Fronto-parietal tDCS in Severely Brain Injured Patients With Disorders of Consciousness

University of Liege

Status: Completed

Conditions: Vegetative State; Minimally Conscious State; Disorders of Consciousness

Treatments: Device: Anodal tDCS; Device: Sham tDCS

Study type: Interventional

Funder types: Other

Identifiers

NCT02626403

2014/280

Details and patient eligibility

About

Previous studies showed that anodal transcranial direct current stimulation (tDCS) transiently improves performance of memory and attention. In severely brain injured patients with disorders of consciousness (DOC), a single stimulation over the left dorsolateral prefrontal cortex has shown to improve patients' sign of consciousness. Nevertheless, other brain areas could be stimulated in order to increase the number of responders. In this study, investigators will assess the effects of bilateral fronto-parietal tDCS on Coma Recovery Scale-Revised (CRS-R) scores in patients with DOC in a double-blind sham-controlled experimental design.

Full 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). A previous study showed that a single stimulation (using transcranial direct current stimulation - tDCS) of the left prefrontal cortex induces an behavioral improvement in some patients in DOC. Nevertheless, only 43% of patients in MCS responded to the stimulation. Therefore, it is needed to find new protocols to increase the number of responders and improve the effect of tDCS in patients with DOC.

In this study, investigators aim to assess the effect of single session anodal (i.e., excitatory) transcranial direct current stimulation (tDCS) over right and left fronto-temporal cortices (using 4 anodes and 4 cathodes), on the level of consciousness of patients with DOC, in a double blind randomized sham controlled study. The anodes will be placed over F3, F3, CP5 and CP6.

tDCS is a form of safe non-invasive cortical stimulation, modulating cortical excitability under the electrodes, via weak polarizing currents. It has been reported that anodal tDCS transiently improves working memory and attention by stimulating the left DLPF in healthy subjects and patients with stroke, Parkinson's or Alzheimer's disease. By increasing the surface of the stimulated area, it is expected to increase the number of responders as patients' brain lesion are very heterogeneous and widespread.

Enrollment: 46 patients

Sex: All

Ages: 16 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• post comatose patients
• patients 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)

Exclusion criteria

• premorbid neurology antecedent
• patients in coma
• patients < 28 days after the acute brain injury
• patients with a metallic cerebral implant
• cranioplasty
• shunt

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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46 participants in 2 patient groups

anodal tDCS

Active Comparator group

Description:

Patients will receive anodal tDCS (bilateral fronto-parietal stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (8 channels EEG).

Treatment:

Device: Anodal tDCS

sham tDCS

Sham Comparator group

Description:

Patients will receive sham tDCS (15 second of stimulation) during 20 minutes preceded and followed by a clinical assessment (Coma Recovery Scale-Revised) and neurophysiological assessment (8 channels EEG).

Treatment:

Device: Sham tDCS