Stent-like device could help paralysis sufferers move their limbs
09 February 2016
A device the size of a matchstick, implanted next to the brain’s motor cortex, could one day help paralysed people move their limbs with the power of thought.
The key to returning mobility is a tiny, matchstick-sized device called a stentrode that will be implanted into a blood vessel next to the motor cortex, the brain’s control centre – bypassing the need for complex brain surgery. From there it will pick up brain signals and allow patients to move a robotic exoskeleton attached to their limbs simply by thinking about it.
This notion of wirelessly thought-controlled limbs is within reach, thanks to a collaboration of 39 individuals from 16 departments across the University of Melbourne’s medicine, science, veterinary science and engineering faculties.
A research paper published in Nature Biotechnology hails the pre-clinical animal trials of the stentrode, which measures only three millimetres wide, a success. The work is the result of close collaboration between the University of Melbourne, the Royal Melbourne Hospital and the Florey Institute of Neuroscience and Mental Health.
In late 2017, a select group of paralysed patients from the Royal Melbourne and Austin Hospitals in Australia will be chosen for the trial, where they will be implanted with the stentrode. If the trial succeeds, the researchers believe the technology could become commercially available in as little as six years.
The stentrode could also benefit people with Parkinson’s disease, motor neurone disease, obsessive compulsive disorder and depression and could even predict and manage seizures in epileptic patients. It is made from the alloy nitinol, and is designed to be inserted into the blood vessel with a catheter fed up through the groin – the same approach that has been used for years by cardiologists.
When the catheter is inserted into the blood vessel in the brain, it leaves a small cigar-shaped ‘basket’, wired with electrodes, which can record brainwave activity. Each of these electrodes records electrical activity fired by some 10,000 neurons, which is delivered via delicate wires that run out of the brain, into the neck and emerge into the chest into a wireless transmission system. The researchers say this transmission can be coded into signals to control an exoskeleton.
The first patient will need to work hard to ‘code’ each of these unique signals to their exoskeleton. The researchers believe the process will take many months before the movement becomes as effortless as driving a car, touch-typing, or writing.
The work was funded by DARPA, the Australian National Health and Medical Research Council, the US Department of Defense, US Office of Naval Research Global, the Australian Defence Health Foundation, and the Australian Brain Foundation.
YouTube video courtesy of Paul Burston and Sarah Fisher.