Clinical study and mechanism of vagus nerve stimulation in the treatment of dysphagia after stroke

INTERVENTION: Vagus nerve stimulation group:Vagus nerve stimulation and Regular swallowing training;Neuromuscular electrical stimulation group:Neuromuscular electrical stimulation and Regular swallowing training;Control group:Regular swallowing training; CONDITION: Dysphagia after stroke PRIMARY OUTCOME: videofluoroscopic swallowing study; SECONDARY OUTCOME: Drinking water test in Watian;standardized swallowing assessment;Eating Disorders Quality of Life; INCLUSION CRITERIA: 1. For clinically confirmed ischemic stroke, refer to the 2018 version of the diagnostic criteria formulated by the Neurology Branch of the Chinese Medical Association and the Cerebrovascular Disease Group of the Neurology Branch of the Chinese Medical Association; Patients with hemorrhagic stroke should refer to the 2014 diagnostic criteria of the Chinese guidelines for the diagnosis and treatment of cerebral hemorrhage; 2. Ischemic stroke or hemorrhagic stroke confirmed by CT or MRI; 3. Age >= 18 years old; 4. Dysphagia confirmed by swallowing angiography, or meet the >= level 4 of the Watian drinking water test, or have a functional oral intake scale (FOIS) score <= 5 points; 5. Be willing and sign the informed consent form1. Discuss the evaluation of vagus nerve stimulation on the swallowing contrast score of patients with swallowing disorders after stroke, such as the standard swallowing function evaluation scale (SSA), the quality of life scale (ED