Subthalamic stimulation in Parkinson disease - A multidisciplinary approach

Background: High-frequency stimulation of the subthalamic nucleus constitut es a therapeutic advance for severely disabled patients with Parkinson dise ase. Objective: To evaluate the efficacy and safety of continuous bilateral high -frequency stimulation of the subthalamic nucleus in patients with Parkinso n disease. Design: A prospective study of patients with Parkinson disease treated at a university hospital. Patients and Methods: Electrodes were implanted bilaterally in the subthala mic nucleus of 21 consecutive patients with Parkinson disease who responded well to levodopa but had severe motor complications. There were 16 men and 7 women (mean +/- SEM age, 53 +/- 2 years) who had a mean +/- SEM disease duration of 14.7 +/- 1.0 years. Targets were determined by 3-dimensional ma gnetic resonance imaging, combined with intraoperative electrophysiologic r ecordings and stimulation. Results: Six months after surgery, motor disability, levodopa-induced motor fluctuations, dyskinesias, and the daily dose of levodopa equivalent decre ased significantly by 67%, 78%, 77%, and 61%, respectively, compared with t he preoperative state. No significant morbidity was observed, except transi ent depression in 4 patients. Conclusions: The beneficial effects of subthalamic stimulation depend on (1 ) the criteria used for patient selection, (2) the precision with which the subthalamic nucleus is targeted (dependent on the 3-dimensional magnetic r esonance imaging and the intraoperative electrophysiologic and clinical ass essments), and (3) the long-term postoperative adjustment of stimulation va riables.