Contralesional Cathodal Transcranial Direct Current Stimulation Does Not Enhance Upper Limb Function in Subacute Stroke: A Pilot Randomized Clinical Trial.

Transcranial direct current stimulation (tDCS) has the potential to improve upper limb motor outcomes after stroke. According to the assumption of interhemispheric inhibition, excessive inhibition from the motor cortex of the unaffected hemisphere to the motor cortex of the affected hemisphere may worsen upper limb motor recovery after stroke. We evaluated the effects of active cathodal tDCS of the primary motor cortex of the unaffected hemisphere (ctDCSM1UH) compared to sham, in subjects within 72 hours to 6 weeks post ischemic stroke. Cathodal tDCS was intended to inhibit the motor cortex of the unaffected hemisphere and hence decrease the inhibition from the unaffected to the affected hemisphere and enhance motor recovery. We hypothesized that motor recovery would be greater in the active than in the sham group. In addition, greater motor recovery in the active group might be associated with bigger improvements in measures in activity and participation in the active than in the sham group. We also explored, for the first time, changes in cognition and sleep after ctDCSM1UH. Thirty subjects were randomized to six sessions of either active or sham ctDCSM1UH as add-on interventions to rehabilitation. The NIH Stroke Scale (NIHSS), Fugl-Meyer Assessment of Motor Recovery after Stroke (FMA), Barthel Index (BI), Stroke Impact Scale (SIS), and Montreal Cognitive Assessment (MoCA) were assessed before, after treatment, and three months later. In the intent-to-treat (ITT) analysis, there were significant GROUP∗TIME interactions reflecting stronger gains in the sham group for scores in NIHSS, FMA, BI, MoCA, and four SIS domains. At three months post intervention, the sham group improved significantly compared to posttreatment in FMA, NIHSS, BI, and three SIS domains while no significant changes occurred in the active group. Also at three months, NIHSS improved significantly in the sham group and worsened significantly in the active group. FMA scores at baseline were higher in the active than in the sham group. After adjustment of analysis according to baseline scores, the between-group differences in FMA changes were no longer statistically significant. Finally, none of the between-group differences in changes in outcomes after treatment were considered clinically relevant. In conclusion, active CtDCSM1UH did not have beneficial effects, compared to sham. These results were consistent with other studies that applied comparable tDCS intensities/current densities or treated subjects with severe upper limb motor impairments during the first weeks post stroke. Dose-finding studies early after stroke are necessary before planning larger clinical trials.

Boasquevisque DS ，Servinsckins L ，de Paiva JPQ ，Dos Santos DG ，Soares P ，Pires DS ，Meltzer JA ，Plow EB ，de Freitas PF ，Speciali DS ，Lopes P ，Peres MFP ，Silva GS ，Lacerda S ，Conforto AB ... -  《-》

The impact of transcranial direct current stimulation (tDCS) combined with modified constraint-induced movement therapy (mCIMT) on upper limb function in chronic stroke: a double-blind randomized controlled trial.

Rocha S ，Silva E ，Foerster Á ，Wiesiolek C ，Chagas AP ，Machado G ，Baltar A ，Monte-Silva K ... -  《-》

Effects of transcranial direct current stimulation with virtual reality on upper limb function in patients with ischemic stroke: a randomized controlled trial.

Yao X ，Cui L ，Wang J ，Feng W ，Bao Y ，Xie Q ... -  《Journal of NeuroEngineering and Rehabilitation》

Comparison of Neuroplastic Responses to Cathodal Transcranial Direct Current Stimulation and Continuous Theta Burst Stimulation in Subacute Stroke.

To investigate the effects of cathodal transcranial direct current stimulation (tDCS) and continuous theta burst stimulation (cTBS) on neural network connectivity and motor recovery in individuals with subacute stroke. Double-blinded, randomized, placebo-controlled study. University hospital rehabilitation unit. Inpatients with stroke (N=41; mean age, 65y; range, 28-85y; mean weeks poststroke, 5; range, 2-10) with resultant paresis in the upper extremity (mean Fugl-Meyer score, 14; range, 3-48). Subjects with stroke were randomly assigned to neuronavigated cTBS (n=14), cathodal tDCS (n=14), or sham transcranial magnetic stimulation/sham tDCS (n=13) over the contralesional primary motor cortex (M1). Each subject completed 9 stimulation sessions over 3 weeks, combined with physical therapy. Brain function was assessed with directed and nondirected functional connectivity based on high-density electroencephalography before and after stimulation sessions. Primary clinical end point was the change in slope of the multifaceted motor score composed of the upper extremity Fugl-Meyer Assessment score, Box and Block test score, 9-Hole Peg Test score, and Jamar dynamometer results between the baseline period and the treatment time. Neither stimulation treatment enhanced clinical motor gains. Cathodal tDCS and cTBS induced different neural effects. Only cTBS was able to reduce transcallosal influences from the contralesional to the ipsilesional M1 during rest. Conversely, tDCS enhanced perilesional beta-band oscillation coherence compared with cTBS and sham groups. Correlation analyses indicated that the modulation of interhemispheric driving and perilesional beta-band connectivity were not independent mediators for functional recovery across all patients. However, exploratory subgroup analyses suggest that the enhancement of perilesional beta-band connectivity through tDCS might have more robust clinical gains if started within the first 4 weeks after stroke. The inhibition of the contralesional M1 or the reduction of interhemispheric interactions was not clinically useful in the heterogeneous group of subjects with subacute stroke. An early modulation of perilesional oscillation coherence seems to be a more promising strategy for brain stimulation interventions.

Nicolo P ，Magnin C ，Pedrazzini E ，Plomp G ，Mottaz A ，Schnider A ，Guggisberg AG ... -  《-》

Effects of anodal transcranial direct current stimulation over the contralesional hemisphere on motor recovery in subacute stroke patients with severe upper extremity hemiparesis: Study protocol for a randomized controlled trial.

Lee SH ，Kim WS ，Park J ，Kim J ，Paik NJ ... -  《-》