Characterizing the Mechanisms of Central and Peripheral Forms of Neurostimulation in Chronic Dysphagic Stroke Patients

• DOI: 10.1016/j.brs.2013.09.005
• Publication Date: 2013-10-10T14:58:30Z
• Authors: Emilia Michou; Satish Mistry; Samantha Jefferson; Pippa Tyrrell; Shaheen Hamdy
• Keywords: Neurostimulation; Peripheral nerve stimulation; Stroke

Swallowing problems following stroke may result in increased risk of aspiration pneumonia, malnutrition, and dehydration.Our hypothesis was that three neurostimulation techniques would produce beneficial effects on chronic dysphagia through a common brain mechanism predict behavioral response.In 18 dysphagic patients (mean age: 66 ± 3 years, female, time-post-stroke: 63 15 weeks [±SD]), pharyngeal electromyographic responses were recorded after single-pulse transcranial magnetic stimulation (TMS) over the motor cortex, to measure corticobulbar excitability before, immediately, 30 min, real sham applications neurostimulation. Patients randomized single session either: electrical (PES), paired associative (PAS) or repetitive TMS (rTMS). Penetration-aspiration scores bolus transfer timings assessed before both interventions using videofluoroscopy.Corticobulbar cortex beneficially modulated by PES, PAS lesser extent rTMS, with functionally relevant changes unaffected hemisphere. Following combining results neurostimulation, an overall increase hemisphere (P = .005, F1,17 10.6, ANOVA) associated 15% reduction z -2.79) observed compared sham.In this mechanistic study, projection correlated improvement swallowing safety .001, rho -.732), but modality-specific differences observed. Paradigms providing peripheral input favored change neurophysiological outcome measures patients. Further larger cohort studies are imperative.