Transcranial Direct Current Stimulation (tDCS) in Chronic Stroke Recovery
Condition: Stroke
MeSH terms: Stroke
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      The hypothesis of this study is that different subgroups of stroke will respond differently
      to direct current stimulation.
    

Detailed description: 
      We have tested the effectiveness of each stimulation condition: 1) anodal over the lesional
      motor cortex 2) anodal PMD (positive electrode at the dorsal premotor cortex (PMD) of the
      lesional hemisphere (first phase) or dual motor cortex stimulation (second phase), 3)
      cathodal over the contralesional motor cortex, and 4) sham in a double blind crossover design
      in chronic cortical and subcortical strokes.

      Persons in the chronic stage of recovery from stroke (>3 months) will receive each type of
      tDCS stimulation for 20 minutes concurrent with physical therapy treatments (90 minutes )
      utilizing the Armeo ®, a gravity neutral arm exercise support system for the most involved
      upper extremity which provides for task practice in a virtual reality environment, followed
      by a therapist supervised targeted hand exercise. The experimental protocol will not alter
      standard of care, will be performed after standard rehabilitation is completed. The
      experimental therapy is not part of standard care and will not be charged or reimbursed by
      the patients' insurance. Participation will be free of charge for subjects.

      We were planning to perform the study in two phases. In the first exploratory phase, we will
      conduct a short pilot study with 15 subjects to optimize and if possible simplify the
      treatment parameters for the second longer phase of the experiment. In this first phase we
      will perform one of the four different tDCS stimulation conditions concurrently with the
      physical therapy protocol on each therapy day, so that all subjects will receive all
      stimulation types in a randomized counterbalanced order. There will be a 1 day rest period in
      between sessions, making 9 days (10 days if initial evaluation is done on the day before the
      1st treatment) the total commitment time for the first phase of study.

      The outcome measures were collected before and after each session. The outcome measures
      collected after the 1 day rest provide the baseline for the next session will be also used as
      to validate the stability of the treatment effect. Subjects participating in the first part
      of the study will be offered the option to participate in the second longer phase of the
      study. (please see table under study procedures)

      In the second phase of the experiment we will perform only the promising stimulation
      paradigms plus sham from the first part of the experiment in a random, counterbalanced order
      on up to 30 chronic stroke subjects. If in the initial phase there are no differences found
      between stimulation types in the cortical vs subcortical patient groups then all 3
      stimulation paradigms will be performed in the second phase.

      Based on our preliminary data, we will perform the following paradigms in the second phase:
      1) sham 2) dual stimulation 3) optimized tDCS in a randomized counterbalanced order. The
      optimized tDCS will be determined during a test session prior to the first treatment where
      the tDCS montage producing the best behavioral response will be used during therapy. Subjects
      will perform this under IRB approved study # STU 102013-085.

      The patient time commitment in the second phase is 18 weeks, where subjects will have 3 x 1
      weeks long treatment (5 weekdays) sessions with 5 week inter-treatment "rest period". The
      blinded tester will perform a final outcome evaluation 5 weeks after the end of the last
      session. (please see table under study procedures)

      Total number of potential enrolled subjects for both phases will be approximately 45 [Phase 1
      (15) + Phase 2 (30)].

      The stepwise design will enable us to optimize study time commitment and expenses for both
      patients and researchers while maximizing clinical/scientific gain.
    

Intervention name(s): tDCS
Intervention type(s): Device
Intervention description(s): tDCS and sham will be applied in random order during standardized occupational therapy
Other intervention name(s): transcranial direct current stimulation
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: stroke; recovery; tDCS; direct current; electric stimulation