Neurologist Develops Innovative Device to Treat Parkinson’s Disease

Keith Krehbiel has been living with Parkinson’s disease for nearly three decades. Although he was 42 years old when he was diagnosed with the neurodegenerative disorder, his Parkinson’s symptoms began when he was 40 years old. His symptoms were initially misdiagnosed as repetitive stress injury from computer use.

As the years passed and the disease progressed, it became more difficult for Krehbiel to move and walk, as well as do simple daily tasks, such as brewing a cup of coffee.

Krehbiel took high-dose medication, which caused severe nausea. But, when each dose wore off, he suffered from dyskinesia—involuntary, repetitive muscle movements. For Krehbiel, this meant bobbing and weaving his head.

“The symptoms were getting worse, and the side effects were almost unbearable,” Krehbiel told CBS News. “So, I viewed myself as reaching the point at which it was worthwhile to consider more dramatic alternatives.”

Krehbiel endured the symptoms of Parkinson’s disease until he enrolled in an international clinical trial that tested a new form of Deep Brain Stimulation (DBS), a technology first approved in 1997 by the U.S. Food and Drug Administration (FDA) to treat essential tremor and tremor associated with Parkinson’s disease.

In 2020, Krehbiel underwent surgery to implant the new adaptive Deep Brain Stimulation (aDBS) device. This type of therapy was previously available only on an experimental basis. Krehbiel, a political science professor emeritus at Stanford University’s Graduate School of Business, became the first person in the United States to receive aDBS therapy as part of regular care.

Krehbiel said he saw immediate results after the operation.

“Although my hands would shake a lot before, I could lift my hands up and hold them without trembling at all,” Krehbiel told CBS News. “And that was a phenomenal feeling.”

The surgery significantly improved his quality of life in other ways as well.

“I reduced my Parkinson’s meds by more than two-thirds,” Krehbiel, now 70, told Scientific American. “And I no longer have a sensation of a foggy brain, nor nausea or dyskinesia.”

Scientists consider aDBS technology a “game changer” for people with Parkinson’s disease. Just as a pacemaker responds to the rhythms of the heart, aDBS responds to an individual’s brain signals to control the electric pulses it delivers, according to Dr. Helen Bronte-Stewart, a professor of neurology and neurological sciences at Stanford University, whose research contributed to the development of aDBS.

“It’s like a pacemaker for the brain,” Dr. Bronte-Stewart, who served as the global principal investigator for the clinical trial, said in an interview for Stanford Medicine News. “The way a pacemaker in the heart provides electrical stimulation to keep the heart’s rhythm on track, deep-brain stimulation provides electrical stimulation to control the brain’s electrical rhythms.”

According to Stanford Medicine’s news article, DBS and aDBS technologies use electrodes connected to thin wires that are implanted into areas of the brain affected by Parkinson’s disease. The wires are attached to a small, battery-powered device implanted under the skin of the chest, similar to the placement of a cardiac pacemaker. The battery delivers trains of electric pulses through the wires and electrodes to the brain, disrupting signals that cause Parkinson’s movement symptoms, such as tremors and rigidity.

“Traditional DBS delivers constant stimulation, which doesn’t always match the fluctuating symptoms of Parkinson’s disease,” Dr. Todd Herrington, a neurologist, and director of the DBS program at Massachusetts General Hospital, who was involved in Krehbiel’s clinical trial, explained to the Scientific American.

According to Dr. Bronte-Stewart, the traditional DBS delivers a “one-size-fits-all” train of electric pulses to the brain continuously. The new aDBS, however, listens to brain activity and adjusts brain rhythms only when necessary, offering just the right amount of correction.
“This makes it more personalized, precise, and efficient than older DBS methods,” Dr. Bronte-Stewart said in the article for Stanford Medicine News.

What is Parkinson’s Disease?

An estimated one million people in the United States are living with Parkinson’s disease, a type of neurologic movement disorder that affects the brain and causes difficulty with movements or motor symptoms, according to the American Parkinson’s Disease Association (APDA).

“In Parkinson’s, brain circuits that coordinate movement begin to misfire, causing symptoms like tremors, stiffness, and slow movements,” Dr. Bronte-Stewart said. “One of the underlying causes is an abnormality in one type of electrical activity in the brain, called beta waves. Deep-brain stimulation sends an electrical signal that corrects the abnormal beta waves.”

A study published in February in The BMJ journal projected that 25 million people worldwide will be living with Parkinson’s disease by 2050, a 112 percent increase from 2021.

There is no cure for Parkinson’s. However, there are medications to treat Parkinson’s, and patients who are considered ideal candidates may receive DBS treatment.

Parkinson’s usually develops after 50, but younger people can develop the disease, too. This is referred to as Young Onset (or Early Onset) Parkinson’s disease. The APDA reports that approximately 10 percent of Parkinson’s diagnoses occur before age 50.

The most common motor and non-motor symptoms of the disease include:

Parkinson’s symptoms worsen over time and can impact the ability to perform daily activities.

More Patients to Benefit From aDBS

In February, the FDA approved the aDBS technology for market use to treat Parkinson’s disease. Medtronic, the Minneapolis-based medical device company that manufactures the aDBS technology, was excited about the FDA approval.

“Medtronic is the only company in the world to offer an adaptive DBS system that dynamically adjusts therapy in real-time,” Brett Wall, executive vice president and president of the Medtronic Neuroscience Portfolio, said in a news release. “This new era in Parkinson’s care represents more than a decade of intentional innovation—ushering in personalized neuromodulation at scale that responds to a patient’s changing needs, equipping clinicians with unparalleled insights, and setting a new standard for DBS therapy.”

Dr. Bronte-Stewart said the technology is suitable for anyone with Parkinson’s, not just those in clinical trials. Additionally, people in the United States with Parkinson’s disease who have a compatible DBS device can use aDBS. However, she cautioned that aDBS is not a cure, but only “a very effective therapy.”

Krehbiel still has Parkinson’s, but for now, it’s something that he can manage, thanks to aDBS, which has improved his quality of life. In the five years since he’s had the surgery, Krehbiel has become a grandfather, and he enjoys spending time with his grandchildren.

“I have three grandchildren under four years old,” Krehbiel told CBS News. “I think about what it’s like to spend time with them now and what it would have been like had I not had the operation. I think there’s a huge difference in my ability just to get around and enjoy them and the happiness I get from them.”

Source Links:

https://www.cbsnews.com/sanfrancisco/video/stanford-neurologist-develops-innovative-device-to-treat-parkinsons-disease/
https://med.stanford.edu/news/all-news/2025/02/deep-adaptive-brain-stimulation-parkinsons.html
https://www.scientificamerican.com/article/new-form-of-parkinsons-treatment-uses-real-time-deep-brain-stimulation/
https://www.apdaparkinson.org/what-is-parkinsons/
https://www.bmj.com/content/388/bmj-2024-080952
https://news.medtronic.com/2025-02-24-Medtronic-earns-U-S-FDA-approval-for-the-worlds-first-Adaptive-deep-brain-stimulation-system-for-people-with-Parkinsons