Treatment of generalized dystonia by deep brain stimulation

Abstract

Objective To evaluate the efficacy of deep brain stimulation in treatment of generalized dystonia. Methods A retrospective analysis was conducted on 20 patients who were implanted with a PINS device at Department of Neurosurgery, Peking Union Medical College Hospital from July 2013 to September 2016. Among them, 13 cases were primary generalized dystonia and 7 cases had secondary generalized dystonia. The scores of Burke-Fahn-Marsden dystonia movement/disability were documented at baseline and at 3, 6, 12 months of follow-up. The rate of improvement was assessed at 12 months postoperatively to evaluate the effectiveness of the PINS DBS system. Comparison was conducted regarding the improvement of scores between groups with different targets and parameters of stimulation. Results Compared with preoperative state, the improvement rates of median BFMDRS-M (Burke-Fahn-Marsden Dystonia Rating Scale-Movement) scores were 86.1% and 43.9% in patients with primary and secondary systemic dystonia at 12 months post surgery, respectively. The improvement rates of median BFMDRS-D (Burke-Fahn-Marsden Dystonia Rating Scale-Disability) scores were 66.7% and 44.4%, respectively, and there was significant difference between pre- and post-operative states (both P 0.05). However, the stimulation parameters of STN-DBS group were significantly lower than those of GPi-DBS group (all P<0.05) in terms of voltage, frequency and amplitude. The follow-up lasted 12-48 months. Only 2 cases developed dyskinesia as the adverse event which resolved or obtained improvement by the end of the study. No adverse effects were classified as severe. Conclusions The deep brain stimulation system domestically manufactured could significantly improve the symptoms of generalized dystonia and demonstrates safety and effectiveness. Key words: Deep drain stimulation; Generalized dystonia; Treatment outcome