Deep brain stimulation (DBS) is a surgical procedure that involves the implantation of a brain pacemaker that delivers electrical impulses to certain parts of the brain.
There are three parts of the deep brain stimulation system. These includes the implanted pulse generator (IPG) or the pacemaker, the leads and the extension. The pacemaker or IPG is a battery operated neurostimulator that lies inside a titanium casing and sends pulses to a target site in the brain to alter the activity there.
The lead consists of a coiled wire insulated with polyurethane, along with four platinum iridium electrodes. This is placed in one of three areas of the brain: the thalamus, the globus pallidus or the subthalamic nucleus. This lead is connected to the IPG by the extension, which is an insulated wire that runs from the side of the head, down behind the ear to the IPG which is implanted below the collar bone or the abdomen. Before activation, the IPG is calibrated and regulated by a neurologist, nurse or technician to allow for maximum efficacy, with minimal side effects.
DBS is a relatively new area of research where therapeutic benefits have been noted in patients with different neurological conditions such as chronic pain, Parkinson's disease, dystonia or tremors. The concept of DBS is not recent but the actual uses, therapeutic benefits, and safety regulations have often been unclear and non-standardized until now.
Previously, permanent lesions used to be created in different parts of the brain for stimulation, but now a removable pacemaker is inserted, meaning the procedure is reversible and also controllable.
In 1997 the Food and Drug Administration (FDA) approved the use of deep brain stimulation for the treatment of essential tremor. It was approved for the treatment of Parkinson's disease in 2002 and for the treatment of dystonia in 2003. Deep brain stimulation has also been studied and used successfully in the treatment of major depression and chronic pain.