Deep brain stimulation for the treatment of obsessive-compulsive disorder

A group of researchers at Charité-Universitätsmedizin Berlin has further refined deep brain stimulation in the treatment of obsessive-compulsive disorder. By pinpointing the placement of electrodes in patients' brains, researchers were able to identify a fiber tract. They associate this with the best clinical results after deep brain stimulation. In addition, medicine can use the results of researchers to improve medical treatment of suchpsychological problemsbenefit.

New perspectives for deep brain stimulation

A person with OCD experiences unwanted thoughts and behaviors that are difficult or impossible to resist. Obsessive thoughts and compulsive behaviors affect more than 2 percent of people. This condition can therefore severely affect daily activities. However, one treatment option for severe cases is deep brain stimulation. This is a technique that medical professionals also use with othersDiseases such as Parkinson'sor apply depression.

Deep brain stimulation, as the name suggests, involves implanting tiny electrodes into structures deep in the brain. Once implanted, these electrodes deliver very weak electrical currents to restore balance to brain activity. This occurs by stimulating different areas of the brain, such as a fiber tract within the inner nucleus or the subthalamic nucleus. So this technique can help improve clinical symptoms in some cases. However, the success of the treatment depends on the exact placement of the electrodes. Furthermore, this requires precision at a microscopic level. However, the optimal stimulation target for patients with OCD has not yet been identified.

Research results

For the first time, a research team led by Dr. Andreas Horn from the Charité Department of Neurology used experimental neurology to identify a specific nerve bundle. This appears to be an optimal target for deep brain stimulation. Researchers studied 50 patients with obsessive-compulsive disorder who they treated at a number of centers around the world. They used magnetic resonance imaging technology both before and after electrode placement. The researchers were able to visualize the surrounding fiber tracts and test which of these electrodes stimulated selectively. The analysis showed that optimal results are associated with a very specific nerve bundle. Reliable evidence of this connection was found in all cohorts of patients examined in Cologne, Grenoble, London and Madrid, explains Dr. Horn.

So the researchers first examined two cohorts of patients, both of whom received deep brain stimulation of the inner nucleus or subthalamic nucleus. These brain structures have a variety of connections to other areas of the brain. Nevertheless, a specific tract between the prefrontal cortex and the subthalamic nucleus was identified as a suitable target for stimulation in both groups. Through precise localization, the researchers were able to reliably predict treatment outcomes in both groups. The neurologists then repeated these results in two additional independent cohorts. When comparing the results with other studies, the researchers showed that the target areas described were also within the tract target identified in this study.

All 3D structural analysis data has been made publicly available to researchers around the world. However, neurologists are not yet treating Charité patients with obsessive-compulsive disorder with this invasive method of deep brain stimulation. However, participating research centers continue to share their knowledge and develop protocols for additionalStudies like thisto test the newly defined target areas.