Deep brain stimulation (DBS) is a surgical procedure that can ease Parkinson’s symptoms, such as tremor, slowness, stiffness and dyskinesia, and decrease medication needs. Many people with Parkinson's wonder whether and when they should consider DBS. There is no strictly defined window of time during which someone can or should undergo DBS. And it’s not right for everyone, but in the ideal candidate, it can provide significant symptom relief.
The Basics of Deep Brain Stimulation
DBS delivers small pulses of electrical stimulation to specific areas of the brain to lessen Parkinson's symptoms. DBS systems have three main components:
- Lead: This is a wire surgically implanted into a brain area that is involved in controlling and coordinating movement. Electrical stimulation flows to the brain through the lead and one lead typically is placed in each side of the brain. (Some people only get one lead on one side.)
- Implantable pulse generator (IPG): Also called the neurostimulator, the IPG is the system's battery and "brains." A clinician programs the IPG to deliver the right amount of electrical stimulation for you and your symptoms. The IPG usually is surgically placed below the collarbone or in the abdomen.
- Extension wire: This connects the lead(s) to the IPG.
DBS was first approved by the U.S. Food and Drug Administration (FDA) for Parkinson's tremor in 1997 and then for other Parkinson's symptoms in 2002. Medtronic was first on the market and remained the only DBS device maker for over a decade until additional devices, including the Abbott St. Jude Infinity and Boston Scientific Vercise, gained approval in the last few years. This brought not only increased treatment options but also continued innovation.
Choosing a DBS System
Many people wonder what the differences are between these systems and which is best for them. All DBS devices have the same basic components and work the same way. But slight variations in the components, such as rechargeable batteries, and capabilities, such as the ability to deliver electrical stimulation in varied ways or record brain signals for possible correlation with symptoms, might lead your doctor and you to pick one over another. When thinking about DBS systems, consider:
- If you want a rechargeable battery
Rechargeable batteries (offered by Medtronic Activa and Boston Scientific Vercise) can last 15 to 25 years, which may mean fewer surgical procedures to replace them. Non-rechargeable batteries last, on average, three to five years. (Battery life depends on your device and individual settings.) But rechargeable batteries may require daily or weekly recharging. Some people don’t mind regular maintenance if it means fewer battery replacements, but others prefer an occasional battery replacement to regular upkeep.
- Whether you will need regular MRIs
All DBS devices are MRI "conditional," meaning that they are safe for MRI scans if certain conditions, such as using a specific type of MRI scanner with DBS off or programmed to different settings, are met. If you anticipate needing regular MRIs for an ongoing medical condition, ask if one device offers an advantage, such as compatibility with a broader range of MRI scanners or ease of the MRI safety approval process.
- How the surgical procedure will be performed
Surgeons traditionally implant brain leads while a person is awake so that they can be sure the leads are in the right spot and not causing side effects. But some centers do DBS under general anesthesia with MRI guidance. Choosing this "asleep DBS" could impact which device your doctor recommends or uses.
- What system your movement disorder specialist and surgeon prefer
Your personal physicians likely have more experience or comfort with certain devices. The ease of lead placement or ability to program in specific ways, for example, could direct them to suggest one device over another. Today's systems differ mainly in how the leads are built and deliver electrical stimulation to the brain and whether they have additional capabilities. Abbott and Vercise leads may allow more flexibility to potentially hone stimulation for better symptom control and less side effects. Medtronic’s Percept senses and records brain signals so that doctors may more precisely understand how a patient’s symptoms respond to DBS. Because the systems haven't been compared head-to-head in a clinical trial, it's unclear if one works better than another.
- Your level of interaction with the device
Some people want to change DBS settings (within certain parameters set by their physician) on their own. Others don't want to alter settings outside of doctor's visits. For those who adjust the device regularly, some programmers (such as the Abbott, which operates through Apple digital devices, or Medtronic Percept, which uses Samsung) may provide more comfort and familiarity. Percept also allows a person to track their symptoms and medications in an electronic diary for possible correlation with brain signals.
The Future of DBS
More DBS devices not only give more treatment options, they also spur competition and innovation. Researchers are working on the next generation of devices – adaptive or closed-loop DBS, which is personalized therapy. This type of device could adjust stimulation on its own in response to an individual's brain signals and symptoms. And while we work toward those upgrades, The Michael J. Fox Foundation is funding a DBS registry to collect information on all aspects of DBS: who gets which DBS system in what part of the brain for which symptoms, what settings they use, and how they do over time. This database will help direct doctors and patients to more informed decisions around who gets which DBS device when and how to program settings for the most benefit.