Barium swallow 2150307 208502776 2008-04-27T11:17:32Z 87.194.20.159 /* Principle */ A '''barium swallow''' is a [[medical imaging]] procedure used to examine the upper GI (gastrointestinal) tract, which includes the esophagus and, to a lesser extent, the stomach. [[Image:Barium swallow.gif|thumb|right|200px|A Barium Swallow image]] ==Principle== [[Barium sulfate]] is a type of [[contrast medium]] that is visible to x-rays. As the patient swallows the barium suspension, it coats the esphagus with a thin layer of the barium. This enables the hollow structure to be imaged. This is commonly used with [[baking soda]] ([[sodium bicarbonate]] crystals) to produce gas (''see [[Sodium bicarbonate#Chemistry|Reactions of sodium bicarbonate]]''). As gas is low in density, and the X-rays pass through very easily, they will appear as black patches, as opposed to the white produced by relatively-dense barium. As such, it is extremely useful in providing a contrast to the barium, to produce a double contrast image, to allow better visualisation of the contrasting features within the [[mucosal layer of the esophagus]]. Note, however, that this technique induces gas production in the esophagus, and will be uncomfortable to the subject. Barium sulfate is irritable outside the [[gastrointestinal tract]]. In cases where a leak is suspected or desired to be demonstrated, contrast imaging involving the use of [[water-soluble contrast media]] containing iodine is used. As with all X-rays, the barium swallow technique employs [[radiation]], and may irradiate the patient unnecessarily. The barium swallow should not be used unless required, and, although it cannot be replaced by [[endoscopy]] as for the [[barium enema]], should be avoided as much as possible for children and pregnant women. ==Examination== The patient is asked to drink a suspension of [[barium sulfate]]. [[Fluoroscopy]] images are taken as the barium is swallowed. This is typically at a rate of 2 or 3 frames pers second. The patient is asked to swallow the Barium a number of times, whilst standing in different positions, i.e. AP, oblique and lateral, to assess the 3D structure as best possible. ==Pathology== Pathologies detected on a Barium Swallow include: *[[Achalasia]] *[[Cancer of oesophagus]] *[[Tracheoesophageal fistula]] *[[Schatzki ring]] *[[Gastroesophageal reflux disease]] (GERD/GORD) *[[Zenker's diverticulum]] *[[Hiatus hernia]] *Obstruction of esophagus *Esophageal stenosis *Dementia ==See also== *[[Barium enema]] *[[Barium meal]] *[[Barium follow-through]] ==References== *Boon et al. Davidson's Principles & Practice of Medicine, 20th Edition, Chapter 22 *Harvard Health Publications - Diagnostic Tests - Barium Swallow - ''http://www.health.harvard.edu/diagnostic-tests/barium-swallow.htm'' *Medline Plus Medical Encyclopedia - ''http://www.nlm.nih.gov/medlineplus/ency/article/003816.htm'' [[Category:Medical imaging]] [[Category:Diagnostic gastroenterology]] [[Category:Radiology]] [[Category:Barium]]