Deep Brain Stimulation Effects in Essential Tremor

Study Overview
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Brief Summary
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Deep Brain Stimulation (DBS) is an effective therapy for patients with medically refractory essential tremor. However, DBS programming is not standardized and multiple clinic visits are frequently required to adequately control symptoms. The investigators aim to longitudinally record brain signals from patients using a novel neurostimulator that can record brain signals. The investigators will correlate brain signals to clinical severity scores to identify pathological rhythms in the absence of DBS, and we will study the effects of DBS on these signals in order to guide clinical programming.

Detailed Description
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The development of newer technologies has allowed clinicians and researchers to better understand pathophysiological underpinnings of different disorders managed with neuromodulation. The is now the ability to stream brain signals from a newly FDA approved device, the Medtronic Percept. The investigators will study the longitudinal effects of DBS on the brain signals that are found to correlate with tremor severity as measured with wireless wearable sensors.

Official Title
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Deep Brain Stimulation Effects in Essential Tremor: Time Course of Electrophysiological Changes in Treatment

Conditions
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Essential Tremor

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Patient gives an informed consent. Patient is over 21 years of age. Having a diagnosis of a essential tremor confirmed by a trained movement disorders neurologist; Having failed or not tolerated conventional medical management, at the discretion of the neurologist managing the patient; Exclusion Criteria Having alternative diagnoses to essential tremor; Having comorbid neurodegenerative disorders that may affect mobility or cognition (e.g. comorbid Parkinson's disease or dystonia); Having sequelae of prior brain insult (e.g. prior stroke or brain tumor); History of prior resective brain surgery (e.g. tumor resection); Not being a DBS candidate; Receiving unilateral implants Having a higher surgical risk that precludes patient from having standard intraoperative mapping.

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 85 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with essential tremor<br>Patients with essential tremor who have clinically been deemed candidates for DBS (Deep Brain Stimulation) surgery. Deep brain stimulation is an FDA approved therapy that involves surgical implantation of electrodes in deep brain targets and an implantable pulse generator delivers electrical pulses. This intervention is not part of the study. The investigators are going to recruit patients who receive the Medtronic Percept device, which allows for brain signal recordings (this feature is FDA approved). The investigators will be conducting an observational study using this device to collect data that the subjects receive as standard of care. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fahn- Tolosa- Marin Tremor Rating Scale | A clinical scale of tremor severity (0-4, 0:no symptoms, 4:extreme) | 6 months |