Deep brain stimulation of the subthalamic nucleus and globus pallidus internus for advanced Parkinson’s disease

Deep Brain Stimulation (DBS) for Parkinson’s disease is a treatment option in patients with medication-induced motor response fluctuations, when medication schedule adjustments are no longer able to sustain optimal functioning in daily life. DBS mainly improves motor symptoms that initially responded well to dopaminergic treatment, such as tremor, bradykinesia and rigidity. DBS also reduces the time spent in off-drug phase, dyskinesias, and medication use. The most important complications of surgery are intracerebral hematoma (rarely encountered), infection, hardware complications, and cognitive impairment and behavioral changes. Both globus pallidus parts interna (GPi) DBS and subthalamic nucleus (STN) DBS improve motor symptoms, but it is unclear which nucleus improves symptoms more. Moreover, STN DBS might be associated with more side-effects on cognition, mood, and behavior. The Netherlands SubThalamic And Pallidal Study (NSTAPS) is a randomized controlled trial that compares outcome after GPi DBS and STN DBS up to three years after surgery. Functioning, cognition, mood, behavior, motor symptoms, quality of life and complications of surgery are evaluated. The results are discussed in this thesis. The hypothesis of the study was that GPi DBS and STN DBS give a similar improvement in motor symptoms, but that GPi DBS would result in a better daily functioning due to fewer adverse effects on cognition, mood, and behavior