Prefontal tDCS in Patients With Disorders of Consciousness: Neurophysiological and Behavioural Outcomes

Sponsor

University of Liege (Other)

Overall Status

Completed

CT.gov ID

NCT03823508

Collaborator

(none)

Enrollment

Location

Arms

Actual Duration (Months)

0.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Non-invasive brain stimulations techniques have recently shown promising results in patients with disorders. Notably, transcranial direct current stimulation (tDCS) applied over the left dorsolateral prefrontal cortex has proved to be effective in improving signs of consciousness in about 50% of patients in MCS either after a single stimulation or after repeated sessions. However, brain mechanisms underlying tDCS effects remain poorly understood. Here we aim to assess the effects of prefrontal tDCS on neurophysiological (i.e., electroencephalography - EEG - primary outcome) and behavioral (secondary outcome) measures in severely brain-injured patients with DOC.

Condition or Disease	Intervention/Treatment	Phase
Vegetative State Minimally Conscious State Disorder of Consciousness	Device: anodal tDCS Device: sham tDCS	N/A

Detailed Description

Currently, therapeutic options for severely brain-injured patients with disorders of consciousness (DOC), including patients in unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), are limited and still need to be improved to influence long-term outcomes. Non-invasive brain stimulations (NIBS) techniques have recently shown promising results in DOC. Notably, transcranial direct current stimulation (tDCS) applied over the left dorsolateral prefrontal cortex has proved to be effective in improving signs of consciousness in about 50% of patients in MCS either after a single stimulation or after repeated sessions. However, brain mechanisms underlying tDCS effects remain poorly understood.In the present protocol, the investigators will assess the effects of prefrontal tDCS on neurophysiological (i.e., electroencephalography - EEG - primary outcome) and behavioral (secondary outcome) measures in severely brain-injured patients with DOC in a double-blind sham-controlled design. One anodal and one sham tDCS will be delivered in a randomized order in chronic (>28 days post-onset) severely brain-damaged patients. The stimulation will have an intensity of 2 mA and will last 20 minutes. The anode will be placed on the left dorsolateral prefrontal cortex and the cathode on the right supraorbital region. Ten minutes of high-density EEG will be recorded using a 256-channel saline electrode net (Electrical Geodesics) directly before and after each tDCS session. Behavioral assessments will be performed using the Coma Recovery Scale-Revised before and after each session by an investigator blinded to the treatment allocation.

Study Design

Study Type:

Interventional

Actual Enrollment :

15 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)

Primary Purpose:

Treatment

Official Title:

Prefontal tDCS in Patients With Disorders of Consciousness: Neurophysiological and Behavioural Outcomes

Actual Study Start Date :

Jan 1, 2018

Actual Primary Completion Date :

Jun 1, 2019

Actual Study Completion Date :

Jun 1, 2019

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: anodal tDCS Patients will receive anodal tDCS (left dorsolateral prefrontal stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (256 channels EEG).	Device: anodal tDCS Patients will receive anodal tDCS during 20 minutes preceded and followed by a behavioral assessment (Coma Recovery Scale Revised) and a high density EEG. The anode will be placed over F3 in order to stimulate the left dorsolateral prefrontal cortex and the cathode over the right supraorbital area.
Placebo Comparator: sham tDCS Patients will receive sham tDCS (15 secondes of stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (256 channels EEG).	Device: sham tDCS Identical to anodal tDCS, except that the stimulation will be stopped after 15 seconds.

Arm

Intervention/Treatment

Active Comparator: anodal tDCS

Patients will receive anodal tDCS (left dorsolateral prefrontal stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (256 channels EEG).

Device: anodal tDCS

Patients will receive anodal tDCS during 20 minutes preceded and followed by a behavioral assessment (Coma Recovery Scale Revised) and a high density EEG. The anode will be placed over F3 in order to stimulate the left dorsolateral prefrontal cortex and the cathode over the right supraorbital area.

Placebo Comparator: sham tDCS

Patients will receive sham tDCS (15 secondes of stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (256 channels EEG).

Device: sham tDCS

Identical to anodal tDCS, except that the stimulation will be stopped after 15 seconds.

Outcome Measures

Primary Outcome Measures

Change in the CRS-R scores [Baseline and directly after the tDCS (20 minutes)]
CRS-R will be performed before and after tDCS (anodal and sham). Comparison of the treatment effect (CRS-R total score after tDCS minus before) between real and sham tDCS

Secondary Outcome Measures

Change in EEG [Baseline and directly after the tDCS (20 minutes)]
256 channels EEG will be record before and after tDCS to record potential cortical changes induce by the stimulation.
Change in the vigilance level [Baseline and directly after the tDCS (20 minutes)]
Ocular parameters will be record using glasses before and after tDCS to record potential change of the vigilance level

Eligibility Criteria

Criteria

Ages Eligible for Study:

16 Years to 75 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

post-comatose patients
patients in vegetative state/unresponsive wakefulness syndrome or in minimally conscious state
patients with stable condition
patients free of sedative drugs and Na+ or Ca++ blockers (e.g., carbamazepine) or NMDA receptor antagonist (e.g., dextromethorphan)