Parkinson's disease (PD) is a disorder of the brain that causes individuals to experience tremors and difficulty with walking, movement, and coordination. The disorder may affect one or both sides of the body. According to the National Institute of Neurological Disorders and Stroke, there is no cure for PD, but a variety of medications and therapies can provide dramatic relief from the symptoms. One such treatment is deep brain stimulation (DBS). DBS is a surgical procedure used to treat a variety of disabling neurological symptoms, but it's commonly used to treat PD patients. In 2002, DBS was FDA-approved to treat Parkinson's.
During DBS, a thin lead containing electrode contacts is implanted into a specific target area in the brain. The lead extends through a small opening in the skull below the skin and is connected to an extension wire with a connection behind the ear. The wire is connected to an impulse generator that is implanted under the skin just below the collarbone. Once the system is in place, electrical impulses are sent from the neurostimulator up along the extension wire and the lead and into the brain. These impulses block the electrical signals that cause PD symptoms. Programming of the stimulation is easy and painless using an external magnetic control box. The patient is left awake during the surgery (which typically lasts two to three hours). On average, the hospital stay is 24 hours. The stimulators are turned on for the first time three weeks after implantation. At present, DBS is used only for patients whose PD symptoms cannot be adequately controlled with medications. DBS specifically helps treat tremors, rigidity, stiffness, slowed movement, and walking problems. Although most patients still need to take medication after undergoing DBS, many experience a significant reduction of their PD symptoms and are able to reduce their medications. The amount of reduction varies from patient to patient. The reduction in dose of medication leads to a significant improvement in side effects such as dyskinesias (involuntary movements caused by long-term use of levodopa). In some cases, the stimulation itself can suppress dyskinesias without a reduction in medication.