The first person to receive deep brain stimulation (DBS) for stroke recovery is performing far better than her doctors anticipated.
Two years ago, Judy Slater, a 59 year old in Pulaski, Pennsylvania, was getting out of bed when she had a severe stroke. She fell down and couldn’t get back up; the stroke had left her entire left side paralyzed.
With time, Slater was able to regain her ability to walk, but her left arm remained almost entirely immobile, hanging against her side with her elbow stuck tightly at 90 degrees. Her hands and fingers had curled up, and she couldn’t extend them on her own. “I depended so much on my family,” says Slater, who lives with her husband and daughter.
Slater’s experience is not unique. In the United States, stroke is the leading cause of serious long-term disability among Americans, and about half of the 800,000 Americans who have a stroke every year end up disabled. With physical therapy, people can regain some motor function, but more than half of all people with stroke will continue to have severe movement impairments.
After the stroke, Slater couldn’t bathe or cook on her own, and she longed for her former independence. That’s why she agreed to become the first person in the world to receive deep brain stimulation (DBS) for stroke recovery: a procedure in which electrodes are implanted in the brain to provide small electric pulses. She is part of a new clinical trial at the Cleveland Clinic aimed at helping people disabled by stroke regain control of their movements.
A medical first
“Despite advances in physical therapy and acute treatment of stroke, there are still too many people who live with longterm disabilities, and new technologies are needed,” says trial leader Dr. Andre Machado, chairman of the Cleveland Clinic Neurological Institute.
Slater is the first person to receive the treatment. Machado and his team spent more than a decade testing DBS for stroke recovery in animals, and DBS has been used to treat tremors associated with Parkinson’s disease, but in that scenario, doctors are trying to get rid of tremors. In the case of stroke, Machado and his team are trying to make movement come back—a goal that’s considered harder to pull off.
In December 2016, Slater’s skull was opened and doctor’s surgically implanted electrodes in the area of her brain called the cerebellum. The electrodes provide small pulses that target damaged areas of the brain to help recover movement. The electrodes are attached to a wire that connects them to a small battery pack doctors surgically embedded under the skin in her chest. After she recovered from the initial surgery, Slater started physical therapy, and soon after that, her doctors turned on the device.
Four months after the electrodes were turned on, Slater is doing better than investigators expected. “Judy is performing exceptionally well,” says Machado. “Since we’ve turned on the device, we’ve seen an acceleration in her recovery, and we have not yet seen the limit of her gains.”
People with severe impairments from stroke can improve with physical therapy alone, but typically the gains are small and then plateau. Machado had originally hoped that Slater would experience improved movement beyond what was expected from physical therapy (DBS is not intended to replace physical therapy, but to make it work better). Machado expected the effects of DBS to eventually reach a similar plateau within about four months, at which point his team would measure how much the procedure contributed to her overall improvement.
But Slater has yet to stop improving.
“Week by week and month by month, we see improvements,” says Machado. “There is no flattening or tipping point. No one can predict where that point will be.”
Not only can Slater open up her left hand, but she can also move her wrist and elbow. She can open her purse, reach into her bag and grab what she needs. She can get dressed and do the dishes. “I am so excited I can move my fingers and my hand, and reach in front of me and to the side,” says Slater. “I can cook, cut vegetables and get dinner ready. It’s still a little bit hard, but I can do it.”
“What excites me is that we have reduced her dependence on other people,” says Machado. “She has exceeded my expectations, and this gives us courage to continue.”
An ethical dilemma
Slater’s case has been inspiring and an encouraging proof of concept study. But her results have put Machado in an ethical quandary. The study protocol states that Slater’s stimulation should be turned off now that she has used it for four months. That’s largely because no one—not Machado or the other doctors who advised his research team—thought she would improve beyond that time frame.
From a scientific standpoint, researchers including Machado want to turn off the device so they can learn whether a person keeps or loses the improvements they made with the brain stimulation. Scientists need to discover whether DBS for stroke is something a person uses for a few months, or if it’s a lifelong implant.
But Machado says he can’t bring himself to turn off Slater’s device—not yet, at least. “Judy took a risk by becoming the first person ever to have this surgery done,” he says. “Imagine you are in my shoes. Would you have the courage to turn it off? I’m an investigator and a physician, and the physician side of me wins—I will continue to treat her. No one has the heart to stop it.”
For now, Slater will continue her physical therapy with the device turned on, and Machado will work with the U.S. Food and Drug Administration—the agency that would eventually review the device for possible market approval—to change the study protocol. Cleveland Clinic has already enrolled the second patient into the clinical trial and implanted them with the electrodes; researchers will turn the device on after the patient recovers. They don’t plan to stop there: Researchers are currently screening more people to potentially enter the trial.
Slater says she is pleased to keep working with the device. “I’ve been thinking about what happens if they turn it off,” she says. “I don’t want to go back and start over where I was.”
“I am happy I did it,” she adds. “I still have a way to go, but I am going to get there.”