In April 2020, the Davis Phinney Foundation for Parkinson’s presented an online Deep Brain Stimulation (DBS) Forum. The webinar featured two movement disorder specialists, including Helen Bronte-Stewart, MD, MSE with Stanford, a couple of neurosurgeons, two people with Parkinson’s, and two scientists from device manufacturers. The speakers described DBS surgery, the best candidate, some limiting factors for qualifying as a candidate, current best practices, future improvements, programming considerations, the reduction of medications, and the efficacy of DBS as Parkinson’s progresses. We at the Stanford Parkinson’s Community Outreach listened to the webinar, and are sharing our notes.
The webinar was recorded and is available for viewing here.
If you have questions about the webinar, please contact the Davis Phinney Foundation for Parkinson’s tollfree at phone 866-358-0285, or send an email.
For additional resources on surgical treatment options for Parkinson’s and stories from those who have had the surgery, including materials to be reviewed online, ordered or downloaded, please see these pages on the Stanford Parkinson’s Community Outreach Program website:
Stanford hosts a quarterly DBS support group at the Stanford Neuroscience Health Center. If you live/work in the area and want to join us when we are meeting in-person again, please contact Steven Russell.
Now, on to our notes for the webinar.
– Steven
DBS Forum- Webinar Notes
Presented by the Davis Phinney Foundation for Parkinson’s
April 22, 2020
Summary by Steven Russell, Stanford Parkinson’s Community Outreach ProgramThe speakers included:
- Helen Bronte-Stewart, MD, MSE, Director, Stanford Movement Disorders Program
- Kelly Foote, MD, Neurological Surgery, University of Florida
- Aaron M. Haug, MD, Movement Disorder Specialist, Blue Sky Neurology
- Francisco Ponce, MD, Neurosurgeon, Director, Barrow Center for Neuromodulation
- Soania Mathur, MD, retired family physician, Person with Parkinson’s for more than twenty years
- Dr.Lisa Johanek, Senior Principal Medical Affairs Scientist, Medtronic
- Dr. Stephen Carcieri, Fellow Research Scientist, Boston Scientific
- Marty Acevedo, Person with Parkinson’s, DBS alumnus
The importance of DBS
Dr. Bronte-Stewart began with the basics of how deep brain stimulation (DBS) works and its importance as a treatment option for those living with a diagnosis of Parkinson’s. She considers the DBS stimulator to be a “brain pacemaker,” which helps to regulate the irregular brain wave patterns in one of several areas targeted in the brain that normally coordinate movement, executive function and more.
The best time for DBS surgery
Dr. Haug mentioned an important consideration — when is the best time to consider the surgery. Although DBS has been an approved treatment option for more than twenty years, until recently movement disorder centers reserved the procedure for those in later stages of the disease who were beginning to experience greater wearing off periods of their Parkinson’s medications or who were suffering side effects from the medications, especially dyskinesias. The Food and Drug Administration now considers the surgery appropriate for anyone having been diagnosed for at least four years and who is still receiving a strong benefit from Parkinson’s medications. Ms. Acevedo mentioned that she reached a point where managing her medications was becoming more challenging and, after her movement disorder specialist suggested that DBS might be a good option, did much research before beginning the testing process to qualify for surgery.
Who is a good candidate for DBS?
DBS can be beneficial for core motor symptoms (balance, tremor, stiffness), especially when the patient is receiving a good result from the Parkinson’s medications. DBS may also improve non-motor symptoms (some sleep disorders, gastrointestinal motility, freezing of gait, orthostatic hypotension, urinary dysfunction. Cognition and speech (especially clarity of speech) may decline with DBS surgery.
Dr. Foote listed three requirements for the best outcomes for possible surgical candidates
- Must have idiopathic PD.
- Must have a strong benefit from PD medications. A person is tested on/off medications to have a baseline. If there isn’t a strong response to PD medications, the person may not actually have PD.
- No other issues (co-morbidities) related to the surgery
Dr. Ponce stressed it is also important to help the candidate understand what can/cannot be improved with the surgery. Most of the patients he has met who were not satisfied with the results were not properly screened or helped to understand what the outcome for their individual case could be. Also important is how well the medications are helping with the most important symptoms to be treated with DBS. If the medications are providing little benefit, DBS will not be successful.Ms. Acevedo mentioned that she found the neuropsychological testing by far the most difficult part of the process.
Dr. Bronte-Stewart mentioned that Stanford looks for candidates where the PD medication has become both the patient’s friend (still good response and adequate “on” time) while beginning to become the patient’s enemy (more “off” time, dyskinesias becoming troublesome due to frequency and duration). Dr. Bronte-Stewart mentioned several studies that indicated DBS might be reducing the progression of the disease, although Dr. Foote thought the results were preliminary and not quite so definitive.
Dr. Foote also mentioned the “micro-lesioning” effect after any brain surgery whereby the surgical intervention itself can lead to patients reporting major improvement in their Parkinson’s symptoms even before the neurostimulator is activated.
Dr. Johanek and Dr. Carcieri reviewed the components and differences in programming abilities of the Medtronic and Boston Scientific devices. Except for Dr. Ponce, none of the other surgical centers had implanted an Abbott device. More and more surgeons and patients seem to be choosing a rechargeable battery (which can last three times as long as a replaceable battery)
Surgical considerations
Both Dr. Ponce and Dr. Foote said the pre-surgical process usually takes 4-6 weeks after the candidate begins the process. Dr. Foote mentioned that an important consideration is to have the surgery done at a center that has done many of these surgeries. He also mentioned he believes as the surgeon he provides just 25% of the benefit of the surgery (best placement for the symptoms). The remaining benefit comes from pre-surgical testing, patient expectation, and post-surgical programming.
Surgery is performed either awake (so the patient can respond to commands and demonstrate improvement during the surgery) or asleep (most patients prefer this). Be certain that the surgeon and center are comfortable with the option chosen by the candidate. Some centers do both.
There are some risks of the surgery:
- Failure to meet expectations-discussion needs to be open and honest about what the candidate and family expects and what the surgeon and his or her team believe can be accomplished. Set appropriate expectations.
- Despite being a major surgery, the risk of complications from DBS are quite small. There is a 1-2% risk of stroke or hemorrhaging or stroke and a slightly higher risk for infection.
- There may be a worsening of balance, swallowing, and cognition. Some risks can be mitigated by choosing a different target for the surgery and by post-surgical programming.
How is target chosen?
Dr. Foote and Dr. Ponce and their teams review symptoms (usually the top five) for desired improvement with the candidate and family. This helps to determine which target will provide the best benefit. The GPI (globus pallidus interna) is best for dyskinesias. Some centers implant in both sides (bi-lateral) of the brain while others focus on the dominant side affected by Parkinson’s. Some centers will implant bi-laterally but only stimulate one side (until the disease progresses to the other (non-dominant) side.
The importance of post-surgical programming
Ms. Acevedo mentioned she had a wonderful lesioning effect and that her stimulator was not turned on for more than two weeks after surgery. After the stimulator was activated she had no dyskinesia, no freezing of gait, her balance improved-she had been falling frequently before surgery, and felt that her cognition had also benefitted.
Dr. Foote and Dr. Ponce begin programming on the day the battery is implanted (this is an out-patient process) with “down and dirty” (standard) settings to be certain that the leads are properly placed and working. After a short period of recovery the patient returns for in-depth programming. Dr. Okun at the University of Florida tells his patients to expect at least six months of programming appointments before a good outcome and some equilibrium is achieved. Dr. Bronte-Stewart advises that Stanford waits longer before beginning programming, Stanford focuses on minimum (few benefits, no side effects) and maximum (great benefit, severe side effects) current settings which can provide a road map to be used in future, more precise programming.
Also important at all centers is the coordination of stimulator programming with Parkinson’s medications. Many DBS alumni can reduce or eliminate their Parkinson’s medications after surgery. Remember that Parkinson’s medications must be titrated down to avoid severe withdrawal symptoms.
There was a brief discussion about the results from DBS surgery for tremor, speech and cognitive issues. Proper targeting is imperative to improve these symptoms or to avoid a decline in abilities. Dr. Ponce mentioned that the new directional leads should help with the issue of stimulation bleeding beyond the targeted area to affect some of these symptoms.
Efficacy over time
Dr. Bronte-Stewart discussed the progression of Parkinson’s and how, as the disease progresses the dopaminergic and other systems may be affected. DBS will continue to provide benefit throughout the life of the patient, but the declines in these systems may exacerbate some symptoms. Programming and coordinating Parkinson’s medications are still very important at this time-particularly if it is determined after surgery that the lead placement was not ideal.
Other Considerations/Future of DBS
Dr. Johanek reminded the group that there are some restrictions for those who have had DBS surgery. She discussed MRI conditional safety (the center performing the MRI must know about the implanted device and follow the protocols from Medtronic or Boston Scientific to ensure patient safety). Dr. Carcieri mentioned that Boston Scientific’s focus is on newer techniques for directional steering of the stimulation as well as easier to use/understand programming devices. Both Medtronic and Boston Scientific are doing extensive research on software for better lead placement and programming.
Dr. Bronte-Stewart spoke of Stanford’s research on closed-loop DBS which can read brain rhythms and make adjustments to the stimulation being provided. Dr. Foote is also very excited to see adaptive DBS as an even more effective therapy. Dr. Ponce is hoping to encourage more people living with PD to become candidates for DBS as the benefits over time are better than remaining on medications alone. Ms. Acevedo would encourage those living with Parkinson’s and their care partners to learn as much as possible about DBS, consider it as a treatment option and to keep the lines of honest communication between patient, family, surgeon, and care team open and trusting.