An indiscriminate foe, stroke affects millions of people all around the world each year. In the United States alone, more than 5 million people have had a stroke, and half of these survivors retain physical limitations despite months or even years of physical therapy.
“Every neurologist knows we need better treatments and more options for patients who have survived a stroke but remain chronically disabled,” says Andre Machado, MD, PhD, Chairman of Cleveland Clinic’s Neurological Institute.
Dr. Machado is determined to help these patients by thinking beyond physical therapy. His plan, as outlined in his presentation at the International Leadership Board meeting in Greece last fall, is to target the underlying neurological roadblocks caused by stroke with a therapy called deep brain stimulation.
“The idea [for this research] came from the need,” says Dr. Machado, who holds the Charles and Christine Carroll Family Endowed Chair in Functional Neurosurgery.
“A patient of mine once challenged me by saying, ‘I didn’t come here just because I knew you’d provide me the best care today. I came because I expect you to be working on better treatments for tomorrow.’”
What is Deep Brain Stimulation?
Deep Brain Stimulation, or DBS, is a process by which doctors manipulate electric impulses within targeted areas of the brain. First, neurosurgeons place electrode leads into precisely targeted regions of the brain. They then implant a pulse-generating device into the chest. This device is connected to the brain via a long, thin wire that runs under the skin of the neck. By controlling the device, doctors can provide pulses of electrical stimulation to specific areas of the brain, directly manipulating networks of brain cells.
DBS primarily is used to suppress symptoms of movement disorders, such as the tremors associated with Parkinson’s disease. But Dr. Machado’s plans for DBS are very different. Instead of suppressing a movement abnormality, like a tremor, he wants to restore movement that has been lost on one side of the body.
“We are attempting for the first time to use DBS to help recover a function that’s been lost — i.e., motor function on the paretic side of a stroke survivor’s body,” Dr. Machado says.
In December 2016, a clinical trial to test this therapy in humans enrolled its first patient.
Novel Application for DBS
Dr. Machado has studied deep brain stimulation for many years along with his laboratory colleague, Kenneth Baker, PhD.
The most common type of stroke originates in the middle cerebral artery and damages one side of the cerebral cortex, which in turn causes paralysis on the other side of the body. Dr. Machado believes that by establishing new connections between the cerebellum and the cerebral cortex, a patient’s lost mobility can be regained.
The first clinical trial of DBS for stroke patients officially launched in December 2016, when the first patient received an implanted device that is not yet activated. Two months later, Dr. Machado reports that the patient is doing well, maintaining a schedule of physical therapy sessions twice a week. Once the device is activated, this routine will not change.
“Our goal is not to replace physical therapy, but increase its effectiveness,” explains Dr. Machado.
The trial is actively recruiting patients and will run for four to five years.
Eligible patients must:
- Have had a middle cerebral artery stroke 12-24 months ago
- Have completed a course of physical therapy
- Still suffer from severe, residual impaired movement on one side
Questions Dr. Machado hopes the trial will answer include:
- When is the best time to begin DBS treatment for optimal effectiveness?
- Who benefits the most from DBS? What characteristics identify a good candidate for this treatment?
Dr. Machado has a strategy for using the Neurological Institute’s philanthropic donations in the most effective way possible. By sponsoring research directly tied to external funding opportunities, he says, philanthropic money can launch major projects. The DBS study began with internal support and was then funded by NIH grants. Recently, the study was awarded a new multi-million-dollar grant via the National Institutes of Health’s (NIH) Brain Research through Advancing Innovative Neurotechnologies (BRAIN) initiative.
“We have demonstrated that we can seed a project with philanthropy, and then use that initial investment to catalyze discovery and further funding,” Dr. Machado says. “This study would never have gotten off the ground without philanthropic support. We want more stories like this.”
Dr. Machado credits the collaborative nature of research at Cleveland Clinic for making a study like his possible. His work in this area builds on a decade of laboratory research in partnership with fellow clinicians in the Neurological Institute and scientists in the Lerner Research Institute.
“DBS could represent a new avenue for improving long-term rehabilitative outcomes after a stroke,” Dr. Machado says.
Furthermore, if DBS proves effective for stroke patients, the door is open for future studies on other potential uses.
“The Neurological Institute is about ‘Excellence – Discovery – Innovation,’” Dr. Machado says. “We are not only committed to providing the most excellent care today. We are also discovering the neurological care of the future.”
For more insight on the study, watch our video interview with Dr. Machado.