ABSTRACT
Surgical therapies for Parkinson’s disease (PD), notably bilateral stimulation of
the subthalamic nuclei (STN), substantially reduce many of the disabling features
of advanced PD (1-5). Improvements following surgery for PD include ameli-
oration of motor symptoms in the medication “off” condition, reduction in
drug-induced dyskinesias, and decreased requirement for dopaminergic
medications for patients having STN stimulation (6). The benefits of surgery
on motor function appear to be maintained over prolonged periods of
follow-up (7-9).
