Repetitive Transcranial Magnetic Stimulation Protocols for Swallowing Rehabilitation in Unilateral Hemispheric Stroke: A Scoping Review

Abstract

Background. Stroke is a significant health concern globally, and dysphagia has been a very common complication. Early intervention for managing dysphagia is challenging with a lack of universally accepted treatment protocols. Noninvasive repetitive transcranial magnetic stimulation (rTMS) is emerging as a treatment option for stroke dysphagia. However, there is no standardized rTMS treatment protocol for it, leading to challenges in clinical decision-making.

Objective. To determine available rTMS protocols for unilateral hemispheric stroke dysphagia.

Methods. A scoping review using PubMed, ProQuest, and EBSCOHost databases was conducted using the keywords “dysphagia,” “stroke,” “repetitive transcranial magnetic stimulation,” “conventional therapy,” and “swallowing examination.” Eligible studies published from inception to April 2020 were appraised using the Oxford Centre for Evidence-Based Medicine and analyzed qualitatively.

Results. Out of 42 articles, five randomized controlled trials met the eligibility criteria. A total of 108 patients with stroke and oropharyngeal dysphagia were randomized into one of the following treatment groups: (1) rTMS (unilateral or bilateral); (2) conventional dysphagia therapy (CDT); and (3) combined intervention (CI) of rTMS and CDT. The CI gave significant improvements in swallowing function and quality of life compared to CDT alone. The bilateral rTMS protocol resulted in more significant improvements than unilateral rTMS.

Conclusion. There are various and heterogeneous treatment protocols involving neuromodulation available for stroke dysphagia. The combination of bilateral excitatory-inhibitory rTMS and CDT seems to result in an optimal outcome for swallowing function among patients with unilateral hemispheric stroke dysphagia.