Anatomy, physiology and pathophysiology of dysphagia.

This is a review paper examining the pathogenesis of oropharyngeal dysphagia. Pharyngeal anatomy and physiology are discussed along with a detailed description of the neuronal architecture and function of the medullary swallowing center. The oropharyngeal swallow is then examined in biomechanical terms emphasizing that the swallow is comprised of several elements (velopharyngeal closure, upper esophageal sphincter opening, closure of the laryngeal vestibule, tongue loading, tongue pulsion and pharyngeal clearance) each of which can be compromised, causing dysphagia. The key modality for evaluating patients with oropharyngeal dysphagia is the videofluoroscopic swallowing study which is analyzed according to the efficacy with which these functional elements of the swallow are accomplished. Specific therapy can then be addressed toward correcting dysfunctional elements.