Dysphagia After Stroke

Post-stroke dysphagia is a common complication that negatively affects nutritional status, quality of life, and morbidity. Conventional swallowing rehabilitation, including oropharyngeal exercises and neuromuscular electrical stimulation (NMES), is widely used to improve swallowing function. This randomized controlled clinical study aims to investigate the effectiveness of visual biofeedback-assisted oropharyngeal exercises combined with NMES in patients with post-stroke dysphagia. Participants will be randomly assigned to either a visual biofeedback-assisted exercise group or a conventional exercise group, with both groups receiving NMES. Treatment will be administered five days per week for four weeks. Changes in swallowing function, suprahyoid muscle activity assessed by surface electromyography, and muscle stiffness evaluated by shear wave elastography will be analyzed to determine the effectiveness of the intervention.

It is estimated that 400,000 to 800,000 people worldwide develop neurogenic dysphagia annually. Stroke represents the most common etiology, with approximately 65% of acute stroke patients experiencing pharyngeal swallowing difficulties. Clinical manifestations of dysphagia vary widely in severity and may include residue, reflux, delayed swallowing initiation, aspiration, and cricopharyngeal muscle dysfunction. Due to its detrimental effects on nutrition, respiration, and psychosocial well-being, dysphagia significantly impairs patients' quality of life. Furthermore, the inability to swallow safely and efficiently can lead to serious complications such as aspiration pneumonia, malnutrition, and depression. The traditional swallowing rehabilitation treatment has limited effect in clinical practice, which makes it necessary to search for new effective swallowing methods. Conventional swallowing rehabilitation often yields limited clinical benefits, highlighting the urgent need for more effective therapeutic strategies. Transcranial direct current stimulation (tDCS) is a non-invasive and safe neuromodulation technique that has shown promise in the field of neurorehabilitation. Its mechanisms extend beyond immediate cortical modulation and cerebral blood flow changes to include the regulation of synaptic plasticity, neurotransmitters such as glutamate and GABA, and excitability in remote subcortical regions. In recent years, tDCS has been increasingly applied to various neurological disorders, including post-stroke motor impairment, dysphagia, aphasia, depression, addiction, and spinal cord injury-related movement disorders. Currently, tDCS is being explored to elucidate its regulatory effects on cerebellar swallowing control, positioning it as a potential innovative treatment for neurogenic dysphagia.

The goal of this clinical trial is to investigate the effects of a combined swallowing intervention (Neuromuscular Electrical Stimulation (NMES) + Neuromuscular Taping (NMT) + swallowing exercises) on swallowing function and quality of life in post-stroke dysphagia patients. The main questions it aims to answer are: • Does the combination of swallowing exercises, NMES \& NMT have a greater improvement in dysphagia rehabilitation when compared to either NMES or NMT alone? Researchers will compare the effects of intervention between the three groups (NMES and swallowing exercises, NMT and swallowing exercises, and NMES with NMT and swallowing exercises). Participants will: * Receive a combined dysphagia rehabilitation comprised of swallowing exercises, Neuromuscular Electrical stimulation, and/or Neuromuscular Taping. * Visit the clinic once every 5 days a week for 10 therapy sessions. * Undergo baseline and post-intervention evaluation procedures.

Swallowing activity in the oral phase is regulated by the cortical swallowing network, and the functional connectivity pattern of the cortical swallowing network is related to swallowing activity. The structural damage of the cortical swallowing network and abnormal activation of brain areas related to swallowing in post-stroke dysphagia affect swallowing activity. The recovery of dysphagia after stroke is related to the compensation of swallowing network in the contralateral hemisphere and different connectivity patterns of diseased brain areas, and the integrity of cortical swallowing network connectivity affects the sequence of oral swallowing activities. However, it is not clear how the functional connectivity patterns and interactions of brain regions of the cortical swallowing network related to oral swallowing activity change in patients with oral dysphagia after stroke.