Short-term and long-term safety of deep brain stimulation in the treatment of movement disorders

OBJECT: The object of this study was to assess the long-term safety of deep brain stimulation (DBS) in a large population of patients with a variety of movement disorders. METHODS: All patients treated with DBS at the authors' center between 1995 and 2005 were assessed for intraoperative, perioperative, and long-term adverse events (AEs). A total of 319 patients underwent DBS device implantation. Of these 319, 182 suffered from medically refractory Parkinson disease; the other patients had essential tremor (112 patients), dystonia (19 patients), and other hyperkinetic movement disorders (six patients). Intraoperative AEs were rare and included vasovagal response in eight patients (2.5%), syncope in four (1.2%), severe cough in three (0.9%), transient ischemic attack in one (0.3%), arrhythmia in one (0.3%), and confusion in one (0.3%). Perioperative AEs included headache in 48 patients (15.0%), confusion in 16 (5.0%), and hallucinations in nine (2.8%). Serious intraoperative/perioperative AEs included isolated seizure in four patients (1.2%), intracerebral hemorrhage in two patients (0.6%), intraventricular hemorrhage in two patients (0.6%), and a large subdural hematoma in one patient (0.3%). Persistent long-term complications of DBS surgery included dysarthria (4.0%), worsening gait (3.8%), cognitive dysfunction (4.0%), and infection (4.4%). Revisions were completed in 25 patients (7.8%) for the following reasons: loss of effect, lack of efficacy, infection, lead fracture, and lead migration. Hardware-related complications included 12 lead fractures and 10 lead migrations. CONCLUSIONS: The authors conclude that in their 10-year experience, DBS has proven to be safe for the treatment of medically refractory movement disorders.