Effect of cerebellar transcranial magnetic stimulation with double-cone coil on dysphagia after subacute infratentorial stroke: A randomized, single-blinded, controlled trial

Background: A 10-Hz cerebellar repetitive transcranial magnetic stimulation (rTMS) could increase corticobulbar tract excitability in healthy individuals. However, its clinical efficacy for poststroke dysphagia (PSD) remains unclear. Objective: To investigate the effectiveness of 10-Hz cerebellar rTMS in PSD patients with infratentorial stroke (IS).Methods: In this single-blinded, randomized controlled trial, 42 PSD patients with subacute IS were allocated to three groups: bilateral cerebellar rTMS (biCRB-rTMS), unilateral cerebellar rTMS (uniCRB-rTMS), or sham-rTMS. The stimulation parameters were 5 trains of 50 stimuli at 10 Hz with an interval of 10 s at 90% of the thenar resting motor threshold (RMT). The Functional Oral Intake Scale (FOIS) was assessed at T0 (baseline), T1 (day 0 after intervention), and T2 (day 14 after intervention), whereas the Dysphagia Outcome and Severity Scale (DOSS), Penetration Aspiration Scale (PAS), and neurophysiological parameters were evaluated at T0 and T1.Results: Significant time and intervention interaction effects were observed for the FOIS score (F = 3.045, p = 0.022). The changes in the FOIS scores at T1 and T2 were both significantly higher in the biCRB-rTMS group than in the sham-rTMS group (p < 0.05). The uniCRB-rTMS and biCRB-rTMS groups demonstrated greater changes in the DOSS and PAS at T1, compared with the sham-rTMS group (p < 0.05). Bilateral corticobulbar tract excitability partly increased in the biCRB-rTMS and uniCRB-rTMS groups at T1, compared with T0. The percent changes in corticobulbar tract excitability parameters at T1 showed no difference among three groups.Conclusions: A 10-Hz bilateral cerebellar rTMS is a promising, noninvasive treatment for subacute infratentorial PSD.