Transcranial Electrical Stimulation for Cervical Dystonia

Study Overview
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Brief Summary
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There are two phases. Phase I: A single visit which includes a screening, clinical scales, and a MRI scan with simultaneous tES/sham tES in a randomized block design. Enrolls both Cervical Dystonia (CD) patients and healthy controls. Phase II: 5 consecutive days of 30-90 min visits to campus for tES or sham tES. Transcranial magnetic stimulation (TMS) measures and clinical scales will also be included on Day 1 and Day 5 visits. Enrolls only CD patients.

Detailed Description
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Phase I: Enrolls both CD patients and healthy controls. One approximately 3 hour visit which includes: a screening & neurological exam, clinical scales & questionnaires, a (approx.) 60 min MRI scan with simultaneous tES/sham tES in a randomized block design and EMG Phase II: Enrolls only CD patients. Five consecutive days of study visits. Day 1: TMS screening, repeated neurological assessment and clinical scales if >1 month since MRI visit 30 min TMS session with concurrent EMG 20 min tES or sham tES session Days 2-4: - 20 min tES or sham tES session Day 5: 20 min tES or sham tES session 30 min TMS session with concurrent EMG repeated neurological assessment and clinical scales

Official Title
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Transcranial Electrical Stimulation (tES) for the Treatment of Cervical Dystonia

Conditions
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Primary Cervical Dystonia

Intervention / Treatment
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* Device: transcranial electrical stimulation


Participation Criteria
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Eligibility Criteria
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Primary Cervical Dystonia Inclusion Criteria: Right-handed On a stable dose of all medications used to treat dystonia for the month previous to enrollment No botox injections in the 10 weeks previous to enrollment Exclusion Criteria: Any contraindication to MRI scanning, tES, or TMS (e.g pregnancy, history of seizures, significant systemic medical conditions, untreated psychiatric or neurological conditions) Evidence on neurological exam of any potentially confounding neurological disorder Evidence of significant cognitive impairment Patients with dystonia symptoms beginning prior to the age of 18 will be excluded Patients with secondary dystonia resulting from medications or that are part of another neurological disorder (e.g. Parkinson's disease) will be excluded Medication that might predispose the subject to seizures Healthy Controls Inclusion Criteria: - Right-handed Exclusion Criteria: Any contraindication to MRI scanning, tES, or TMS (e.g pregnancy, history of seizures, significant systemic medical conditions, untreated psychiatric or neurological conditions) Evidence on neurological exam of any potentially confounding neurological disorder Evidence of significant cognitive impairment Medication that might predispose the subject to seizures

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: MRI - HC tDCS<br>Healthy controls in Phase 1 transcranial electrical stimulation set to direct current | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|
| Active Comparator: MRI - HC tACS<br>Healthy controls in Phase 1- transcranial electrical stimulation set to alternating current | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|
| Active Comparator: MRI - CD tCDS<br>Cervical dystonia in Phase 1 transcranial electrical stimulation set to direct current | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|
| Active Comparator: MRI - CD tACS<br>Cervical dystonia in Phase 1 transcranial electrical stimulation set to alternating current | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|
| Active Comparator: Phase II - Stim<br>Cervical dystonia in Phase 2 transcranial electrical stimulation setting is active | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|
| Sham Comparator: Phase II - Sham<br>Cervical dystonia in Phase 2 transcranial electrical stimulation setting is sham | Device: transcranial electrical stimulation<br>* The device is a Neoprene headcap that holds an array of padded electrodes close to the scalp to stimulate the underlying brain.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Phase I: A change in brain functional connectivity in primary cervical dystonia | A change in mean functional connectivity between the pallidum and putamen during a resting state in CD patients during inhibitory tACS targeting the sensorimotor network. | Day 1 | 
| Phase II: Improvement in Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) score | A change in TWSTRS scores following five daily sessions of inhibitory tACS. | Day 1, Day 5 |