When the esophagus stops working properly, people develop a condition known as dysphagia, or impaired swallowing. It is not a pleasant experience as it interferes with the person's ability to maintain a healthy diet. It sometimes causes pain as well. Doctors use several methods of swallow study for dysphagia in order to diagnose and treat this condition.

Swallowing is done by the tongue's action pushing the food into the throat. From there, the esophagus massages the food along its length through peristalsis, or the rhythmic contractions of the muscles in its walls. The process ends when the ingested matter is propelled into the stomach through the gastric sphincter.

There are several possible causes for the prevention or impairment of this process. Sometimes it might be due to the weakness or abnormal functioning of the muscles in the gullet walls. The muscles may also be strained or lacerated.

Diffuse spasms occur when the peristaltic action is unusual, presenting in rapid bursts of very strong contractions. This is not unlike a heart that is suffering arrhythmia. It is the involuntary esophageal muscles that cause this disorder.

Obstructions in the esophagus are another possible reason. Big pieces of food can get lodged there, and if a person has esophageal tumors they may have the same consequence. Blockages can potentially be the result of any foreign matter or debris.

On a broader level, neurological issues can also impair swallowing. People who have recently suffered a stroke or other injury to the nervous system can lose gullet function. Certain nervous disorders, such as polio or Parkinson's disease, may have the same effect.

Monitoring the swallowing action is necessary in diagnosing the problem. The person is asked to eat or drink something that has been infused with barium, which is the contrast material. The X-ray cannot show muscle tissue but in the presence of barium it is able to, because the metal reflects the X-rays. Their esophagus is then checked to see how it functions as it processes the ingested material. This is known as a dynamic swallowing exercise.

Secondly, a dynamic swallowing exercise is a live depiction of patient gullet action. The latter swallows barium food or liquid and is then monitored as it passes through to their stomach. The working of their food canal is assessed to see if it is healthy.

Endoscopy is a general term for the technique in medicine in which a camera-loaded cable is passed into the body through an orifice. This is a Greek term meaning inner vision. It allows the doctor to physically see the gullet's interior and make an assessment of its interior and muscles.

This process is made more advanced in a dynamic swallowing exercise, where the patient's swallowing action is monitored as it happens. This is also done by using barium as the contrast material. It provides a real-time display of what is happening in the food passage.

These techniques are not hard to undergo. It is typically older people who suffer from dysphagia, but if difficulty in eating or drinking continues for an inordinate period of time, it should be investigated.