Multichannel tDCS to Reduce Hypertonia in Patients With Prolonged DOC
Condition: Vegetative State; Minimally Conscious State; Spasticity, Muscle; Disorder of Consciousness
MeSH terms: Muscle Spasticity; Consciousness Disorders; Persistent Vegetative State; Muscle Hypertonia
Study type: Interventional
Phase: Phase 1

Summary: 
      Previous studies showed that transcranial direct current stimulation (tDCS) transiently
      improves performance of motor function in stroke patients, as well as decrease muscle
      hypertonia. 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 manage other symptoms occurring in this population of patients, such as muscle hypertonia.
      In this study, investigators will assess the effects of bilateral fronto-central tDCS on
      spasticity as measured with the Modified Ashworth Scale (MAS) and on the Coma Recovery
      Scale-Revised (CRS-R) scores in patients with DOC 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). 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, patients with DOC suffer from other invalidating dysfunctions such as
      spasticity (muscle hypertonia). In sroke patients, the inhibition of the motor cortex through
      cathodes placed over the motor region showed to reduce spasticity.

      In this study, investigators aim to assess the effect of single session of transcranial
      direct current stimulation (tDCS) over right and left fronto-central areas (using 2 anodes
      and 2 cathodes), on the level of hypertonia and the level of consciousness of patients with
      DOC, in a double blind randomized sham controlled study. The anodes will be placed over F3
      and F4, and the cathodes over C3 and C4.

      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 motor functions in healthy subjects and patients with stroke or
      Parkinson's disease.

      By reducing the activity of the motor cortex (cathodes) and increasing the activity of the
      prefrontal cortex (anodes) we expect to observe a better motor function in patients with DOC.
    

Intervention name(s): tDCS; sham tDCS
Intervention type(s): Device; Device
Intervention description(s): tDCS will be applied during 20 minutes with a current of 1 mA preceded and followed by a behavioral assessments (Modified Ashworth Scale and Coma Recovery Scale Revised) and an EEG. The anodes will be placed over F3 and F4 and the cathodes over C3 and C4.; Indentical to the active tDCS, except that the stimulation is terminated after 5 seconds.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: transcranial direct current stimulation; disorder of consciousness; muscle hypertonia; spasticity; vegetative state; minimally conscious state