Multichannel tDCS to Reduce Hypertonia in Patients With Prolonged DOC

Phase 1

Completed

• Conditions: Minimally Conscious State; Disorder of Consciousness; Vegetative State; Spasticity, Muscle
• Interventions: Device: sham tDCS; Device: tDCS

• Registration Number: NCT03797573
• Lead Sponsor: University of Liege

Brief 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.

Study Timeline

• Study Start: 2014-01-20
• Primary Completion: 2014-06-28
• Study Completion: 2017-12-13
• Status Verified: 2019-01
• Study First Submitted: 2019-01-03
• Study First Submitted QC: 2019-01-04
• Last Update Submitted: 2019-01-04
• Study First Posted: 2019-01-09
• Last Update Posted: 2019-01-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 17

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
sham tDCS	sham tDCS	Patients will receive sham tDCS (5 seconds of stimulation) during 20 minutes preceded and followed by a clinical assessment (Modified Ashworth Scale and Coma Recovery Scale-Revised) and neurophysiological assessment (8 channels EEG).
active tDCS	tDCS	Patients will receive tDCS (bilateral fronto-central stimulation) during 20 minutes preceded and followed by a clinical assessment (Modified Ashworth Scale and Coma Recovery Scale-Revised) and neurophysiological assessment (8 channels EEG).

Primary Outcome Measures

Name	Time	Method
Change in MAS scores	baseline and directly after tDCS (20 minutes)	Modified Ashworth Scale (MAS) will by assessed before and after tDCS (active and sham). Comparison of treatment effect (MAS score after tDCS minus before) between active and sham tDCS. The MAS is a 5 points scale going from 0 (no spasticity) and 5 (extreme spasticity).

Secondary Outcome Measures

Name	Time	Method
Change in brain oscillations	Baseline and directly after the tDCS (20 minutes)	8 channels electroencephalography (EEG) will be record before and after tDCS to record potential cortical changes induce by the stimulation. EEG power will be compared in different bandwidths (delta, theta, alpha, beta).
Change in the CRS-R total score	Baseline and directly after the tDCS (20 minutes)]	Coma Recovery Scale Revised (CRS-R) will be performed before and after tDCS (anodal and sham). Comparison of the treatment effect (CRS-R total score score after tDCS minus before) between real and sham tDCS. The CRS-R is 23 points scale with 6 sub-scales (lower scores refer to reflexes, while higher scores refer to more complex behaviors). The total score is the sum of the scores in the 6 sub-scales.

Trial Locations

Locations (1)

University of Liege; 🇧🇪 Liege, Belgium