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.