Effects of rTMS Combined with Oral Stimulation on Oral and Pharyngeal Swallowing Function Based on Frequency Differences in Stroke Patients with Dysphagia

This study aimed to compare the effects of different frequencies of repetitive transcranial magnetic stimulation (rTMS) on swallowing muscle activity and function in poststroke dysphagia (PSD). Ten stroke patients were selected and divided into two groups: one received 5 Hz high-frequency rTMS with oral stimulation (HFrTMSO) targeting the lesioned hemisphere, whereas the other received 1 Hz low-frequency rTMS with oral stimulation (LF-rTMSO) targeting the non-lesioned hemisphere. The intervention was conducted three times a week for four weeks. Swallowing muscle activity was measured using maximal tongue strength and electromyography (EMG) of the suprahyoid muscle. Swallowing function was evaluated using videofluoroscopic swallowing studies and the functional dysphagia scale (FDS). Results showed the HF-rTMSO group had significantly better muscle activity during dry and rice swallowing compared to the LF-rTMSO group (p<0.05). Although there was no significant difference in overall FDS scores, the vallecula residue item notably improved in both groups. This suggests HF-rTMS is more effective than LF-rTMS in enhancing swallowing muscle activity and function in PSD.