Effect Of Unilateral High Frequency Repetitive Transcranial Magnetic Stimulation On Swallowing Function And FMRI In Stroke Patients

Objective To observe the effects of unilateral repetitive transcranial magnetic stimulation(TMS)on swallowing function and functional magnetic resonance imaging(FMRI)in patients with dysphagia after stroke.Methods Thirty patients with dysphagia after stroke were divided into healthy side group(n=10),affected side group(n=10)and control group(n=10)according to random number table.All three groups received traditional rehabilitation swallowing training.On the basis of this,high-frequency rTMS was used to stimulate the corresponding cortical areas of the suprahyoid muscle group in the healthy side of the brain hemisphere at a frequency of 5Hz,with a stimulation intensity of 80%RMT,with a stimulation time of 2s and an interval of 10s for 20min in the affected group.High-frequency rTMS was used to stimulate the cortical areas of suprahyoid muscle group in the affected cerebral hemisphere at a frequency of 5Hz,with a stimulation intensity of 80%RMT,for 2s and 10s intervals for 20min.The control group was given shame rTMS on the basis of traditional rehabilitation swallowing training.The operation method,stimulation parameters and treatment course were the same as those of the first two groups,but only the probe was perpendicular to the patient’s skull without any stimulation.The efficacy was evaluated by swallowing functional communication measure swallowing(FCM)and modified Mann assessment of swallowing ability(MMASA)before treatment and 2 weeks after treatment.fMRI was also used to observe the changes of related brain regions in the three groups by the amplitude of low-frequency fluctuations(ALFF).Results After treatment,FCM score and MMASA score in the 3 groups were better than those before treatment(P<0.05),FCM score and MMASA score in the healthy group were(6.10±0.74)and(90.30±6.34),respectively.The FCM score and MMASA score of the affected group were(5.70±0.67)and(87.20±5.61)respectively,which were better than those of the control group(4.10±0.74)and MMASA score(81.60±6.75)(P<0.05).The difference values of FCM and MMASA before and after treatment in the healthy group were(3.90±0.99)points and(18.80±6.39)points,respectively,in the affected group were(3.40±0.97)points and(16.10±4.68)points,respectively.The difference of FCM and MMASA before and after treatment was(1.70±0.68)points and(9.20±8.16)points.There was no statistical significance in FCM score after treatment,MMASA score after treatment,difference of FCM before and after treatment and difference of MMASA before and after treatment between the healthy group and the affected group(P>0.05).After treatment,the ALFF in both the healthy and affected groups increased to varying degrees compared with the sham stimulation group(P<0.001),and the scattered ALFF in the healthy group was relatively more than that in the affected group(P<0.001).Conclusion 5Hz high-frequency rTMS applied to the cortical regions corresponding to the suprahyoid muscle group in both the healthy and affected hemispheres can improve dysphagia in stroke patients,and can promote the activation of ALFF related to dysphagia in stroke patients.High frequency rTMS in the healthy hemisphere can improve the excitability of the swallowing region of the brain more easily than in the affected hemisphere in some cases.