What is deep brain stimulation?
Deep brain stimulation (DBS) is a surgical procedure that involves implanting electrodes in the brain, which deliver electrical impulses that block or change the abnormal activity that cause symptoms.
The deep brain stimulation system consists of four parts:
- Leads (thin insulated wires) that end in electrodes that are implanted in the brain
- A small pacemaker-like device, called a pulse generator, that creates the electrical pulses
- Extension leads that carry electrical pulses from the device and are attached to the leads implanted in the brain
- Hand-held programmer device that adjusts the device’s signals and can turn the device off and on.
In deep brain stimulation, electrodes are placed in the targeted areas of the brain. The electrodes are connected by wires to a type of pacemaker device (called an implantable pulse generator) placed under the skin of the chest below the collarbone.
Once activated, the pulse generator sends continuous electrical pulses to the target areas in the brain, modifying the abnormal activity in that area of the brain that is causing symptoms. The deep brain stimulation system operates much the same way as a pacemaker for the heart. In fact, deep brain stimulation is referred to as “the pacemaker for the brain.”
What kinds of neurologic conditions can be treated with deep brain stimulation?
Deep brain stimulation is approved by the Food and Drug Administration to treat a variety of movement and neurologic disorders including:
Deep brain stimulation is also being studied for use in the following conditions:
- Multiple sclerosis
- Chronic pain
- Traumatic brain injury
- Tourette syndrome
- Stroke recovery
- Thalamic pain syndrome
- Alzheimer’s disease
- Anorexia nervosa
Who is a candidate for deep brain stimulation surgery?
Before being considered a candidate for deep brain stimulation (DBS), patients must undergo an extensive evaluation process. Ideally, a multidisciplinary team of specialists including a neurologist, neurosurgeon, neuropsychologist and psychiatrist will assess the patient.
If patients are well managed on medications, DBS is not considered. Candidates for DBS are generally patients who meet these criteria:
- Symptoms are not well controlled despite receiving the appropriate dose of medications.
- Symptoms are significantly reducing a patient’s quality of life.
- Side effects from current medications cannot be tolerated.
How is deep brain stimulation performed?
Before the actual procedure begins, a head frame (stereotactic head frame) is positioned on your head, which will keep your head still during brain imaging. Surgical pins or screws are used to secure the frame to your head.
Your neurosurgeon will implant the deep brain stimulation system in two stages.
First, a small hole is made in the skull. The leads, which have electrodes at the ends, are passed through this hole and surgically implanted in the areas of the brain identified as the site(s) contributing to the symptoms.
A lead is positioned on one side of the brain unless symptoms occur on both sides of the body (then one lead is positioned on each side of the brain). Each side (hemisphere) of the brain controls the opposite side of the body, so each lead is inserted on the opposite side of where symptoms are occurring.
In a separate operation approximately 1 week later, one or two battery-powered pulse generator devices (one per lead) are implanted just under the skin in your upper chest area below your collarbone. An extension wire is attached to the lead already positioned in the brain, then tunneled under your skin behind your ear and down your neck to the pulse generator device.
You will return for an office visit about 2 to 4 weeks after the implant surgery. The implanted pulse generator is turned on by a hand-held device and the electrical pulses are adjusted until symptoms improve. (The device sends electric pulses to the brain through these leads.) The hand-held device can also check the battery level and can turn the device on and off.
Several follow-up programming visits will be needed to fine-tune the stimulation sent to the brain to best relieve symptoms. Then regularly scheduled longer-term follow-up visits will be needed to continue to check to make sure the system is working properly, adjust the stimulation as needed to continue to best control symptoms and to check the battery life of the device.
How does the neurosurgeon know where to place the electrodes in my brain?
Positioning the electrodes in the brain is the most critical step. The electrodes have to be placed in an exact location in the brain to improve symptoms. Computed tomography (CT) or magnetic resonance imaging (MRI) scans are taken before and/or during the procedure to pinpoint the exact areas to target and guide the lead and electrode placement. Many times an electrode may be used to record brain cells activity at the target site to improve lead placement.
Will I be asleep during the entire procedure?
You will be sedated or receive local anesthesia for part of the procedure, may or may not be awake for lead and electrode placement, and will be asleep when the impulse generator is implanted. To provide more details:
- A local anesthetic is applied to areas of the head where pins or screws are used to secure the head frame.
- You will be sedated during the beginning of the procedure, while the surgical team is opening the skin and drilling the opening in the skull for placement of the lead.
- Most patients will be awake for lead and electrode placement. This part of the procedure is not painful, as the brain does not feel pain. Being awake allows the surgical team to interact with you when testing the effects of the stimulation. However, some patients who cannot tolerate the procedure while awake can have the electrode and lead placed under general anesthesia. The lead placement is guided in real time by magnetic resonance imaging. The procedure is performed in a special MR-equipped operation room.
- Implantation of the pulse generator in the chest and connection of the leads from the device to the lead in the brain is usually done under general anesthesia.
Risks / Benefits
What are the advantages of deep brain stimulation (DBS)?
Deep brain stimulation (DBS) has many advantages:
- Unlike some other surgical options, DBS does not cause permanent damage in any part of the brain.
- The electrical stimulation is adjustable and reversible as the person's disease changes or his or her response to medications change.
- Because DBS is reversible and causes no permanent brain damage, use of innovative not-yet-available treatment options may be possible.
- The stimulator can also be turned off at any time if DBS is causing excessive side effects without any long-term consequences.
What are the risks and complications of deep brain stimulation (DBS)?
As with any surgical procedure, there are risks and complications. Complications of DBS fall into three categories: surgery complications, hardware (device and wires) complications, and stimulation-related complications.
- Surgical complications include brain hemorrhage, brain infection, wrong location (misplacement) of the DBS leads, and less than the best location (suboptimal placement) of the leads.
- Hardware complications include movement of the leads, lead failure, failure of any part of the DBS system, pain over the pulse generator device, battery failure, infection around the device and the device breaking through the skin as the thickness of skin and fat layer change as one ages.
- Stimulation-related complications occur in all patients during the device programming stage. Common side effects are unintended movements (dyskinesia), freezing (feet feel like they are stuck to the floor), worsening of balance and gait, speech disturbance, involuntary muscle contractions, numbness and tingling (paresthesia), and double vision (diplopia). These side effects are reversible when the device is adjusted.
How long does the battery in the impulse generator device last?
Batteries can last 3 to 5 years in non-rechargeable devices and up to 9 years in rechargeable battery devices. However, these times may vary significantly. A simple outpatient procedure is needed to replace the battery. Rechargeable battery devices can be charged daily (for about 30 minutes) or every 10 to 14 days (for about 4 hours). Your doctor will discuss how often you should recharge your battery based on your therapy settings.
Recovery and Outlook
How effective is deep brain stimulation?
In properly selected patients, DBS has been shown to be a remarkably safe and effective treatment for the conditions in which it has been approved. Although symptoms may not completely go away, they are significantly improved in most patients. Promising results have been seen in the conditions for which it is still under investigation.
There are advantages and benefits as well as risks and complications with all surgical procedures. You and your doctor will discuss this procedure as well as other treatment options to determine if deep brain stimulation is appropriate for you.
Does deep brain stimulation cure the diseases in which it is being used?
Deep brain stimulation does not cure the underlying disease. However, it may significantly improve symptoms, which improves a patient’s function and quality of life.
Will I still need to take medications after deep brain stimulation?
Yes. However, your dosage may be greatly reduced over time.
When will I be able to go home right away after the deep brain stimulation procedure?
The average hospital stay following implantation of the DBS leads is 1 to 2 days. Most patients are able to return home on the same day that their battery is placed.
How should I care for the surgical area once I am home?
- Your stitches or staples will be removed 10 to 14 days after surgery.
- Each of the 4 pin sites should be kept covered with band aids until they are dry. These should be changed every day as necessary.
- You will be able to wash your head with a damp cloth, avoiding the surgical area.
- You may only shampoo your hair the day after your stitches or staples are removed, but only very gently.
- You should not scratch or irritate the wound areas.
Will I have to limit my activity following deep brain stimulation surgery?
- You should not engage in light activities for 2 weeks after surgery. This includes housework and sexual activity.
- You should not engage in heavy activities for 4 to 6 weeks after surgery. This includes jogging, swimming, or any physical education classes. Anything strenuous should be avoided to allow your surgical wound to heal properly. If you have any questions about activities, call your doctor before performing them.
- You should not lift more than 5 lbs. for at least 2 weeks.
- You should not raise your arms above your shoulders or over bend or stretch your neck.
- Depending on the type of work you do, you may return to work within 4 to 6 weeks.
When to Call the Doctor
When would I need to call my doctor?
Call your doctor immediately if you experience any of the following symptoms:
- Severe and persistent headaches.
- Bleeding from your incision.
- Redness or increased swelling in the area of the incision.
- Loss of vision.
- A sudden change in vision.
- A persistent temperature of 101 degrees Fahrenheit or higher.
Can I use electrical devices?
While you should be able to use most electronic devices, you should be aware that:
- Some devices, such as theft detectors and screening devices, like those found in airports, department stores, and public libraries, can cause your neurotransmitter to switch on or off. Usually, this only causes an uncomfortable sensation. However, your symptoms could get worse suddenly. Always carry the identification card given to you. With this, you may request assistance to bypass those devices.
- You will be able to use home appliances, computers, and cell phones. They do not usually interfere with your implanted stimulator.
- You will be provided with a magnet to activate and deactivate your stimulator. This magnet may damage televisions, credit cards, and computer discs. Always keep it at least 1 foot away from these items.
Does insurance cover deep brain stimulation?
Most insurance companies are providing coverage for FDA-approved uses of deep brain stimulation.
It’s always best to contact your insurance representative directly to check the extent of coverage of deep brain stimulation for your medical condition.