Failure of long-term pallidal stimulation corrected by subthalamic stimulation in PD

Bilateral high-frequency continuous stimulation of the internal globus pall idus or subthalamic nucleus constitutes a new therapeutic approach for the treatment of patients with severe PD. The authors report two patients in wh om stimulation of the globus pallidus failed to give longterm relief and wa s successfully replaced by bilateral subthalamic stimulation. The results e mphasize the reversibility of deep brain stimulation therapy and suggest th at the subthalamic target is preferable to the pallidal target.