Abstract
Objective
To assess the efficacy of transcranial direct current stimulation (tDCS) on improving
consciousness in patients with persistent unresponsive wakefulness syndrome (UWS)
(previously termed persistent vegetative state [PVS]) or in a minimally conscious
state (MCS).
Design
Prospective, case series trial with follow-up at 12 months.
Setting
General and research hospital.
Participants
Inpatients in a PVS/UWS or MCS (N=10; 7 men, 3 women; age range, 19–62y; etiology:
traumatic brain injury, n=5; anoxia, n=4; postoperative infarct, n=1; duration of
PVS/UWS or MCS range, 6mo–10y). No participant withdrew because of adverse effects.
Intervention
All patients received sham tDCS for 20 minutes per day, 5 days per week, for 1 week,
and real tDCS for 20 minutes per day, 5 days per week, for 2 weeks. An anodal electrode
was placed over the left primary sensorimotor cortex or the left dorsolateral prefrontal
cortex, with cathodal stimulation over the right eyebrow. One patient in an MCS received
a second round of 10 tDCS sessions 3 months after initial participation.
Main Outcome Measure
JFK Coma Recovery Scale-Revised.
Results
All patients in an MCS showed clinical improvement immediately after treatment. The
patient who received a second round of tDCS 3 months after initial participation showed
further improvement and emergence into consciousness after stimulation, with no change
between treatments. One patient who was in an MCS for <1 year before treatment (postoperative
infarct) showed further improvement and emergence into consciousness at 12-month follow-up.
No patient showed improvement before stimulation. No patient in a PVS/UWS showed immediate
improvement after stimulation, but 1 patient who was in a PVS/UWS for 6 years before
treatment showed improvement and change of status to an MCS at 12-month follow-up.
Conclusions: tDCS seems promising for the rehabilitation of patients with severe disorders of
consciousness. Severity and duration of pathology may be related to the degree of
tDCS' beneficial effects.
Keywords
List of abbreviations:
CRS-R (Coma Recovery Scale-Revised), DLPFC (dorsolateral prefrontal cortex), FDG-PET ([18F]-fluorodeoxyglucose positron emission tomography), fMRI (functional magnetic resonance imaging), MCS (minimally conscious state), MCS– (minimally conscious state minus), MCS+ (minimally conscious state plus), PVS (persistent vegetative state), rCBF (regional cerebral blood flow), TBI (traumatic brain injury), tDCS (transcranial direct current stimulation), UWS (unresponsive wakefulness syndrome), VS (vegetative state)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: September 13, 2013
Footnotes
Supported in part by the HIVE project (http://hive-eu.org), a Future and Emerging Technologies program within the 7th Framework Programme for Research of the European Commission (grant no. 222079) and the Hellenic Center for Neurosurgical Research “Prof. Petros Kokkalis.”
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.
Identification
Copyright
© 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
