potential future benefit of the combined system.
“By taking the brain signals generated when Bill attempts to move, and using them to control the stimulation of his arm and hand, he was able to perform personal functions that were important to him,” said Bolu Ajiboye, PhD, assistant professor of biomedical engineering and lead study author.
Advances needed to make the combined technology usable outside of a lab are not far from reality, the researchers said. Work is under way to make the brain implant wireless, and the investigators are improving decoding and stimulation patterns needed to make movements more precise. Fully implantable FES systems have already been developed and are also being tested in separate clinical research.
Editor’s note: This story was adapted from materials provided by Case Western Reserve University.
