Transcranial Alternating Current Stimulation (tACS) in Patients With Ataxia

Study Overview
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Brief Summary
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The aim of the study is to evaluate the effects on motor and cognitive performance of transcranial alternating current stimulation (tACS) compared to transcranial direct current stimulation (tDCS) and placebo stimulation (sham) in patients with neurodegenerative ataxia to identify a possible rehabilitation protocol.

Official Title
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Interventional Cross-over Study to Evaluate the Efficacy on Motor and Cognitive Performance of Transcranial Alternating Current Stimulation (tACS) in Patients With Neurodegenerative Ataxia

Conditions
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Ataxia, Spinocerebellar Ataxias, Multiple System Atrophy, Ataxia With Oculomotor Apraxia, CANVAS

Intervention / Treatment
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* Device: Transcranial stimulation over the cerebellar hemispheres


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a cerebellar syndrome and quantifiable cerebellar atrophy Exclusion Criteria: Severe head trauma in the past History of seizures History of ischemic stroke or hemorrhage Pacemaker Metal implants in the head/neck region Severe comorbidity Intake of illegal drugs Pregnancy

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Transcranial direct current stimulation (tDCS)<br>Single session of anodal tDCS at 2 mA over the cerebellar hemispheres | Device: Transcranial stimulation over the cerebellar hemispheres<br>* Single session of Transcranial stimulation over the cerebellar hemispheres<br>|
| Active Comparator: Transcranial alternate current stimulation (tDCS)<br>Single session of gamma tACS (50 Hz) at 3 mA over the cerebellar hemispheres | Device: Transcranial stimulation over the cerebellar hemispheres<br>* Single session of Transcranial stimulation over the cerebellar hemispheres<br>|
| Sham Comparator: Placebo stimulation (sham)<br>Single session of sham tDCS over the cerebellar hemispheres | Device: Transcranial stimulation over the cerebellar hemispheres<br>* Single session of Transcranial stimulation over the cerebellar hemispheres<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the International Cooperative Ataxia Rating Scale (ICARS) Score From Baseline | International Cooperative Ataxia Rating Scale (ICARS): semi-quantitative 100-point scale, yielding a total score of 0 (no ataxia) to 100 (most severe ataxia). | Baseline (immediately before the intervention) - Immediately after the intervention | 
| Change in the Scale for the Assessment and Rating of Ataxia (SARA) Score From Baseline | Scale for the Assessment and Rating of Ataxia (SARA): 8-item performance based scale, yielding a total score of 0 (no ataxia) to 40 (most severe ataxia). | Baseline (immediately before the intervention) - Immediately after the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Cerebellar Brain Inhibition (CBI) Measurements From Baseline | Cerebellar brain inhibition (CBI) is expressed as motor evoked potential amplitude (average of 10 recordings). Lower values reflect higher inhibition and thus reduced impairment. | Baseline (immediately before the intervention) - Immediately after the intervention | 
| Change in Timed Up and Go Test Duration From Baseline | Time (in seconds) that a person takes to rise from a chair, walk three meters, turn around 180 degrees, walk back to the chair, and sit down while turning 180 degrees, assessed with gait sensors. | Baseline (immediately before the intervention) - Immediately after the intervention | 
| Change in Walking Cadence From Baseline | Average Left and Right Steps/Minute during a 60 seconds walk, assessed with gait sensors. | Baseline (immediately before the intervention) - Immediately after the intervention | 
| Change in 360° Turn From Baseline | Velocity (Number of Degrees/sec) in making a 360° turn, assessed with gait sensors | Baseline (immediately before the intervention) - Immediately after the intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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transcranial direct current stimulation, transcranial alternate current stimulation, spinocerebellar ataxia, cerebellar ataxia