One Pass thalamIc aNd subthalamIc stimulatiON

Tremor is the most salient symptom of Parkinson's disease (IPS=idiopathic Parkinson syndrome). Other symptoms are bradykinesia, rigidity and postural instability. As much as 75% of patients with IPS show resting tremor. Initially, tremor is typically unilateral and only visible in stress situation. In the later stage of the disease it becomes bilateral. The OPINION trial aims at the investigation of a combined approach to thalamic/subthalamic deep brain stimulation (DBS) for the treatment of patients with tremor dominant IPS or patients with equivalent type IPS who perceive tremor to be their dominant symptom. The planned approach will for the first time allow for the direct comparison of each condition in a homogeneous patient population and will furthermore allow an intra-individual comparison of the different stimulation conditions (Ventral intermediate nucleus (Vim/DRT) - Subthalamic nucleus (STN) - Vim/DRT+STN) with the outcome parameter "quality of life". Patients will be registered to the trial and will undergo screening procedures (for eligibility criteria please see Inclusion and Exclusion criteria). If the patient is eligible the Investigational Medical Device (IMD) will be implanted (which is the Vercise™ Deep Brain Stimulation System manufactured by Boston Scientific). After implantation the IMD will remain OFF for a period of 1 month. 1 month after implantation treatment will be started. Patients will be randomized to one of the following 3 treatment groups: Subthalamic nucleus (STN) or Ventral intermediate nucleus (Vim/DRT) or combined stimulation (Vim/DRT+STN). Patients will undergo all three treatment groups each lasting 3 months. The patient is blinded meaning that study patients will not know what kind of treatment (e.g. mode/region of stimulation) they receive. 10 months after implantation the final visit of the randomized study will be performed. After that, patients will be asked to take part in an open label extension phase of the study where they will be treated unblinded according to established guidelines and according to their own preferred stimulation mode, just as they would be in a clinical routine setting. The extension phase is concluded by an end of study visit at 36 months after implantation. After the end of the trial, further treatment will be performed at the Department of Stereotactic and Functional Neurosurgery in Freiburg (Germany) according to established guidelines. Devices will be monitored 3-6 monthly Patient's medications will be adjusted as to the level of best treatment adjunct to stimulation. Study endpoints (e.g. quality of life) will be evaluated by a blinded rater. In addition, an external video rating will be performed.