What is deep brain stimulation (DBS?)
DBS is often described as a pacemaker for the brain. It works much like a pacemaker, sending electrical signals to the brain instead of the heart. It is primarily utilized for patients who have Parkinson’s disease, dystonia, or essential tremor (ET), and who can’t adequately control their disease with medication.
For those with Parkinson’s, DBS can reduce tremors and significantly improve slowness and stiffness; and make tremors disappear for those with ET. DBS can help relax muscles and improve abnormal postures caused by muscle contractions for those with dystonia. In all cases, DBS can help enhance quality of life.
It’s important to understand that DBS does not offer a cure for your disease, but a way to manage it more effectively. It can offer many benefits, including the need to take less medication and therefore experience fewer medication side effects.
When is a good time to consider DBS? Am I a good candidate?
There are somewhat different criteria for determining if DBS is a good option for you based on your diagnosis and condition. For Parkinson’s disease, DBS is typically helpful if you experience motor fluctuations or tremors that interfere with activities that are not already adequately managed by medication, are not improved by changes in medication, or you experience side effects that prevent you from taking higher doses. For ET, DBS may be considered if you have tremors that interfere with your quality of life and cannot be controlled adequately with medications. Other key factors considered are age in combination with general health, a solid support system of family and friends, absence of dementia or an active psychiatric illness such as severe depression, and realistic expectations for treatment outcomes.
Before any patient is considered for DBS surgery, they are evaluated by the U-M Surgical Therapies Improving Movement (STIM) multidisciplinary team, which has extensive training in DBS. The STIM team includes a neurosurgeon, neurologist, clinical neuropsychologist, speech pathologist, social worker, and other team members who ensure that you and your family understand the procedure and discuss your expectations and concerns.
What does DBS feel like when the device is on?
During the initial programming of the DBS, individuals may experience a slight, temporary shock or tingling as placement and levels are adjusted. Identifying the best placement and level enables you to receive the greatest benefit possible based on your unique condition and needs.
Most individuals feel little if any sensation at all during normal use. For the few that do, it is described as a slight tingling down an arm or leg, or mild facial pulling which subsides. This is more common in individuals using DBS for essential tremor as the device can be turned off at bedtime.
Does insurance cover the cost of deep brain stimulation (DBS)?
DBS is FDA-approved and covered by most health insurance companies. Some insurance companies require prior authorization before having surgery, and some do not fully understand DBS and may initially deny coverage. However, usually with some detailed explanation, the decision is reversed. Denial may be based on the false assumption that DBS is experimental. If your diagnosis is Parkinson’s disease, essential tremor, or dystonia, the proposed DBS surgery is approved by the FDA and is not experimental. If the DBS surgery is recommended for a different diagnosis, it may indeed be considered experimental and is at risk for denial of coverage. Experimental DBS surgery will require authorization/approval from your insurance company.
Does the DBS procedure need to be done with MRI? I have a pacemaker and cannot get an MRI.
The MRI provides the clearest and most detailed picture of the brain. This is the preferred method to make sure the best outcomes are achieved. However, DBS surgery can be performed using CT guidance. CT, or computed tomography, is a way of imaging the brain, but the detail in the pictures is not as good as with MRI. This may lead to suboptimal outcomes. CT-guided DBS is easier with ventralis intermedius (VIM) nucleus placement (done with essential tremor), as the VIM nucleus (a part of the thalamus section of the brain) is a bigger structure and not as deep. CT-guided DBS is much more technically difficult if the neurosurgeon is trying to place a lead in the subthalamic nucleus (STN), a part of the basal ganglia section of the brain, but it can be done. If you have a pacemaker, this will be discussed as part of your surgical planning.
Where would you put the DBS stimulator if I already have a pacemaker?
Pacemakers are typically placed in the same pocket in the chest where DBS stimulators are placed. Because pacemakers are placed on the left side of the chest, the DBS stimulator could be placed on the right side of the chest. Another alternative would be to place the DBS stimulator just under the skin of the abdomen. The extension wires from the leads to the stimulator would be longer, which would put it at higher risk for lead fracture, but there is generally more “padding” in the abdomen, so the stimulator does not stick out as much.
What if the stimulator battery runs out? What will happen?
It depends on what your symptoms are. If you have essential tremor, your tremor will not be controlled. While this is an annoyance, it is generally not considered an emergency, but you should contact your neurosurgeon or the STIM team to have the stimulator replaced as soon as possible. If you have Parkinson’s disease, the symptoms of tremor, slowness, and stiffness may come back in full force over a couple of days. In some cases, this can be an emergency because you may be unable to move. Most patients are on less Parkinson’s medications after DBS, so the amount you are taking is unlikely to help as much as prior to surgery. If the stimulator battery runs out, if you have Parkinson’s you should contact your neurosurgeon or the STIM team as soon as possible. They may tell you to go into the emergency room, and an urgent battery replacement will be scheduled. If you have dystonia, the symptoms of your dystonia may come back over days to weeks. Again, this will be more of an urgent issue, and you should contact the DBS neurosurgeon or STIM team as soon as possible. Following up with your DBS team for regular monitoring of your battery will greatly reduce the chances of your battery running out unexpectedly.
Will others be able to see my DBS device?
Once you are healed, there is very little evidence that can be seen. At some centers, a small amount of hair is shaved above your forehead on the top of your head at the time of Stage I. Most women and some men are able to style their hair in such a way that this is not very noticeable. However, if you have short hair, or no hair, the incisions are likely to be visible to others until you are healed. If your DBS center shaves the entire head, then the incisions will certainly be visible until they heal and your hair grows back. There will be a 2- to 4-inch incision in the scalp on the top of the head and a smaller incision behind the ear. Once healed, the incisions will leave scars that will be visible on balding heads but are well-covered when hair grows back.
The scalp will have bumps where the holes were drilled. The holes are filled with plastic caps that sit just under the scalp, leaving a small raised area. Again, in those with hair, this is not visible. In balding men, the raised areas on the scalp are more visible.
The extension wire that runs from the lead(s) in the brain to the stimulator is tunneled in the fatty tissue just under the skin. For most, the track of the extension wire is not visible. However, for those that are thin, it may appear as a large vein would, just under the skin.
The stimulator lies under the skin, just below the collar bone. Once healed, there will be a 3- to 5-inch scar from the incision. The stimulator site will be slightly raised. This is more noticeable in those that are thin. It may be noticeable if one is wearing a bathing suit or low cut blouse. However, this generally is not seen through clothing.
I live alone. Can I have DBS?
It depends on whether you have family or friends that are available to stay with you (or you with them) for a few days after surgery. You’ll also need help with transportation back and forth for your appointments as well as to and from the hospital. We have found that the outcomes from your DBS are better overall if you have someone helping you. If you have willing family and friends who are interested in helping you until you have recovered from your DBS surgery, you should be able to return to living alone.
I need tremor control in both of my hands to perform my job. Can I have DBS for both hands?
If you have Parkinson’s disease, you are likely to have bilateral surgery with placement of leads in the subthalamic nucleus (STN) or globus pallidus interna (GPi) and experience tremor control in both hands. If you have essential tremor (ET), lead placement occurs in the ventralis intermedius (VIM) nucleus of the thalamus, but often only on one side. This is done to see if there is enough benefit with tremor control in one hand. By doing so, the risk is cut in half. It has been our experience that most people can perform most of their activities with tremor control in one hand. If you find that you need both hands to be controlled, it is possible to place a DBS system for the other hand. Keep in mind, however, that those with bilateral VIM leads for ET often describe problems with speech and balance.
How do I know when to use my DBS?
Individuals with Parkinson’s disease or dystonia will be instructed to leave the stimulator on continuously. There is no need to turn off the stimulators, unless undergoing a medical procedure. Those with essential tremor who have leads placed in the ventralis intermedius (VIM) nucleus can turn the stimulator on or off, depending on when tremor control is needed. Many people turn the stimulator on in the morning upon waking and off at bedtime.
Can I do my own programming?
Finding the correct contact on your DBS lead can only be done by the DBS neurologist or nurse who does the initial programming. However, some of the newer stimulators on the market allow the DBS neurologist to set different programs. For example, they could set it so you would be able turn your stimulator voltage up to a pre-set level, or switch your settings back to the same settings you had at the previous visit.
I have essential tremor that affects my voice. Will DBS help the tremor in my voice?
Although DBS is excellent for helping the tremor that is experienced in the hands and arms due to essential tremor, it is unlikely that DBS will help your voice with just a unilateral lead. Although there may be patients who notice a slight improvement in voice with unilateral stimulation, most notice no improvement. With bilateral stimulation, the voice tremor may improve, but bilateral stimulation will often cause slurred speech as well. Botulinum toxin injections are generally more effective for voice tremor than DBS.
Why would you choose the subthalamic nucleus (STN) as a site for Parkinson’s disease? It seems that it is associated with more problems than the globus pallidus interna (GPi)?
In a recent large DBS trial comparing STN to GPi DBS for Parkinson’s disease, there was not much difference in the effect on motor symptoms. STN had a slight advantage in that people were able to reduce their medications more. In other studies, GPi is reported to have less depression and fewer problems with cognition after surgery, but in the large DBS trial, there really were not any clinically significant differences in outcome with respect to depression or cognition. The STIM team at our center implants leads in the STN for Parkinson’s disease. This is mostly due to training and comfort with the procedure.
What if something like stem cells is found to cure Parkinson’s disease in the next few years? Does undergoing DBS now prevent me from getting that treatment?
One of the advantages of DBS is that it is reversible. The stimulation can be turned off, and the hardware can even be taken out. Having DBS now should not prevent you from getting another treatment in the future if it turns out to be better. However, new treatments such as stem cell therapy will need to be tested in clinical trials before they are approved for use in humans. During the clinical testing phase, you may not be able to participate because clinical trials are often restrictive in their inclusion criteria and will not include people who have had DBS.
Chou, K, Grube, S, Patil, P. Deep Brain Stimulation. A New Life for People with Parkinson’s Dystonia, and Essential Tremor. New York: Demos Medical Publishing, 2012.
International Essential Tremor Foundation. (2010). ET vs. Parkinson’s: How do they differ? Retrieved January 15, 2015, from http://www.essentialtremor.org/wp-content/uploads/2013/07/ETvsPD092012.pdf National Institute of Neurological Disorders and Stroke. (July 24, 2014). Tremor Fact Sheet. My head shakes: is it dystonia? (2014).