Transcranial Direct Current Stimulation in Patients With Disorders of Consciousness

Study Overview
=================
Brief Summary
-----------------
Previous studies showed that anodal transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal (DLPF) cortex transiently improves performance of memory and attention. Investigator assessed the effects of left DLPF-tDCS on Coma Recovery Scale-Revised (CRS-R) scores in severely brain damaged patients with disorders of consciousness in a double-blind sham-controlled experimental design.

Detailed Description
-----------------
Following severe brain damage and coma, some patients may remain in a vegetative state (VS) or minimally conscious state (MCS). At present, there are no evidence-based guidelines regarding the treatment of patients with disorders of consciousness (DOC). Investigator aim to assess the effect of single session anodal (i.e., excitatory) transcranial direct current stimulation (tDCS) of the left dorsolateral prefrontal cortex (DLPF) on the level of consciousness in DOC patients in a double blind randomized sham controlled study. tDCS is a form of safe non-invasive cortical stimulation, modulating cortical excitability at stimulation sites via weak polarizing currents, previously reported to transiently improve working memory and attention by stimulating the left DLPF in healthy subjects and patients with stroke, Parkinson's or Alzheimer's disease.

Official Title
-----------------
Transcranial Direct Current Stimulation in Patients With Disorders of Consciousness: a Sham-controlled Randomised Double Blind Study

Conditions
-----------------
Vegetative State, Minimally Conscious State, Disorders of Consciousness

Intervention / Treatment
-----------------
* Device: Anodal tDCS
* Device: sham tDCS


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: post-comatose patients patients in vegetative/unresponsive or minimally conscious state patients with stable cardiorespiratory parameters patients free of sedative drugs and Na+ or Ca++ channel blockers (e.g., carbamazepine) or NMDA receptor antagonists (e.g., dextromethorphan) Exclusion Criteria: premorbit neurology antecedent patients in coma or <1week after the acute brain insult patients with a metallic cerebral implant or a pacemaker (in line with the safety criteria for tDCS in humans)

Ages Eligible for Study
-----------------
Minimum Age: 15 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Anodal tDCS<br>Patients received anodal tDCS (on DLPF cortex) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) | Device: Anodal tDCS<br>* patients received anodal tDCS (on PFDL cortex) during 20 minutes preceded and followed by a behavioral assessment (Coma Recovery Scale Revised)<br>|
| Sham Comparator: sham tDCS<br>Patient received a sham tDCS (5sec of stimulation). The device runs during 20minutes and the anode was placed over the DLPF cortex. A behavioral assessment preceded and followed the stimulation. | Device: sham tDCS<br>* Patient received a sham tDCS (5sec of stimulation). The device runs during 20minutes and the anode was placed over the DLPF cortex. A behavioral assessment preceded and followed the stimulation.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in CRS-R Total Scores | At the group level, assess the modification of CRS-R total scores in anodal tDCS as compared to sham stimulation in VS/UWS and MCS populations The Coma Recovery Scale Revised (CRS-R) is a behavioral scale performed at the patient's bedside. It consists of 23 hierarchically arranged items that comprise 6 subscales addressing auditory, visual, motor, verbal, communication, and arousal functions. Scoring is based on the presence or absence of specific behavioral responses to sensory stimuli administered in a standardized manner. Maximum scores of each subscale are summed to obtain the total score (from 0 to 23). The lowest item on each subscale represents reflexive activity, whereas the highest items represent cognitively mediated behaviors. | Baseline and directly after the tDCS (20 minutes) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of Diagnosis on the Results |  | participants will be followed for the duration of 1 year | 
| Influence of Etiology on the Results |  | participants will be followed for the duration of 1 year | 
| Influence of Time Since Insult on the Results |  | participants will be followed for the duration of 1 year | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
vegetative state, minimally conscious state, disorders of consciousness, transcranial direct current stimulation