Australian scientists hope a device about the size of a matchstick will one day help people with spinal cord injuries get back on their feet.
The device, a stent-electrode recording array or stentrode, could allow patients to control powered body armour, known as exoskeletons, or bionic limbs using only their thoughts, researchers announced Tuesday at the University of Melbourne.
The stentrode will be implanted in a blood vessel that sits over the brain, and will turn brain signals into electrical commands that could wirelessly move the exterior mechanical technology. Currently, most exoskeletons are controlled by a joystick that is operated manually.
A collaboration between the Royal Melbourne Hospital, the Florey Institute of Neuroscience and Mental Health and the University of Melbourne, the findings were published Tuesday in the journal, Nature Biotechnology.
Speaking at a press conference Tuesday, Thomas Oxley, a neurologist at the Royal Melbourne Hospital, said the project began when he had the idea that thought control of bionic limbs could be achieved without implanting a device through open brain surgery.
Preclinical studies have shown that by putting the stentrode in a blood vessel near the motor cortex, a key control centre for the brain, you can get the same recording as people previously obtained by surgically inserting something directly into the brain. He proposed that, using the stentrode, patients will one day be able to control mechanical limbs with their thoughts.
"The idea is the device is much less invasive than previous attempts at doing this and can be implanted longterm," said Terry O'Brien, head of medicine at the Departments of Medicine and Neurology, the Royal Melbourne Hospital and University of Melbourne. "There is no clinical device that does this at the moment."
It could also have applications far beyond assisting those with paralysis, he added. The stentrode could be used to record brain waves for those with conditions such as epilepsy, helping to predict when they are about to have an attack. "The applications are incredibly broad, and that's what makes it so exciting," O'Brien said.
The device, which has so far been tested on sheep, will undergo its first human trials in 2017. According to a statement from the University of Melbourne, patients will have to, in many ways, learn to walk and stand again by getting familiar with "coding" the signals to their exoskeleton. "With our device, you've essentially connected an electronic limb to the patient's brain, but they have to learn how to use it," Oxley said, according to the statement.
Nick Opie, a biomedical engineer at the University of Melbourne, told reporters the team hoped the cost of the device, after it has undergone human testing and is ready for market, would be similar to the cochlear implant — around A$15,000 (US$10,567) to A$20,000 (US$14,089). They predict it will be ready by 2022.
It is also hoped the stentrode will be as important to medicine as the cochlear implant, which was invented in Australia. "What cochlear implants have done for hearing, we want to do for mobility," Opie said.
Interest in bionic limb and exoskeleton technology has been developing rapidly in recent years. Earlier in February, SuitX announced a newPhoenix exoskeleton that aims to replicate human gait.