Deep Brain Stimulation
The DBS system consists of three components:
- The lead (also called an electrode) is a thin, insulated wire inserted through a small opening in the skull and implanted in the brain.
- The extension is an insulated wire that is passed under the skin of the head, neck, and shoulder, connecting the lead to the internal pulse generator (IPG).
- The IPG or neurostimulator is the third component and is usually implanted under the skin near the collarbone. In some cases it may be implanted in the chest or under the skin over the abdomen.
A small opening is made in the skull under a local anesthetic. The patient is awake during the DBS surgery to allow the surgical team to assess his or her brain functions. While the lead (electrode) is being advanced through the brain, the patient does not feel pain because of the human brain’s unique inability to generate pain signals. Computerized brain-mapping technology is utilized to pinpoint the precise location in the brain where nerve signals generate the tremors and other symptoms. Highly sophisticated imaging and recording equipment are used to map both the physical structure and the functioning of the brain. The electrodes are connected via wires to an internal pulse generator (IPG) that is placed in the chest wall.
A magnet is used with the IPG to adjust the stimulation parameters so that the appropriate level of stimulation is applied at the electrode tip. The patient is provided with an access control device or handheld magnet to turn the IPG on and off at home. Depending on the application, the battery can last three to five years. When the battery needs to be replaced, the IPG is also replaced, usually under local anesthesia as an outpatient procedure.