Deep Brain Stimulation (DBS) of the Nucleus Basalis of Meynert (NbM) in Patients With Parkinson's Disease

Study Overview
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Brief Summary
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The existing DBS setting in patients with DBS of the globus pallidus interna (GPi), which aims to treat motor symptoms by a high-frequency stimulation, will be temporarily reprogramed to stimulate the NbM at a low frequency using the distal electrodes positioned in the vicinity of the NBM. This study aims to investigate the neuropsychological effect of low frequency stimulation of the nucleus basalis of Meynert (NBM) in advanced Parkinson's disease (PD) patients, who were previously treated with deep brain stimulation (DBS) of the globus pallidus interna (GPi).

Detailed Description
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The existing DBS setting in patients with GPi DBS, which aims to treat motor symptoms by a high-frequency stimulation, will be temporarily reprogramed to stimulate the NBM at a low frequency using the distal electrodes positioned in the vicinity of the NBM.This study consists of a three-day screening study of the NbM stimulation followed by a two-week, randomized, single-blind, crossover trial. Between the screening study and the crossover trial, one week of washout period will be applied to eliminate potential carryover effect from the previous stimulation. This study aims to investigate the neuropsychological effect of low frequency stimulation of the nucleus basalis of Meynert (NBM) in advanced Parkinson's disease (PD) patients, who were previously treated with deep brain stimulation (DBS) of the globus pallidus interna (GPi).

Official Title
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Deep Brain Stimulation (DBS) of the Nucleus Basalis of Meynert (NbM) in Patients With Parkinson's Disease: A Pilot Study

Conditions
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Cognitive Deficit

Intervention / Treatment
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* Device: NBM-DBS
* Device: DBS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with GPi stimulation, with the NBM within the vicinity of the electric field of at least one DBS electrode. Patients should be able to give informed consent Patients should be on a stable medication regimen for at least 4 weeks Exclusion Criteria: any unstable internal disease Subject with significant worsening of motor function during the pilot screening study, which is indicated by an increase of the UPDRS part III score more than 30%, will not continue to the crossover trial
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: NBM-DBS on<br>DBS is programmed to stimulate the NbM | Device: NBM-DBS<br>* DBS which has already been implanted aiming initially to stimulate the GPi will be reprogrammed in order to stimulate more distal structure, the NBM.<br>|
| Placebo Comparator: DBS off<br>DBS is turned off, no stimulation will be exerted | Device: DBS<br>* DBS will be switched off<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in global cognitive function measured by the Scales for Outcomes in Parkinson's disease-Cognition (SCOPA-COG) |  | 2 weeks of the crossover trial phase | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of Unified Parkinson's Disease Rating Scale (UPDRS) part 3 |  | 3 days of the screening phase | 
| Changes of the power of background EEG frequencies |  | 2 weeks of the crossover trial phase | 
| Score changes of stroop test |  | 2 weeks of the crossover trial phase | 
| Score changes of the Trail Making test |  | 2 weeks of the crossover trial phase | 
| Score changes of the digit span test of Wechsler Adult Intelligence Scale III |  | 2 weeks of the crossover trial phase | 
| Score changes of the symbol digit modality test (SDMT) |  | 2 weeks of the crossover trial phase | 
| Score changes of the Hospital Anxiety and Depression Scale |  | 2 weeks of the crossover trial phase | 
| Score changes of the Apathy Evaluation Scale |  | 2 weeks of the crossover trial phase |