Deep Brain Stimulation
Treatment Overview
Deep brain stimulation (DBS) uses electrical impulses to stimulate a target area in the brain. The stimulation affects movement by altering the activity in that area of the brain. The procedure does not destroy any brain tissue. And stimulation can be changed or stopped at any time.
Surgery is required to implant the equipment that produces the electrical stimulation. You are awake during the procedure (your scalp is numbed and you won't feel any pain), because you must work with the surgeon in placing the electrodes where they will have the most benefit. A small hole is drilled in your skull, and tiny wire electrodes are placed in your brain. A small battery-powered device (generator) similar to a pacemaker is implanted in your chest and connected to the electrodes in your brain by a wire. The procedure usually takes 3 to 4 hours, although it may take as long as 8 hours. The surgery may also be done in two steps where the electrodes are put in during one surgery and the control unit is connected and placed under the skin in a second surgery.
The device can be programmed so that it delivers the correct level of stimulation to provide the greatest relief of symptoms.
What To Expect
You will remain in the hospital for several days after the procedure while your doctor checks the effect of deep brain stimulation.
Why It Is Done
Deep brain stimulation may be used to relieve symptoms of Parkinson's disease, especially tremor, when they cannot be controlled with medicine. It is considered the surgical treatment of choice for Parkinson's disease, because it is more effective, safer, and less destructive to brain tissue than other surgical methods.
Deep brain stimulation of the thalamus is done to treat both disabling tremor caused by Parkinson's disease and essential tremor.
Procedures that stimulate the subthalamic nucleus and the globus pallidus are done to help control a wider range of symptoms (in addition to tremor) and are used more often than stimulation of the thalamus. Symptoms that are most often helped (besides tremor) include problems with changes between "on" and "off" time and dyskinesia. Symptoms that are less likely to get better include problems with walking, balance, and speech. In some cases, DBS can make these problems worse.
Deep brain stimulation may also be used to treat severe tremor related to multiple sclerosis (MS). Deep brain stimulation usually is a last resort after all other options have been tried without success to treat MS tremor. Only people with severe tremor are candidates.
How Well It Works
Deep brain stimulation of the thalamus is effective in reducing tremor. It does not affect slow movement (bradykinesia), stiffness (rigidity), or other symptoms.footnote 1
Compared to medicine for Parkinson's disease, DBS of either the subthalamic nucleus (STN) or globus pallidus (GPi) gave people almost 5 more hours of "on" time on average each day.footnote 2
Two studies comparing DBS of the STN to DBS of the GPi showed equal effects on the symptoms of Parkinson's disease after 2 and 3 years.footnote 3, footnote 4
- The group who had DBS of the STN was able to take less medicine for Parkinson's disease after 2 or 3 years compared to the group who had DBS of the GPi.
- After 2 years, the group who had DBS of the GPi had less depression and problems thinking than the group who had DBS of the STN. But after 3 years, there was no difference in depression between the two groups.
- Quality of life was similar between the two groups.
Risks
Risks of deep brain stimulation include:
- Infection or skin irritation caused by the device in the chest (stimulator) or by the wires or electrodes.
- Bleeding in the brain during the surgery, resulting in a stroke.
- Numbness, tingling, twitching, or other abnormal sensations when the device is turned on. (These usually do not last long and can be eliminated by adjusting the programming of the deep brain stimulation device.)
- Problems with the device, such as:
- A break in the wire leading from the electrode to the stimulator.
- Movement of the wires or the device under the skin.
- Need for a new battery for the device. A battery typically will last about 5 years.
- Failure or malfunction of the stimulator or the electrodes.
- Psychological problems, such as apathy and depression.
- Problems with thinking, memory, speech, or swallowing.
- Difficulty with walking or balance and an increased risk of falling.
- Seizures.
What To Think About
A neurologist with special training in Parkinson's disease is most often the best kind of doctor to make a decision about deep brain stimulation. If you might benefit from the operation, your neurologist can refer you to a brain surgeon with experience doing the surgery.
Deep brain stimulation may be considered as an addition to levodopa therapy, not a replacement for it. It does not cure Parkinson's disease and does not eliminate the need for medicine. The surgery can help maintain and extend the benefits of levodopa therapy. But it should not be considered for people with Parkinson's disease who also respond poorly to levodopa therapy.
Because of an increased risk of falling in people who have DBS, it's a good idea to understand the ways you can prevent falls after the surgery.
One of the possible advantages of deep brain stimulation over "lesional" surgery for Parkinson's disease (such as pallidotomy) is that it can be changed or reversed. The effects of lesional surgery, which involves creating a lesion or intentionally destroying a small portion of the brain, are permanent, but the electrodes used in deep brain stimulation can be adjusted, turned off, or removed if they cause problems.
Deep brain stimulation for tremor caused by multiple sclerosis (MS) is still experimental, expensive, and not widely available.
References
Citations
- Samii A, et al. (2004). Parkinson's disease. Lancet, 363(9423): 1783-1793.
- Weaver FM, et al. (2009). Bilateral deep brain stimulation vs best medical therapy for patients with advanced Parkinson disease. JAMA, 301(1): 63-73.
- Follett KA, et al. (2010). Pallidal versus subthalamic deep-brain stimulation for Parkinson's disease. New England Journal of Medicine, 362(22): 2077-2091.
- Weaver FM, et al. (2012). Randomized trial of deep brain stimulation for Parkinson disease: Thirty-six-month outcomes. Neurology, 79(1): 55-65.
Current as of: October 9, 2017
