• Montgomery-Asberg Depression Rating Scale (MADRS), Hamilton Depression Rating Scale (HDRS) [ Time Frame: These scales are administered on each postoperative clinic visit. Visits occur monthly, except during the open continuation phase, when they occur every three months. ]
  

• Inventory for Depressive Symptoms, Self-report (IDS-SR), Clinical Global Impressions (CGI), Patient Global Impressions (PGI), Global Assessment of Functioning (GAF), Social and Occupational Function Assessment Scale (SOFAS), Quality of LIfe Enjoyment and [ Time Frame: These measures will be obtained at baseline, at the end of the initial chronic phase (typically after three months of chronic stimultion), at the end of the open continuation phase (at two years into the study). ]
  

This protocol proposes a clinical study of therapeutic benefits of ventral capsule/ventral striatum deep brain stimulation (DBS) as a treatment in ten patients with intractable major depression (MD). Conservative estimates place MD's prevalence at 2.6% to 5.5% in men and 6.0% to 11.8% in women. Most conservative studies estimate a 20% complete refractoriness to medical and psychotherapeutic regimens. Given the prevalence of major depression in the general population, over 3.5 million Americans would be expected to manifest refractory illness if all those with depression received treatment. Study subjects will have MD of disabling severity, intractable to prolonged treatment attempts with conventional medication and pschotherapies. They must also have had electroconvulsive therapy. These refractory patients would be candidates for a destructive/lesioning brain surgery such as a radiofrequency cingulotomy.

These MD patients are analogous to medically intractable Parkinson's disease and tremor patients who until recently underwent similar destructive surgeries such as a pallidotomy or thalamotomy. The use of DBS technology with its inherent advantage of being fully reversible and adjustable has become standard of care for these disabled patients. Studies have demonstrated improved safety and efficacy of DBS over lesioning.

Recently, DBS technology has been employed in the lesioning target of the anterior limb of the internal capsule for OCD. These preliminary studies in Europe and now the US, are demonstrating improved outcomes for refractory OCD patients with regard to their OC symptoms as well as depressed mood. This amelioration of mood provides the basis on which anterior internal capsule DBS may help major depression patients.

Based on this rationale, we believe that DBS is a viable therapeutic surgical option in this group of severely ill MD patients. The standard DBS stereotactic surgical techniques employed by the CCF team in hundreds of movement disorder patients will be used. The DBS electrodes will be implanted bilaterally in the anterior limb of the internal capsule and connected subcutaneously to subclavicular programmable pulse generators.