In most cases, the cause is
Progression of an injury to the esophagus
Food and foreign bodies
Injuries that can progress to obstruction can result from damage to the esophagus caused by the repeated backflow of acid from the stomach (gastroesophageal reflux or GERD), usually over years. Obstruction can also be caused by damage to the esophagus that occurs after swallowing a corrosive substance (erosive esophagitis) or rarely after inflammation of the esophagus caused by a pill that gets stuck in the esophagus for a period of time.
Narrowing may also occur when something presses against (compresses) the outside of the esophagus. Compression can result from a number of causes, such as
Because all these conditions decrease the diameter of the esophagus, people who have one of them usually have difficulty swallowing solid foods, particularly meat and bread. Difficulty in swallowing liquids develops much later, if at all.
To diagnose a blockage in the esophagus, doctors do an upper endoscopy. In this procedure, doctors examine the esophagus using a flexible tube called an endoscope. During the endoscopy, doctors take tissue samples to analyze under a microscope (called a biopsy).
Doctors may also do a barium swallow. In this test, people are given barium in a liquid before x-rays are taken. The barium outlines the esophagus, making abnormalities easier to see.
Treatment and outcome depend on the cause of the narrowing or blockage.