Deep brain stimulation (DBS) involves implanting electrodes within areas of the brain. The electrodes produce electrical impulses that affect brain activity to treat medical conditions. The electrical impulses also can affect cells and chemicals within the brain that cause medical conditions.

A pacemakerlike device controls the amount of electrical activity in deep brain stimulation. The device is placed under the skin in the upper chest. A wire that travels under the skin connects this device to the electrodes in the brain.

Deep brain stimulation is commonly used to treat a number of conditions, such as:

• Parkinson's disease.
• Essential tremor.
• Conditions that cause the muscles to contract, known as dystonia, such as Meige syndrome.
• Epilepsy.
• Tourette syndrome, which causes repetitive movements and sounds.
• Obsessive-compulsive disorder.

Deep brain stimulation also is being studied as a potential treatment for:

• Quick movements that look like exaggerated fidgeting, known as chorea, such as in Huntington's disease.
• Long-lasting pain.
• Cluster headache.
• Dementia.
• Depression.
• Addiction.
• Obesity.

Deep brain stimulation is an established treatment for people with movement disorders. These conditions include essential tremor, Parkinson's disease and dystonia. DBS also is used for psychiatric conditions such as obsessive-compulsive disorder and Tourette syndrome. And deep brain stimulation has been approved by the U.S. Food and Drug Administration to reduce seizures in hard-to-treat epilepsy.

Deep brain stimulation is used in people whose symptoms aren't controlled with medicines.

Deep brain stimulation is generally considered to be low risk. But any type of surgery can potentially cause complications. Also, using electrical impulses in the brain can cause side effects.

Surgery risks

Deep brain stimulation involves making small holes in the skull to implant the electrodes into brain tissue. The procedure also includes surgery to implant a pacemaker-like device under the skin in the chest. This device contains the batteries needed for deep brain stimulation. Complications of surgery may include:

• Misplacement of the wires with the electrodes, known as leads.
• Bleeding in the brain.
• Stroke.
• Infection.
• Trouble breathing.
• Nausea.
• Heart problems.
• Seizures.

Possible side effects after surgery

Side effects of deep brain stimulation may include:

• Seizures.
• Infection.
• Headache.
• Confusion and trouble concentrating.
• Stroke.
• Hardware complications, such as an eroded lead wire.
• Short-term pain and swelling at the implantation site.

A few weeks after the surgery, your health professional turns on the device. Then, you and your health professional work on finding the settings that work best for you. Some settings may cause side effects, but these often improve with further changes to the settings of your device.

There have been rare reports that deep brain stimulation affects the movements needed for swimming. Talk to a healthcare professional before planning to swim and make sure to take water safety precautions.

Possible side effects of deep brain stimulation

After the device is turned on, you might experience these side effects:

• Numbness or tingling.
• Muscle tightness of the face or arm.
• Trouble with speech.
• Trouble with balance.
• Lightheadedness.
• Vision changes, such as double vision.
• Mood changes, such as anger, mania and depression.

Deep brain stimulation is a serious procedure. If you're eligible for this therapy, weigh the risks and potential benefits with your healthcare team.

Before surgery, you'll likely need medical tests to make sure that deep brain stimulation is a safe and good option for you. You also may need brain-imaging studies, such as an MRI, before the surgery. These studies help map the areas of your brain where the electrodes are implanted.

Deep brain stimulation won't cure your condition, but it may help lessen your symptoms. While your symptoms may improve enough to make a difference, they often don't go away and you may need to continue taking medicines.

Deep brain stimulation isn't successful for everyone. Its success relies on several factors. Talk with a healthcare professional before surgery about what type of improvement you can expect.