To comprehensively evaluate the efficacy of cerebellar transcranial magnetic stimulation in the rehabilitation of PSD.
A computer-based search was conducted across six Chinese and English databases, including CNKI (China National Knowledge Infrastructure), Wanfang Data, Web of Science, PubMed, Cochrane Library, and Embase. The search covered randomized controlled trials on the improvement of PSD by cerebellar TMS published up to February 2024. A comprehensive search strategy combining subject headings with free-text terms was employed, using keywords such as "stroke," "Cerebrovascular Accident," "Cerebrovascular Apoplexy," "Hemorrhagic Stroke," "Ischemic Stroke," "Transcranial Magnetic Stimulation," "TMS," "TBS," "stimulation," "Cerebellum," "cerebella," and "Parencephalon." The Penetration-Aspiration Scale (PAS) was used as primary outcome, while secondary outcomes included the Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS) and the amplitude of the pharyngeal motor-evoked potentials (PMEP). Effect sizes were pooled using RevMan 5.4. The quality and risk of bias of included studies were independently assessed using the PEDro scale and Cochrane Risk of Bias Assessment Tool 2.0 (RoB2). Subgroup analyses were performed for PAS based on stimulation sites and modes.
A total of 3059 articles were searched, of which 6 were ultimately included. Meta-analysis demonstrated that cerebellar transcranial magnetic stimulation significantly reduced the PAS scores [Fixed, MD=-0.85, 95%CI= -1.13 to -0.57, p0.00001] and the FEDSS scores [Fixed, MD=-0.50, 95%CI= -0.77 to -0.22, p=0.0004], while significantly increasing the amplitude of the PMEP [Fixed, MD=45.61, 95%CI= 9.04 to 82.19, p=0.01]. Subgroup analysis of PAS demonstrated that cerebellar TMS had significant effects compared to the control group, regardless of whether unilateral or bilateral stimulation was applied [unilateral cerebellar, Fixed, MD=-0.77, 95%CI= -1.09 to -0.44, p0.00001], [bilateral cerebellar, Fixed, MD=-1.09, 95%CI=-1.64 to -0.54, p0.0001]. Additionally, cerebellar TMS showed significant effects compared to the control group, regardless of whether traditional repetitive TMS (rTMS) or intermittent theta-burst stimulation (iTBS) was used [rTMS, Fixed, MD=-0.79, 95%CI= -1.19 to -0.39, p=0.0001], [iTBS, Fixed, MD=-0.91, 95%CI=-1.30 to -0.52, p0.00001].
Cerebellar TMS, serving as an adjunctive rehabilitation therapy for PSD, can ameliorate dysphagia by modulating the excitability of swallowing-related neurons in the cerebral cortex. However, further research with larger sample sizes and longer follow-up periods is needed to confirm these results and to explore the optimal TMS parameters for PSD.
Cerebellar TMS offers a novel, non-invasive treatment option for PSD, possessing potential for widespread application. This outcome will translate into a new therapy in physical therapy practice, where conventional swallowing training combined with cerebellar TMS will provide a more effective rehabilitation program for PSD.
dysphagia
transcranial magnetic stimulation
