New implantable devices can treat a surprising range of neurological conditions
Pioneering research in neuromodulation at Toronto’s University Health Network is improving patients’ lives
Anne was an artist, but her degenerative nervous system condition, Parkinson's disease, made it impossible for her to steadily hold a paintbrush. To offer relief, her doctors at the University Health Network (UHN) in Toronto implanted electrodes in her brain. The electrodes connect to a pacemaker in her chest and a remote control, allowing Anne and her doctors to adjust the electrical stimulation of her nerves so the tremors and stiffness subside.
Called deep brain stimulation, this treatment has allowed Anne to paint again and hold her grandchild with steady hands. It's just one example of the kind of neuromodulation devices researchers are developing — devices that interface with the nervous system to change brain, spinal cord or nerve function.
It's estimated 3.6 million Canadians have some kind of neurological condition and 1.5 million more live with a brain injury. While we have medications to help such people, the emerging field of electroceuticals may offer even more hope.
The documentary I Am Human, presented by The Passionate Eye, explores the stories of Anne and two other pioneers who have received cutting-edge brain implants. Stephen, who has been blind since his mid-30s, now has some vision thanks to a surgical implant around his eye that both stimulates the retina and connects to a pair of external glasses. And Bill, who was paralyzed in a bike accident, received a brain implant that helped him regain some mobility.
Toronto a world leader in implants
UHN has been a world leader in neuromodulation devices for decades, pioneering studies in deep brain stimulation. "We have a long history in regards to doing clinical trials, and now we've moved to the creation of new devices," said Dr. Taufik Valiante, director of the Surgical Epilepsy Program and scientist at the Krembil Brain Institute.
Now, the UHN has founded the Center for Advancing Neurotechnological Innovation to Application (CRANIA). It is being built on a $16.5 million infrastructure grant from the Canada Foundation for Innovation, plus provincial and philanthropic funding, and will be in operation by 2023. The centre will include an operating suite specially equipped to do neuromodulation surgery and will run as a partnership with Krembil, the Toronto Rehabilitation Institute, and the faculties of applied science and engineering, medicine, dentistry, and arts and science at the University of Toronto.
"In the past, we were the end user of some of these devices that were made by industry," said Dr. Valiante, who is also co-founder of CRANIA. "Now, we want to be the place where we make the next generation of these devices."
New brain treatments
Dr. Valiante specializes in epilepsy treatment and surgery. "Epilepsy is like having a storm in the brain," he said. Brain surgery can remove or alter parts of the brain to reduce or eliminate seizures. He's developing a less invasive approach using an implantable device called a neural interface processor (NURIP). This is a computer chip that is implanted in the brain and detects when a seizure is about to happen and then delivers stimulation to stop it. The chip works with artificial intelligence, so the system learns over time when and where in the brain seizures often happen and how to best shut them down.
Another research project that falls within CRANIA's portfolio is developing new devices that stimulate the vagus nerve. An implant in the chest sends electrical pulses to the brain via the vagus nerve in the neck and is already used to reduce the number and duration of epilepsy seizures, but it can also help with other immunological conditions.
Some neurostimulation happens on a short-term basis, such as functional electrical stimulation. Used after a stroke, this therapy delivers electrical shocks to the affected muscles of a patient, making them more receptive to rehabilitation therapy. In fact, studies at UHN show this treatment improves recovery by 40 per cent.
Learning through implants
Dr. Valiante said part of the value of neuromodulation devices is the basic science data they can produce. "Not discussed enough with these implantable devices is the information we're able to take out from the brain to help teach us about the brain," he said. "The brain still remains a mystery."
For instance, at Toronto Western Hospital, there's an epilepsy monitoring unit that allows doctors to understand an individual patient's condition and also do research. Patients spend days there with electrodes attached to their brains to understand their epilepsy, but also these electrodes can collect data about which parts of the brain relate to memory. "What we found is a signal that's very specific to eye movement not only helps us explore the visual world, but is related to memory too," Valiante said.
An integrated approach
Innovation in neuromodulation is being driven by new advances in computation and engineering, as well as neuroscientists' better understanding of the brain and the nervous system.
These new implantable devices can treat a surprising range of conditions. Neuromodulation can impact mental health conditions such as anxiety, depression and obsessive compulsive disorder. Physically, the brain and nervous system is connected to gastrointestinal, urological and hormonal systems, and the treatment possibilities are there too. Said Dr. Valiante, "Literally, the nervous system is connected to everything."
For more, watch I Am Human on The Passionate Eye.