Bilateral globus pallidus internus deep brain stimulation in Parkinson's disease with periodic limb movement disorder.

Deep brain stimulation for Parkinson's disease is a well-established therapeutic intervention for refractory disease. The main nuclear targets are the subthalamic nucleus and the globus pallidus internus. Periodic limb movements are often an associated condition in patients with Parkinson's disease. Both conditions can respond to dopaminergic agents. The case of a 57-year-old man with severe Parkinson's disease and periodic limb movement who underwent bilateral globus pallidus deep brain stimulation surgery for his Parkinson's disease is presented and discussed. Intraoperatively the patient's periodic limb movements responded to voltage stimulation higher than those required for improvement of his parkinsonian symptoms. The immediate and reversible improvement in these symptoms contralateral to the stimulation site suggests pallidal stimulation may directly ameliorate periodic limb movement symptoms.