Long-term benefit sustained after bilateral pallidal deep brain stimulation in patients with refractory tardive dystonia

Background/Aims: Tardive dystonia (TD) can be a highly disabling, permanent condition related to the use of dopamine-receptor-blocking medications. Our aim was to evaluate the long-term effect of bilateral pallidal deep brain stimulation (DBS) for TD. Methods: Five consecutive patients with disabling TD who underwent stereotactic placement of bilateral globus pallidus internus DBS leads were included. All patients had a history of mood disorder or schizophrenia previously treated with neuroleptic medication, with a mean duration of motor symptoms of 10.2 years. Dystonia severity was measured using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) movement score by a blinded neurologist reviewing pre- and postoperative videotaped examinations. Results: The mean baseline movement BFMDRS score was 49.7 (range 20-88). Overall, we observed a mean reduction of 62% in the BFMDRS movement score within the first year after surgery. Persistent improvement in dystonia (71%) was seen at the last follow-up ranging from 2 to 8 years after surgery. Conclusion: Our experience suggests that pallidal DBS can be an effective therapy with long-term benefits for patients with TD.