A new adaptive deep brain stimulation method to treat the symptoms of Parkinson’s disease has been developed by scientists. In the new method, stimulation changes in real time, based on the patient’s neural signals, as compared to traditional deep brain stimulation, which is constant.
Deep brain stimulation (DBS) can be an effective treatment for Parkinson’s disease. But it has limitations that reduce effectiveness for individual patients, and prevents a more widespread use of the technique. For example, trained clinicians must program the implants. It can also be time consuming and, for some patients, satisfactory settings are never achieved.
“This is the first demonstration of adaptive DBS in PD using a fully implanted device and neural sensing. Our approach uses an algorithm to measure the patient’s neural feedback from the brain surface and change the stimulation in real time. This way, we avoid the stimulation being too intense when it is not needed, which can cause adverse effects such as involuntary movement, known as dyskinesia,"
said senior author Dr. Philip Starr, Professor of Neurological Surgery at the University of California, San Francisco.
Implanted Neural Prosthesis
To test their device, the researchers trialled it in two patients with Parkinson’s disease (PD). They used a fully implanted neural prosthesis designed to use brain sensing to control stimulation amplitude.
Co-author Professor Howard Chizeck, from the University of Washington, said:
“The device works by using a cortical narrowband gamma (60-90 Hz) oscillation related to dyskinesia to decrease stimulation voltage when gamma oscillatory activity is high (indicating dyskinesia) and increase stimulation voltage when it is low."
First author Dr. Nicole Swann, now at the University of Oregon, said:
“There are several reasons why adaptive DBS could improve this therapy. Reducing the stimulation current without losing the therapeutic benefit could reduce stimulation-induced adverse effects. It could also extend battery life, or allow the relatively large pulse generators we currently use to be made smaller."
Additionally, although present day open-loop continuous DBS has been demonstrated to be highly effective for PD in randomized clinical trials, a small number of PD patients fluctuate rapidly between extreme states of dyskinesia and bradykinesia, which makes them more difficult to treat. Adaptive DBS could prove very effective for them.
The work was supported by NIH grants, and the UC President’s Postdoctoral Fellowship.
Nicole C Swann et al 2018 Adaptive deep brain stimulation for Parkinson’s disease using motor cortex sensing J. Neural Eng. 15 046006