Short term effects of anodal cerebellar vs. anodal cerebral transcranial direct current stimulation in stroke patients, a randomized control trial

Abstract

BackgroundBalance and gait impairments are major motor deficits in stroke patients that require intensive neuro-rehabilitation. Anodal transcranial direct current stimulation is a neuro-modulatory technique recently used in stroke patients for balance and gait improvement. Majority of studies focusing on tDCS have assessed its effects on cerebral motor cortex and more recently cerebellum as well but to our best knowledge the comparison of stimulating these two regions in stroke patients is not investigated so far.ObjectiveThe current study aimed to compare the effect of anodal transcranial direct current stimulation on cerebellar and cerebral motor cortex M1 in stroke patients.Materials and methodsThis double-blinded, parallel, randomized, sham controlled trial included 66 patients with a first-ever ischemic stroke were recruited into three groups; Cerebellar stimulation group (CbSG), M1 Stimulation Group (MSG), and Sham stimulation group (SSG). A total of three sessions of anodal transcranial direct current stimulation were given on consecutive days in addition to non-immersive virtual reality using Xbox 360 with kinect. Anodal tDCS with an intensity of 2 mA was applied for a duration of 20 min. Primary outcome measures berg balance scale (BBS), timed up and go test (TUG), BESTest Balance Evaluation–Systems Test (BESTest) and secondary outcomes measures montreal cognitive assessment (MoCA), mini mental state examination (MMSE), Johns Hopkins Fall Risk Assessment Tool (JHFRAT), twenty five feet walk test (25FWT), six minute walk test (6MWT), and tDCS Adverse Effects was assessed before initiation of treatment (T0) and at the end of third session of stimulation (T1).ResultsThe results of between group’s analysis using mean difference showed a significant difference with p-value <0.05 for balance (BBS, TUG, BESTest), walking ability (6MWT, 25FWT), risk of fall (JHFRAT). Cognitive function did not show any significant change among the groups for MoCA with p-value >0.05 but MMSE was improved having significant p-value (p = 0.013). However, 6MWT and 25FWT showed non-significant results for both between group and within group analysis. In pairwise comparison both the cerebellar and cerebral stimulation groups showed Significant difference with p-value <0.05 in comparison to sham stimulation; BBS (cerebellar vs. sham p ≤ 0.001, cerebral vs. sham p = 0.011), TUG (cerebellar vs. sham p = 0.001, cerebral vs. sham p = 0.041), Bestest (cerebellar vs. sham p = 0.007, cerebral vs. sham p = 0.003). Whereas for JHFRAT only cerebellar stimulation in comparison to sham and motor cortex stimulation showed significant improvements (cerebellar vs. M1 p = 0.037, cerebellar vs. sham p = 0.037). MMSE showed significant improvement in M1 stimulation (M1 vs. cerebellar p = 0.036, M1 vs. sham p = 0.011).ConclusionFindings of the study suggest anodal tDCS stimulation of the cerebellum and cerebral motor cortex both improves gait, balance and risk of fall in stroke patients. However, both stimulation sites do not induce any notable improvement in cognitive function. Effects of both stimulation sites have similar effects on mobility in stroke patients.

Effects of Cerebellar Non-Invasive Stimulation on Neurorehabilitation in Stroke Patients: An Updated Systematic Review

“…The review included twenty-one randomized controlled trials (RCTs) and one pilot study [ 35 ]. Among the RCTs, fifteen were parallel-design [ 29 , 30 , 31 , 32 , 34 , 36 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ], while six were crossover-design [ 33 , 48 , 49 , 50 , 51 , 52 ]. Except for the pilot study, all RCT experiments utilized random assignment and allocation concealment.…”

“…Except for the pilot study, all RCT experiments utilized random assignment and allocation concealment. Fifteen RCTs blinded both participants and outcome assessors [ 29 , 30 , 32 , 33 , 34 , 36 , 39 , 40 , 41 , 43 , 44 , 46 , 47 , 48 , 51 ], while two RCTs, focusing on aphagia, were single-blinded examiner studies [ 27 , 33 ]. In two studies, blinding was applied to participants, but the blinding status of the outcome assessors was not mentioned in the articles [ 49 , 52 ].…”

“…These reviews have not thoroughly examined the impact of cerebellar NIBS on a range of post-stroke neurologic deficits. Moreover, studies post-2022 have highlighted the efficacy of cerebellar NIBS in treating dysphagia [ 29 , 30 , 31 , 32 ], fine motor dysfunction [ 33 , 34 ], aphasia [ 35 ], and cognitive impairment [ 36 ] after stroke, showcasing the potential of cerebellar stimulation beyond treating dyskinesia. Thus, an updated systematic review that comprehensively evaluates the diverse stimulation parameters of NIBS for varying post-stroke sequelae is essential to promote its broader application in stroke rehabilitation.…”

Exploring the Differential Effects of Transcranial Direct Current Stimulation: A Comparative Analysis of Motor Cortex and Cerebellar Stimulation

“…The choice of stimulation has largely been based on specific motor deficits and the stage of stroke. On one hand, anodal cerebellar is compared to anodal cerebral tDCS to assess improved gait, balance, and risk of fall in stroke patients [ 43 ]. On the other hand, cerebellar tDCS is used as an effective and safe treatment to promote recovery of upper limb motor function [ 44 ] or functional balance in chronic stroke patients [ 45 ].…”

Comparison of a single session of tDCS on cerebellum vs. motor cortex in stroke patients: a randomized sham-controlled trial

“…Our research team has planned two clinical studies to examine the effects of single and short-term anodal tDCS on stroke patients’ gait and lower limb function. After short-term stimulation, both stimulation sites were effective [ 48 ]. This article discusses single-session outcomes.…”