Effects of Bihemispheric Transcranial Direct Current Stimulation Combined With Repetitive Peripheral Nerve...

Transcranial direct current stimulation (tDCS) can change the excitability of the central nervous system and contribute to motor recovery of stroke patients. The aim of our study was to examine the short- and long-term effects of real versus sham bihemispheric tDCS combined with repetitive peripheral nerve stimulation in patients with acute stroke and a severe motor impairment.

The study was prospective, randomized, double blind, and placebo controlled. Nineteen acute stroke patients (ischemic and hemorrhagic) with upper limb Fugl-Meyer mean score of <19 were randomized in two groups: one group received five consecutive daily sessions of anodal tDCS over the affected hemisphere and cathodal over unaffected hemisphere combined with repetitive peripheral nerve stimulation and the other received sham tDCS associated to repetitive peripheral nerve stimulation. Clinical and neurophysiological assessment was applied before tDCS, 5 days after tDCS, and 3, 6, and 12 months after tDCS.

There were significant time-related changes in both groups of patients in motor evoked potentials, somatosensory evoked potentials, Hmax:Mmax ratio, upper limb Fugl-Meyer scores, and Modified Ashworth scales scores ( P < 0.05). However, no significant differences between groups were present at any time ( P > 0.05).

Bihemispheric tDCS and repetitive peripheral nerve stimulation with the parameters of our study did not add significant short- or long-term clinical improvement or change in neurophysiological data in severe acute stroke patients in comparison to sham stimulation. The severity of motor impairment in stroke patients may influence a possible response to an interventional tDCS treatment.