1Gastroesophageal reflux scanDefinitionGastrointestinal reflux imaging refers to several methods of diagnostic imaging used to visualize and diagnose gastroesophageal reflux disease (GERD). GERD is one of the most common gastrointestinal problems among children or adults. It is defined as the movement of solid or liquid contents from the stomach backward into the esophagus.PurposeThe purpose of gastroesophageal reflux scanning is to allow the doctor to visualize the interior of the patients upper stomach and lower esophagus. This type of visual inspection helps the doctor make an accurate diagnosis and plan appropriate treatment.DescriptionA brief description of gastroesophageal reflux disease is helpful in understanding the scanning methods used to diagnose it. Gastroesophageal reflux disease is the term used to describe the symptoms and damage caused by the backflow (reflux) of the contents of the stomach into the esophagus. The contents of the human stomach are usually acidic. Because of their acidity, they have the potential to cause chemical burns in such unprotected tissues as the lining of the esophagus.Gastrointestinal reflux is common in the general American population. Approximately one adult in three reports experiencing some occasional reflux, commonly referred to as heartburn. About 10% of these persons experience reflux on a daily basis. Most persons, however, have only very mild symptoms. Occasionally, someone may experience a burning sensation as a result of gastrointestinal reflux. This symptom is described as reflux esophagitis when it occurs in association with inflammation.Gastroesophageal reflux has several possible causes: An incompetent lower esophageal sphincter. Acid reflux can occur when the ring of muscular tissue at the boundary of the esophagus and stomach is weak and relaxes too far. Sphincter incompetence is the most common cause of gastroesophageal reflux. The acid juices from the stomach are most likely to flow backward through a weak sphincter when a person bends, lifts a weight, or strains. People with esophageal strictures or Barretts esophagus are more likely to experience gastroesophageal reflux than are others. Acid irritation. Gastric contents are acidic, with a pH lower than 3.9. This degree of acidity is very caustic to the lining of the esophagus; repeated exposures may lead to scarring. If the exposure is sufficiently severe or prolonged, strictures can develop. Occasionally, pancreatic enzymes or bile may also flow backward into the stomach and lower esophagus. These fluids are extremely acidic, with a pH lower than 2.0. Abnormal esophageal clearance. Clearance refers to the process of removing a substance from a part of the body, in this case the removal of stomach acid from the esophagus. Acid reflux is ordinarily washed out of the esophagus by the saliva that a person swallows over the course of a day. Saliva also contains some bicarbonate, which helps to neutralize the acidity of the stomach juices. During sleep, however, people swallow less frequently, which results in a longer period of contact between the 2acid contents of the stomach and the tissues that line the esophagus. The net result is a chemical injury. Sjgrens syndrome, radiation to the oral cavity, and some medications (anticholinergics) also decrease the flow of saliva and can result in chemical injury. Such other medical conditions as Raynauds disease and scleroderma are often associated with abnormal esophageal clearance. Hiatal hernia is present in more than 90% of persons with erosive disease. Delayed gastric emptying. When outflow from the stomach is blocked or the stomachs contractions are weakened, the partially digested food does not leave the stomach in a timely manner. This delay makes gastric reflux more likely to occur. Heartburn associated with gastroesophageal reflux occurs 3060 minutes after eating. It also occurs when a person is lying down. Most people who experience gastroesophageal reflux can obtain relief from heartburn with baking soda, bismuth subsalicylate (Pepto-Bismol), or antacid tablets. A pattern of symptom relief following a dose of one of these nonprescription remedies is usually enough to make the diagnosis of gastroesophageal reflux. Under these conditions, the results of a physical examination and laboratory tests are usually within normal limits.Persons with complicated GERD, or those who do not respond to nonprescription heartburn remedies, require special examinations. There are several imaging methods used in the diagnosis of GERD:Upper endoscopyUpper endoscopy is the standard procedure for diagnosing GERD, determining the degree of tissue damage, and documenting the findings. A barium esophagography may be performed in addition to an upper endoscopy. Between 50% and 75% of all patients diagnosed with GERD will have abnormalities in the mucous lining of the esophagus, usually erosion, tissue fragility, and erythema. Upper endoscopy is also