Mood improvement after deep brain stimulation of the internal globus pallidus for tardive dyskinesia in a patient suffering from major depression

Deep brain stimulation (DBS) has the unique characteristic to very precisely target brain structures being part of functional brain circuits in order to reversibly modulate their function. It is an established adjunctive treatment of advanced Parkinson's disease and has virtually replaced ablative techniques in this indication. Several cases have been published relating effectiveness in neuroleptics-induced tardive dyskinesia. It is also investigated as a potential treatment of mood disorders. We report on the case of a 62 years old female suffering from a treatment refractory major depressive episode with comorbid neuroleptic-induced tardive dyskinesia. She was implanted a deep brain stimulation treatment system bilaterally in the globus pallidus internus and stimulated for 18 months. As well the dyskinesia as also the symptoms of depression improved substantially as measured by the Hamilton Rating Scale of Depression (HRSD) score and the Burke-Fahn-Marsden-Dystonia-Rating-Scale (BFMDRS) score. Scores dropped for HRSD from 26 at baseline preoperatively to 13 after 18 months; and for BFMDRS from 27 to 17.5. This case illustrates the potential of deep brain stimulation as a technique to be investigated in the treatment of severe and disabling psychiatric and movement disorders. DBS at different intracerebral targets being actually investigated for major depression might have similar antidepressant properties because they interact with the same cortico-basal ganglia-thalamocortical network found to be dysfunctional in major depression.