Elucidating the Temporality of Structural and Functional Connectivity Changes in Essential Tremor After Successful Deep Brain Stimulation to the Dentato-rubro-thalamic Tract

Study Overview
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Brief Summary
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The purpose of this study is to elucidate the structural connectivity of the dentato-rubro-thalamic tract (DRTt) and to detect functional network changes due to DRTt stimulation

Official Title
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Elucidating the Temporality of Structural and Functional Connectivity Changes in Essential Tremor After Successful Deep Brain Stimulation to the Dentato-rubro-thalamic Tract

Conditions
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Essential Tremor

Intervention / Treatment
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* Device: Deep Brain Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the diagnosis of Essential Tremor, made by a movement disorder neurologist, where tremor is not secondary to any disease process or traumatic insult distal appendicular tremor, with minimal proximal component tremor refractory to multiple medication regimens and/or where the medications cause intolerable side effects tremor judged to be severely impacting their quality of life. Exclusion Criteria: significant neurological disorder significant dementia or neurocognitive limitations as assessed by neuropsychiatry (when necessary) severe psychiatric illness with suicidal ideations previous surgery to destroy the target region of the brain surgical contraindications to DBS current major medical problems that affect brain anatomy,neurochemistry, or function, e.g., liver insufficiency, kidney insufficiency, cardiovascular problems, systemic infections, cancer, hypothyroidism, auto-immune diseases, and any current of history of brain disorder (seizure disorder, stroke, dementia, meningitis, encephalitis, degenerative neurologic diseases and head injury with loss of consciousness for any period of time) family history of hereditary neurologic disorder, besides essential tremors ET floating metallic objects in the body pregnancy alcohol or substance abuse/dependence in the past 6 months.

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Deep Brain Stimulation(DBS)<br> | Device: Deep Brain Stimulation<br>* Medtronic Activa device will be implanted and administered clinically, except as part of the trial after 24 months of DBS being on it will be turned off for 3 days and will be turned back on.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Structural connectivity as indicated by fractional anisotropy (FA) as measured by diffusion tensor imaging (DTI) MRI |  | Baseline before DBS implant | 
| Structural connectivity as indicated by fractional anisotropy (FA) as measured by diffusion tensor imaging (DTI) MRI |  | 24 months after start of DBS | 
| Structural connectivity as indicated by mean diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | Baseline before DBS implant | 
| Structural connectivity as indicated by mean diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | 24 months after start of DBS | 
| Structural connectivity as indicated by radial diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | Baseline before DBS implant | 
| Structural connectivity as indicated by radial diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | 24 months after start of DBS | 
| Structural connectivity as indicated by axial diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | Baseline before DBS implant | 
| Structural connectivity as indicated by axial diffusivity as measured by diffusion tensor imaging (DTI) MRI |  | 24 months after start of DBS | 
| Functional connectivity as indicated by blood oxygen level dependent (BOLD) signal as measured by resting state functional MRI (rsfMRI) |  | Baseline before DBS implant | 
| Functional connectivity as indicated by blood oxygen level dependent (BOLD) signal as measured by resting state functional MRI (rsfMRI) |  | 24 months after start of DBS | 
| Functional connectivity as indicated by blood oxygen level dependent (BOLD) signal as measured by resting state functional MRI (rsfMRI) |  | Baseline before DBS is turned off | 
| Functional connectivity as indicated by blood oxygen level dependent (BOLD) signal as measured by resting state functional MRI (rsfMRI) |  | 72 hours after DBS is turned off | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | Baseline before DBS implant | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | 24 months after start of DBS | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | Baseline before DBS is turned off | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | 72 hours after DBS is turned off | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | During DBS placement surgery before active DBS | 
| Tremor as assessed by score on The Essential Tremor Rating Scale (TETRAS) | 10 items are measured-each is scored from 0-4,higher number indicating more tremor | During DBS placement surgery during active DBS | 
| Spectral power recorded during intraoperative electrocorticography (ECoG) |  | During DBS placement surgery before active DBS | 
| Spectral power recorded during intraoperative electrocorticography (ECoG) |  | During DBS placement surgery during active DBS | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ataxia as assessed by score on the Scale for the Assessment and Rating of Ataxia (SARA) | It has eight categories with accumulative score ranging from 0 (no ataxia) to 40 (most severe ataxia). | Baseline before DBS implant | 
| Ataxia as assessed by score on the Scale for the Assessment and Rating of Ataxia (SARA) | It has eight categories with accumulative score ranging from 0 (no ataxia) to 40 (most severe ataxia). | 24 months after start of DBS | 
| Ataxia as assessed by score on the Scale for the Assessment and Rating of Ataxia (SARA) | It has eight categories with accumulative score ranging from 0 (no ataxia) to 40 (most severe ataxia). | Baseline before DBS is turned off | 
| Ataxia as assessed by score on the Scale for the Assessment and Rating of Ataxia (SARA) | It has eight categories with accumulative score ranging from 0 (no ataxia) to 40 (most severe ataxia). | 72 hours after DBS is turned off | 
| Tremor amplitude as assessed by accelerometric power |  | Baseline before DBS is turned off | 
| Tremor amplitude as assessed by accelerometric power |  | 72 hours after DBS is turned off | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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deep brain stimulation