The word dysphagia (swallowing disorder) is of Greek origin, with the prefix dys meaning difficulty and the stem phaiga meaning to eat. Dysphagia, or difficulty in swallowing, occurs early in stroke. Its incidence has been reported to be as high as 51%. In patients with brainstem stroke, the incidence is as high as 81%. Interventional treatment of swallowing disorders is part of the operational treatment of stroke. Anatomy and physiological mechanism of normal swallowing movement Swallowing movement is divided into five stages: 1. Pre-oral: In the pre-oral period, the patient perceives food through vision and smell, forms the desire to eat, prepares to eat, and delivers food to the mouth with utensils, cups or fingers. 2. Oral prep: Patients should open their mouth fully, accept the food mass and keep it in the mouth, perceive the food in the mouth, and taste the taste and texture of the food mass. In case of solid food, masticatory muscles, jaw and cheek movements, preparation of the food mass to make it suitable for swallowing are required. During this stage, the soft palate is located at the back of the tongue to stop the flow of food or fluids into the pharynx. 3. Oral phase: In the oral phase of swallowing, the prepared food mass is pushed toward the pharynx through the oral cavity. The lip and buccal muscles contract to deliver the food mass backward, while the tongue contacts the hard palate to push the food mass backward, driving the food mass through the oral cavity to the root of the tongue. 4. Pharyngeal phase: At this stage of swallowing, subsequent movements occur rapidly and sequentially, producing a swallowing reflex with the soft palate lifting up, closing the nasal cavity, closing the vocal cords, and closing the airway to prevent misaspiration and laryngeal penetration. The epididymis covers the laryngeal opening (laryngeal vestibule), which prevents the food mass from penetrating into the larynx and going directly into the pyriform fossa. The larynx moves upward and tilts forward, and pharyngeal peristalsis squeezes the food mass to move through the pharynx to the cricopharyngeal muscle. The cricopharyngeal muscle is located in the upper part of the esophagus, and when it is relaxed, the food mass can pass through and enter the esophagus. 5.The esophageal phase begins when the esophageal mass passes through the cricopharyngeal sphincter. The esophagus produces sequential peristaltic waves to push the food mass through the esophagus, and the lower esophageal sphincter, located at the lower end of the esophagus, then relaxes to allow the food mass to enter the stomach. Innervation of swallowing Cortical and subcortical centers control the autonomic part of swallowing movements (the part under conscious control), especially in the preoral, oral prep, and oral phases of swallowing. Swallowing movements can be initiated autonomously consciously or involuntarily reflexively. Swallowing movements are controlled by cerebral nerves whose nuclei are located in the medulla oblongata, and nerve afferents from the nuclei of the medulla oblongata come from the cortical, subcortical centers.