Deep brain stimulation for bipolar disorder-review and outlook.

Research on deep brain stimulation (DBS) for treatment-resistant psychiatric disorders has established preliminary efficacy signals for treatment-resistant depression. There are only few studies on DBS that included patients suffering from bipolar disorder. This article gives an overview of these studies concerning DBS targets, antidepressant efficacy, and the occurrence of manic/hypomanic symptoms under stimulation. First, promising results show that all patients experienced significant improvement in depressive symptomatology. In a single case, hypomanic symptoms occurred, but they could be resolved by adjusting stimulation parameters. Furthermore, this article highlights important clinical differences between unipolar and bipolar depression that have to be considered throughout the course of treatment.

Degree of Postictal Suppression Depends on Seizure Induction Time in Magnetic Seizure Therapy and Electroconvulsive Therapy.

OBJECTIVES: Anesthesia is required for both magnetic seizure therapy (MST) and electroconvulsive therapy (ECT), although it has anticonvulsant properties. In this case, bispectral index (BIS) monitoring, a specific electroencephalogram-derived monitoring, can be used to find the optimal seizure induction time during anesthesia to elicit adequate seizures. A measurement of seizure adequacy in electroencephalogram is the postictal suppression. The purpose of this study was to investigate the influence of seizure induction time on the degree of postictal suppression by comparing BIS versus no-BIS monitoring in MST and ECT. METHODS: Twenty patients with treatment-resistant depression were randomly assigned to either MST or ECT. Each patient underwent 3 treatments with the determination of seizure induction time by defined prestimulation BIS (BIS condition) and 3 treatments with determination of seizure induction time by controlled clinical trial protocol (no-BIS condition). Statistical analysis was calculated by repeated-measures analysis of variance. RESULTS: The degree of postictal suppression was more pronounced in both MST and ECT, with BIS monitoring. In this connection, no differences between MST and ECT were found. Seizure induction time was significantly later in the BIS condition (181.3 ± 6 seconds) compared with the no-BIS condition (114.3 ± 12 seconds) (P < 0.001). CONCLUSIONS: Adequacy of seizures, in the form of the degree of postictal suppression, was superior by determining the seizure induction time with BIS in both MST and ECT. Further research is needed to investigate the correlation between the degree of postictal suppression and treatment response.

Arachnophobia alleviated by subthalamic nucleus stimulation for Parkinson's disease.

We report on a Parkinson patient with motor fluctuations and dyskinesias in whom deep brain stimulation (DBS) of the subthalamic nucleus (STN) not only improved motor symptoms but also pre-existing arachnophobia. Arachnophobia had been unchanged by the course of Parkinson's disease but rapidly improved with STN-DBS. Both, motor effects and the improvement of arachnophobia were stable during 2 years follow-up. To our knowledge this is the first report on STN stimulation effects on a specific phobia.

Deep brain stimulation to the medial forebrain bundle for depression- long-term outcomes and a novel data analysis strategy.

BACKGROUND: Deep brain stimulation (DBS) of the supero-lateral branch of the medial forebrain bundle (slMFB) in treatment-resistant depression (TRD) is associated with acute antidepressant effects. OBJECTIVE: Long-term clinical effects including changes in quality of life, side effects and cognition as well as long-term data covering four years are assessed. METHODS: Eight TRD patients were treated with DBS bilateral to the slMFB. Primary outcome measure was a 50% reduction in Montgomery-Åsberg Depression Rating Scale (MADRS) (response) and remission (MADRS <10) at 12 months compared to baseline. Secondary measures were anxiety, general functioning, quality of life, safety and cognition assessed for 4 years. Data is reported as conventional endpoint-analysis and as area under the curve (AUC) timeline analysis. RESULTS: Six of eight patients (75%) were responders at 12 months, four patients reached remission. Long-term results revealed a stable effect up to four years. Antidepressant efficacy was also reflected in the global assessment of functioning. Main side effect was strabismus at higher stimulation currents. No change in cognition was identified. AUC analysis revealed a significant reduction in depression for 7/8 patients in most months. CONCLUSIONS: Long-term results of slMFB-DBS suggest acute and sustained antidepressant effect; timeline analysis may be an alternative method reflecting patient's overall gain throughout the study. Being able to induce a rapid and robust antidepressant effect even in a small, sample of TRD patients without significant psychiatric comorbidity, render the slMFB an attractive target for future studies.