High-frequency deep brain stimulation for the treatment of movement disorders

Stereotactic surgery for movement disorders has regained importance in rece nt years. Reasons for this development are a better understanding of the pa thophysiology of movement disorders, safer surgical procedures and a clear definition of indications for surgery. Thalamotomy for the treatment of all types of drug resistant tremors and pallidotomy for treating akinesia, rig idity and L-Dopa induced dyskinesias in Parkinson's disease are established therapies. During these routine procedures a stereotactic lesion is placed in the target area. Deep brain stimulation via chronically implanted elect rodes is a new interesting therapeutical alternative to the established des tructive procedures. The high-frequency stimulation with low currents leads to a functional blockade of stimulated areas. For this purpose a commercia lly available stimulating electrode is stereotactically implanted into the target area and connected to a current generator placed into an infraclavic ular skin pocket. The indication for deep brain stimulation of the thalamus corresponds to the indication for thalamotomy. The advantages of deep brai n stimulation lie in the possibility of performing safe bilateral procedure s, the lower risk of permanent neurological deficits, the individual adapta bility of stimulation parameters throughout the course of the disease and t he principal reversability. Chronic bilateral high frequency stimulation of the pallidum and subthalamic nucleus are promising therapies for the sympt omatic relieve of all cardinal symptoms in advanced Parkinson's disease. Th e long-term results are being investigated currently.