Correlation of Tractography and Motor Evoked Potentials in Deep Brain Stimulation

Study Overview
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Brief Summary
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The goal is to establish another anatomical referencing system in order to achieve an even higher accuracy when implanting stimulation electrodes.

Detailed Description
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The main goal is to find out what are the optimal distances to these reference fiber tracts when stimulating and to find the optimal target. This has to be evaluated for each target, such as globus pallidus (Gpi), subthalamic nucleus (STN) and ventral intermediate nucleus of the thalamus (VIM) separately. This is of special importance as the investigators can demonstrate the internal capsule, which is often a generator of stimulation-induced side effects: tetanic muscle contractions, dysarthria and gaze deviations.

Official Title
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Correlation of Tractography and Motor Evoked Potentials in Deep Brain Stimulation

Conditions
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Improving Accuracy of Implanting Stimulation Electrodes

Intervention / Treatment
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* Procedure: Deep Brain Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient qualifying for deep brain stimulation on the basis of a movement disorder (Parkinson's Disease, tremor, dystonia) or chronic pain disease. Informed consent Exclusion Criteria: Lack of consent Electrical or other devices that preclude the performance of an MRI
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Subthalamic Nucleus (STN)<br>Patients with Parkinson's disease | Procedure: Deep Brain Stimulation<br>* Deep Brain Stimulation<br>|
| Globus Pallidus (Gpi)<br>Patients with Dystonia | Procedure: Deep Brain Stimulation<br>* Deep Brain Stimulation<br>|
| Ventral intermediate nucleus of the thalamus (VIM)<br>Patients with Tremor | Procedure: Deep Brain Stimulation<br>* Deep Brain Stimulation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| distance between stimulation electrode and motor fibers in mm | Distances between the stimulation electrode and motor fibers as depicted on fiber tracking in millimeters in correlation to the threshold current for eliciting clinical side effects | Intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraoperative intensity of stimulation in milliampere (mA) | Intraoperative intensity of stimulation in milliamp, which elicits an activation of contralateral muscle groups (musculus interosseus dorsalis and the musculus tibialis anterior) | Intraoperative | 
| Stimulation thresholds in milliampere (mA) | Threshold of intraoperative stimulation intensity in milliamp, which elicits capsular side effects | Intraoperative | 
| Change in disease score units on the UPDRS rating scale | Assessment of therapeutic effects using Unified Parkinson disease rating scale (UPDRS) | twelve months | 
| Change in disease score units on the FTRS rating scale | Assessment of therapeutic effects using, Fahn-Tremor Rating Scale (FTRS) | twelve months | 
| Change in disease score units on the BFMDRS rating scale | Assessment of therapeutic effects using Burke-Fahn-Marsden dystonia rating scale (BFMDRS) | twelve months | 
| Change in disease score units on the TWSTR rating scale | Assessment of therapeutic effects using Toronto Western Spasmodic torticollis rating scale (TWSTR) | twelve months | 
| Change in disease score units on the PDQ-39 rating scale | Assessment of therapeutic effects using Parkinsons Disease QuestionnairePDQ-39 | twelve months |