Deep Brain Stimulation of the Subthalamic Nucleus for the Treatment of Parkinson's Disease

Levodopa remains the gold standard for the treatment of Parkinson's disease (PD). However, its chronic use is associated with motor and psychiatric com plications causing significant disability. Thus, there is a need for alternative approaches including surgical treatment. Better understanding of basal ganglia circuitry and the availability of an experimental animal model of Parkinson's disease in the form of the 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP)-treated monkey have made evident the crucial role of the subthalamic nucleus (STN) in basal ganglia function. Deep brain stimulation (DBS) has become an acceptable treatment option, improving quality of life (QOL) for PD patients with medically intractable symptoms. Good pre-operative levodopa respon siveness and younger age appear to be the best predictors of surgical success, particularly with respect to improvement in motor function. Although benefits in mobility are achieved, complications are not infrequent, and risk—benefit ratio should be assessed on an individual basis for each patient depending on personal preferences, s ocioeconomic status, and local disease demographics. In this chapter, a comprehensive review of the current literature on the topic is pre sented in addition to our own results with STN DBS for the treatment of PD.