In a definition essay, you explain the meaning of a certain term by giving a detailed description of it, and support your definition with clear examples or facts. Such explanations are needed if a term is special, abstract, disputed or does not have a common meaning.
Dysphagia may be caused by traumatic injuries to the head, neck, or chest and result from accidents or iatrogenic causes. In the latter category, both planned and inadvertent injuries to cranial nerves are common. Many accident victims have involvement of multiple sites.
Esophageal dysphagia is caused by disordered peristaltic motility or conditions that obstruct the flow of a food bolus through the esophagus into the stomach. Achalasia and scleroderma are the leading motility disorders, while carcinomas, strictures and Schatzki's rings are the most common obstructive lesions.