Internal globus pallidus deep brain stimulation (GPi DBS)
Information for patients and families
Some patients with dystonia benefit from a surgical treatment called globus pallidus deep
brain stimulation, or GPi DBS. However, the treatment is not for everyone. Your
symptoms, age, and your ability to come to the hospital frequently are some of the factors
that you and your doctor will consider before deciding if you might benefit from this
procedure. This sheet answers some of the most common questions about GPi DBS. After
reading the information, talk with your doctor. Together, you will decide if this treatment
may be right for you.
What is GPi DBS?
GPi DBS is a treatment that involves electrical stimulation of the brain. It is done in
several stages.
First, surgery is performed to place electrodes in
either one or both sides of the brain in a small
region called the internal globus pallidus (GPi).
After about one week, the patient returns to the
hospital to have one or two pulse generators, or
“pacemakers,” placed under the skin of the chest.
These devices are connected to the electrodes in
the brain. Several weeks later, the pulse generators
are turned on and begin to activate the electrodes
in the brain.
Who is a good candidate for GPi
DBS surgery?

Patients who have disabling
dystonia

Patients who have the DYT1
genetic mutation

Patients who are able to travel to
BIDMC for frequent follow-up
appointments for the first three
months after surgery
 Patients who are 16-75 years old
How does my doctor know if I will respond
to GPi DBS?
Although we cannot tell for sure who will or will
not respond, the treatment generally works best
for patients who have jerky movements associated with their dystonia. Other factors that
are considered in deciding who might be a candidate for this treatment are summarized
in the box.
What is the procedure like?
Before the surgery begins, you will have an MRI while wearing a head frame – a device
that helps your surgeon locate the target for surgery. The head frame will stay on
throughout the operation. The operation is done using strong sedatives given by vein. You
will be asleep for much of the surgery, but we will awaken you at times so we can judge
your response to brain stimulation. We may ask you to perform some simple tasks or
answer some questions. By using electrical recordings, in combination with your
responses, your surgeon locates (or “maps”) the exact area in your brain that needs
treatment. A permanent stimulating electrode is then placed in the globus pallidus. Most
patients have another electrode implanted on the other side of the brain. The surgery takes
about four to five hours. Throughout the procedure, you will be given medication to make
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sure you are not anxious or in pain. After surgery, your medication will be resumed and a
CT or MRI scan will be done. You will stay in the hospital for one or two nights. When
you go home, you will have the brain electrodes in place, but stimulation will not be turned
on.
About a week later, you will return to have a pulse generator implanted under the skin just
below the collarbone. This is the device that will deliver the stimulation to your brain. You
will be under general anesthesia while the device is being implanted; the procedure takes
one to two hours. (Patients having an electrode placed on both sides of the brain will have
two pulse generators.) The pulse generator will be connected to the brain electrode by an
extension wire running under the skin from the top of the head and behind the ear to the
pulse generator. You will go home on the same day, but your device will not yet be turned
on. Your first programming session – when your device will be activated – will be
scheduled for approximately three to four weeks after the pulse generator is implanted.
What follow-up care is required if I have this treatment?
It is important to understand that patients who have GPi DBS must make frequent visits to
the outpatient clinic during the first three months after surgery. These visits are needed so
that doctors can adjust the strength of the electrical stimulation your brain is receiving so
that it is just right for you. These changes are then matched with adjustments in your
medications until the right balance is achieved.
Frequent adjustments may be needed for up to three months. Over time, you may need
additional changes. If it is difficult for you to get to the hospital, this is something to
carefully consider before deciding to have the surgery.
Will I be able to feel the devices in my body?
You may notice small bumps on either side of your head at the surgical sites. The
stimulator pacemakers can be felt under the skin. A wire that connects the pacemaker in
the chest to the scalp can also be felt under the skin but is not visible. There is a small
amount of discomfort just after these devices are placed in your body, which is controlled
with mild pain medication. After a few days, there is no discomfort from either the brain
electrodes or the electrical devices in the chest.
When the electrodes are first activated or are being adjusted, you may feel a tingling or
pulling feeling in your legs, arms, or face. This sensation should subside within a few
moments. If not, the settings of your electrodes will be changed to correct the sensation.
Your electrodes continuously stimulate the targeted brain region; however once they are
turned on and set correctly, you should not feel anything.
If the treatment works, will I see an improvement right away? Will the
improvement last?
Some patients experience what we call a “honeymoon period” immediately following
surgery, even before the electrodes are turned on. This improvement is temporary, lasting
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only a few weeks. However, once the electrodes are turned on and adjusted properly,
symptoms will improve again. Remember, this process can take several months.
Unfortunately, we do not yet have a way to cure or stop the progression of dystonia. Even
if the treatment works well, you may continue to have good and bad days. Just as you have
ups and downs with medications, you will have ups and downs with the functioning of
your stimulator. We will work closely with you to help you get through rough periods if
your symptoms reappear or worsen.
Are there patients who should not receive this treatment?
This treatment is generally not offered if any of the following exist:
 significant dementia or confusion
 active psychiatric problem such as depression
 another significant brain disorder in addition to dystonia
 abnormal brain MRI
 a medical condition that makes general anesthesia unsafe
 a medical condition that requires body MRI on a regular basis
Are there risks associated with GPi DBS?
Any surgical procedure carries some risk, and this is also true of GPi DBS surgery. Your
overall health will be evaluated carefully before you are recommended for this surgery to
make sure the risk of problems is low. Fortunately, neurologic side effects of GPi DBS are
very uncommon. The most potentially serious side effect is bleeding in the part of the brain
where each electrode is inserted. Some bleeding in the brain occurs in 1-2% of procedures
in which a needle, wire, or electrode is passed through the brain. Fortunately, in the
majority of cases this bleeding does not cause problems. (Your doctor will talk with you
about stopping any blood-thinners or other medicine that would increase the risk of
bleeding.)
DBS hardware problems are possible months to years after the system has been installed.
These include breakage of the electrode wire under the skin in the scalp or neck and skin
infection or skin breakdown in the scalp. Many of these problems can be corrected without
removal or replacement of the brain electrode.
Having an MRI can damage the device or the tissues near it. If an MRI is needed, you need
to tell the radiology staff that you have a DBS in place. In some cases, patients may have
an MRI of the head if special precautions are taken. At present, MRI of other parts of the
body is not done in anyone who has a DBS. Other tests, such as CT (“CAT”) scans,
ultrasound, or x-ray can be done safely.
Also, diathermy (e.g., shortwave diathermy, microwave diathermy or therapeutic
ultrasound diathermy) – a special kind of heat treatment used to treat certain conditions –
cannot be done in someone with a DBS. The heat energy can be transferred through the
DBS system, which can cause tissue damage and can result in injury or death. If you have
surgery that will require the surgeon to use electrocautery to control bleeding, you will
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need to let your surgeon know that you have a DBS system. The DBS may need to be
turned off prior to your surgery.
Your neurologist and neurosurgeon will give you additional, detailed information about
possible complications and answer all your questions.
I think GPi DBS may be right for me. What happens next?
If you and your doctor decide that you might be a good candidate for this surgery, we will
ask you to meet with a number of specialists on our team and undergo a series of
examinations. This process will include:

Neuropsychological testing – You will meet with a neuropsychologist who
will administer tests to evaluate your thinking, your memory, and your
psychological health.

Meeting with the neurosurgeon - You will also meet with the neurosurgeon
who will perform the operation. You will undergo a complete examination and
have a chance to talk about any questions or concerns you may have about the
surgery. If needed, an MRI examination of the brain will be scheduled.
Once all these exams are complete, our team will look at the information and decide
whether or not to recommend surgery and how to proceed with your medication regimen.
If surgery is recommended, you will be scheduled for the procedure in about one to two
months. Once your surgery has been scheduled, you will be given more information about
coming to the hospital for routine pre-operative tests.
For more information on deep brain stimulation visit the websites below:
http://www.medtronic.com/your-health/dystonia/index.htm
http://www.wemove.org/
We hope you have found this information helpful. Please discuss this information with
members of your health care team. Ask any questions you have about this or any other
treatment you are receiving.
This material was prepared by clinicians from the department of neurology at Beth Israel Deaconess Medical Center. It is produced and
distributed by the Beth Israel Deaconess Learning Center. © 2009, Beth Israel Deaconess Medical Center. All rights reserved.
MC1682 10/09
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