Successful Management of Hemorrhage-Associated Hemiballism After Subthalamic Nucleus Deep Brain Stimulation with Pallidal Stimulation: a Case Report.

BACKGROUND Deep brain stimulation has been widely used for treating several movement disorders including idiopathic Parkinson disease (IPD). The development of hemiballism after an iatrogenic injury to the subthalamic nucleus (STN) such as postoperative hemorrhage or stroke is rare. Employing pallidal DBS to manage hemiballism arising as a result of STN injury is a unique application of this therapeutic modality, which has only been reported twice in the literature. CLINICAL PRESENTATION We present a case of a 54-year-old male with levodopa-responsive IPD who underwent STN electrode placement for deep brain stimulation. The immediate postoperative course was uneventful, but the patient suffered a fall 12 weeks after electrode implantation, leading to electrode displacement and subsequent STN hemorrhage, which led to hemiballism. The hemiballism was then subsequently treated with pallidal DBS after medical management was unsuccessful. CONCLUSION In our case pallidal DBS was effective in treating hemiballism that arose as a result of traumatic displacement of STN DBS electrodes. Medical management and changes in stimulation parameters failed to produce any significant change in the hemiballism. This report is only the third of its kind in the literature wherein hemiballism arising as a result of STN damage after DBS was successfully treated with pallidal stimulation.