Sunday, June 05, 2011

Recent advances in psychosurgery

Dr. Robert Hirschfeld wrote an Editorial in the Am. J. of Psychiatry concerning a paper published in the same Journal. We transcribe the following paragraphs from the Editorial. “In recent years several experimental neurosurgical procedures have been tried for severe intractable psychiatric disorders. Several of these procedures include targeted ablations such as anterior capsulotomy, anterior cingulotomy, and subcaudate tractotomy. An alternative to ablation procedures is intracranial electrical stimulation of targeted areas of the brain, or deep brain stimulation (DBS). This involves stereotactical implantation of intracranial electrodes that are connected to an implanted impulse generator in the chest wall. Advantages of DBS over lesioning include potential reversibility, revisability, and adjustability.
Research on the efficacy and safety of DBS for treatment-resistant depression has been limited to small open-label studies and case reports. The largest study to date involves 20 patients at several academic centers who received 6 months of DBS to the subcallosal cingulate gyrus (Brodmann’s area 25). To qualify for the study, patients had to be in an episode of major depression for at least 1 year and had to have failed to respond to at least four different treatments (including antidepres- sant, psychotherapy, and ECT). The initial 6-month response in these patients was 60%, and the remission rate was 30%. An article in this issue by Kennedy and colleagues (Kennedy SH, Giacobbe P, Rizvi SJ, Placenza FM, Nishikawa Y, Mayberg HS, Lozano AM: Deep brain stimulation for treatment-resistant depression: follow-up after 3 to 6 years. Am J Psychiatry 2011; 168:502–510[Abstract/Free Full Text]) describes an extended follow-up (mean duration, 3.5 years) of these patients. The long-term outcome of these severely ill patients is encouraging. The average response rate at the last follow-up visit was 64%, and the remission rate was 35%. Psychosocial functioning and physical health had improved substantially over time, and there were no significant DBS-related adverse events."