The study, published in the online issue of Biological Psychiatry, reports that the technique is “generally safe” and gives meaningful improvements in patients as early as one month after treatment. Patients also experienced continued, sustained improvement over a period of time.
What is DBS
Deep Brain Stimulation (DBS) employs high-frequency electrical stimulation specially targeted to areas of the brain involved in neuropsychiatric disease.
The system is made up of three parts: an implanted pulse generator (IPG), the lead, and the extension. The IPG is a battery-powered neurostimulator in a titanium housing. It sends electrical pulses to the brain to interfere with neural activity at the target site.
The lead is a coiled wire insulated in polyurethane with four platinum iridium electrodes and is placed in one of three areas of the brain. The lead is connected to the IPG by the extension, an insulated wire that runs from the head, down the side of the neck, behind the ear to the IPG, which is placed subcutaneously below the clavicle or in some cases, the abdomen.
The IPG can be calibrated by a neurologist, nurse or trained technician to optimize symptom suppression and control side effects.
Twenty people received the DBS for 12 months. Twelve of the 20 patients experienced a significant decrease in depressive symptoms (defined by a 50 percent decrease in the Hamilton Depression rating scale) by six months, with seven patients essentially well with few remaining symptoms. Benefits were largely maintained at 12 months with continued stimulation. No long-term side effects were reported.
“In previous studies using brain imaging, we found the subcallosal cingulate region was a key region in an emerging emotion regulation circuit implicated in major depression,"
explains Dr. Helen S. Mayberg, leader of the study team.
“We postulated that if stimulation worked for the treatment of other neurological disorders where abnormal function of specific circuits was well established, such as Parkinson’s disease, then stimulation of the Cg25 region within this apparent depression circuit might provide significant benefit for patients with treatment-resistant depression."
Biological Psychiatry published online July 2008 DOI: 10.1016/jbiopsych.2008.05.034