Chronic Versus Intermittent Deep Brain Stimulation for Essential Tremor

Study Overview
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Brief Summary
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The proposed study is a randomized, single blind trial of intermittent versus continuous stimulation among essential tremor (ET) patients with a chronic history of continuous stimulation.

Detailed Description
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The proposed study is a randomized, single blind trial of intermittent versus continuous stimulation among essential tremor (ET) patients with a chronic history of continuous stimulation. The trial is 10 weeks in length with clinical evaluations (about 60 minutes) performed on weeks 1, 2, 6, and 10, and phone interviews (about 5 minutes) on weeks 3, 4, 5, 7, 8, and 9. The study includes outcome measures of tremor, stimulation-induced side effects, sleep quality, and voltage threshold for optimal tremor control and sustained side-effects.

Official Title
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Chronic Versus Intermittent Deep Brain Stimulation for Essential Tremor

Conditions
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Essential Tremor

Intervention / Treatment
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* Device: Deep Brain Stimulation (Model 7438 Therapy Controller)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: individuals with essential tremor who are at least 6 months status-post thalamic stimulator placement maintained a consistent chronic or intermittent stimulation schedule for at least 4 consecutive weeks prior to study enrollment no changes in stimulation parameters for at least 2 consecutive months prior to study enrollment Exclusion Criteria: patients with clinically significant dementia (i.e., a score less than 24 out of 30 on the Mini Mental Status Exam14) women who are not post-menopausal patients with other significant neurological or psychiatric disease other than essential tremor patients treated with pallidotomy or thalamotomy patients with significant psychiatric disturbance as determined by Diagnostic and Statistical Manual-IV criteria which would make informed consent/cooperation problematic

Ages Eligible for Study
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Minimum Age: 50 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: Supportive Care
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Deep Brain Stimulation (Model 7438 Therapy Controller)|Deep brain stimulation (DBS) is a surgical procedure used to treat a variety of disabling neurological symptoms|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sleep quality | The trial is 10 weeks in length with clinical evaluations (about 60 minutes) performed on weeks 1, 2, 6, and 10, and phone interviews (about 5 minutes) on weeks 3, 4, 5, 7, 8, and 9. | 10 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| measures of tremor,voltage threshold for optimal tremor control |  | 10 weeks | 
| Side effects |  | 10 weeks |