Evaluation of Directional Stimulation During the Implantation of Deep Brain Stimulation (DBS) Leads

Study Overview
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Brief Summary
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The purpose of this study is to provide proof-of-concept that directional stimulation, in an intraoperative setting, is perceivable in a subject and is different from omnidirectional stimulation. The tests will be performed using a dedicated DBS lead connected to external neurostimulator.

Official Title
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Evaluation of Directional Stimulation During the Implantation of Deep Brain Stimulation Leads for the Treatment of Movement Disorders

Conditions
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Parkinson's Disease, Essential Tremor

Intervention / Treatment
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* Device: directSTN Acute lead connected to external neurostimulator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is indicated to undergo DBS for Parkinson's disease or Essential Tremor according to criteria of the Study site For Parkinson Disease: Person is between 18 and 75 years of age Established diagnosis of idiopathic Parkinson's disease with progression of symptoms for a minimum of 2 years. Person has a history of at least 30% improvement on the Unified Parkinson's Disease Rating Scale with therapy in L-dopa (levodopa) Weak control of symptoms by dopaminergic therapy (off phenomenon, fluctuations on / off, dyskinesia on) For Essential Tremor: Person is between 18 and 80 years of age Established diagnosis of Essential Tremor for a minimum of 2 years Functional disability due to tremor was not adequately controlled by medication for at least 3 months prior to implant. Person has given his/her written consent Exclusion Criteria: Person suffering from an active major psychiatric disorder Mattis Dementia Rating Scale score <130 or otherwise not capable of discernment Presence of major co-morbidity or medical condition that may affect participation to the study Presence of an electrical or electromagnetic implant (e.g., cochlear implant, pacemaker) Person with a previous surgery for the treatment of Parkinson's disease or Essential Tremor Person with a previous brain ablation procedure Person who suffers from epilepsy Person who is pregnant: a pregnancy test will be performed in women of childbearing age Person with coagulopathies Abuse of drugs or alcohol

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Directional lead<br> | Device: directSTN Acute lead connected to external neurostimulator<br>* Test phase will be performed intra-operatively, prior to chronic lead implant<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measurement of the therapeutic window's boundaries when stimulating in specific angular directions, and comparison to those obtained when stimulating in all directions. | A therapeutic window is defined as the difference between the electrical current threshold at which a desired therapeutic effect is obtained and the current threshold at which side effects appear. | up to one hour during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Electrical functionality of the study device during the test phase | The electrical integrity of the device will be measured before and after its use, to confirm that it was functional throughout the test phase. | 1 day |