Transcranial Direct Current Stimulation Combined Sensory Modulation Intervention in Chronic Stroke Patients
Status:
Completed
Trial end date:
2015-06-01
Target enrollment:
Participant gender:
Summary
Background and purpose:
About 30% of people with stroke suffered from severe long-term upper extremity （UE） motor
impairment. Severe UE impairment, especially dysfunction of hand, can greatly impact stroke
patients' daily living independence and quality of life. However, treatment effect of current
interventions is still limited. Nick Ward and Leonardo Cohen suggested 5 intervention
strategies for stroke motor recovery: （1） reduction of somatosensory input from the intact;
（2） increase in somatosensory input from the paretic; （3） anesthesia of a body part proximal
to the paretic hand; （4） activity within the affected motor cortex may be up-regulated; （5）
activity within the intact motor cortex may be down-regulated. Recent studies have shown each
strategy to be effective in stroke patients with mild or moderate UE impairment. However,
evidence for people with severe UE impairment after stroke remains unclear. Since research
has found a greater effect for combined strategies than a single strategy, this proposal
develops a combined intervention with the above 5 strategies, named "transcranial direct
current stimulation （tDCS） combined sensory modulation intervention". This intervention is
expected to be most effective for people with severe UE impairment after stroke.
In addition, neuroimaging can provide in vivo information about the brain plasticity which
underpinning the motor recovery after stroke. However, image indexes that can be used in
stroke patients with severe UE impairment remained examined. Therefore, this proposal has 3
aims: （1） to examine the treatment effect of the "tDCS combined sensory modulation
intervention" in stroke patients with severe UE impairment; （2） to examine the underline
mechanism of the efficacy of "tDCS combined sensory modulation intervention" using
neuroimaging technology.
Methods:
This study is a double-blinded randomized controlled trial which will recruit 60 people who
have had stroke onset more than 6 months and have severe UE motor impairment. All
participants will be randomly assigned into 2 groups. The experimental group will be given
the "tDCS combined sensory modulation intervention", combining bilateral tDCS stimulation,
anesthesia techniques and repetitive passive motor training. The control group is given sham
tDCS, sham anesthesia and repetitive passive motor training. Each group will be evaluated for
outcomes at 4 time points （i.e. baseline, post-intervention, 3 months and 6months
post-intervention）. The immediate and long-term effect of the interventions will be examined.
Primary outcome indicators include upper extremity impairment measures. Secondary outcome
measures include upper extremity function, activities of daily living function, functional
Magnetic Resonance Imaging （fMRI）, and corticospinal tract structural integrity using
diffusion spectrum imaging （DSI）. Fifteen subjects of each group will be assessed 2 times
（i.e., prior to the intervention and after the intervention） for fMRI and DSI scan.
Anticipatory results and contributions:
The results of the studies are expected to present a potentially effective intervention for
stroke patients with severe impaired UE motor. Imaging evidence of brain plasticity for this
particular intervention is also provided. The results will contribute to our understanding of
brain plasticity for UE motor recovery after stroke. Findings from this proposal may help
researchers and clinicians choose or develop interventions that are optimal to their clients
individually.