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 (Ba) [bar´e-um]
a chemical element, atomic number 56, atomic weight 137.34. (See Appendix 6.) Ingestion of excessive amounts can be toxic, occasionally resulting in fatal hypokalemia and paralysis.
barium sulfate a water-insoluble salt used as an opaque contrast medium for x-ray examination of the digestive tract.
barium test x-ray examination using a barium mixture to help locate disorders in the esophagus, stomach, duodenum, and small and large intestines. Such conditions as peptic ulcer, benign or malignant tumors, colitis, or enlargement of organs that might be causing pressure on the stomach may be readily identified with the use of barium tests. If perforation exists or is suspected, the barium test should not be administered. It is important to evacuate the barium completely following the study; a mild laxative is usually prescribed for this purpose.

Barium sulfate is a harmless chalky, water-insoluble compound that does not permit x-rays to pass through it. Taken before or during an examination, it causes the intestinal tract to stand out in silhouette when viewed through a fluoroscope or seen on an x-ray film.

Two main types of tests are conducted with the use of barium: the barium meal or barium swallow, for radiologic examination of the upper gastrointestinal tract, and the barium enema for examination of the lower gastrointestinal tract.
Barium test: Barium meal and follow-through. Normal stomach and small bowel. From Aspinall and Taylor-Robinson, 2001.

bar·i·um (Ba),

(ba'rē-ŭm, bā'rē-ŭm),
A metallic, alkaline, divalent earth element; atomic no. 56, atomic wt. 137.327. Its insoluble salts are often used in radiology as contrast media.
[G. barys, heavy]


/bar·ium/ (Ba) (bar´e-um) a chemical element, at. no. 56. Its acid-soluble salts are poisonous; causing gastrointestinal symptoms followed by severe, sometimes fatal hypokalemia with paralysis.
barium sulfate  a water-insoluble salt, BaSO4, used as an opaque contrast medium in radiography of the digestive tract.


(bâr′ē-əm, băr′-)
1. Symbol Ba A soft, silvery-white or yellowish-white alkaline-earth metal, used to deoxidize copper and to absorb trace gases in vacuum tubes, and used in various alloys. Atomic number 56; atomic weight 137.33; melting point 727°C; boiling point 1,897°C; specific gravity 3.62; valence 2. See Periodic Table.
2. A radiopaque solution containing barium sulfate that is used to visualize the gastrointestinal tract on x-rays.

bar′ic (-ĭk) adj.

barium (Ba)

Etymology: Gk, barys, heavy
a pale yellow, metallic element classified with the alkaline earths. Its atomic number is 56; its atomic mass is 137.36. The acid-soluble salts of barium are poisonous. Barium carbonate, formerly used in medicine, is now used to prepare the cardiac stimulant barium chloride; fine, milky barium sulfate is used as a contrast medium in radiographic imaging of the digestive tract.


A silver-white alkaline earth-metallic element—atomic number 56, atomic weight 137.3—which melts at 727ºC. Pure barium does not exist in nature as it is oxidised, often as baryta.

Barium is the core constituent in non-radioactive radiocontrast studies (e.g., barium enema, barium swallow), and formulated as a chalky liquid, popularly, a milkshake.


(Ba) (bar'ē-ŭm)
A metallic, alkaline, divalent earth element; atomic no. 56, atomic wt. 137.327. Salts are often used in diagnostic x-rays.
[G. barys, heavy]


A chemical used in certain radiological studies to enhance visualization of anatomical structures.
Mentioned in: Intussusception


A metallic, alkaline, divalent earth element. Its insoluble salts are often used in radiology.
[G. barys, heavy]

barium (Ba) (ber´ēəm),

n a pale yellow, metallic element classified with the alkaline earths.
barium sulfate,
n a white, finely ground, tasteless powder that is insoluble in water, solvents, and solutions of acids and alkalis; used in radiography as a contrast medium because of its opacity to roentgen rays and as a protective barrier in plaster walls.


a chemical element, atomic number 56, atomic weight 137.34, symbol Ba. See Table 6. Soluble salts, e.g. the chloride and the carbonate, are toxic.

barium burger, barium meal
a mixture of barium and solid food, used as a contrast medium in radiographic studies of the esophagus, instead of liquid barium mixtures.
barium chloride
used as a rodenticide. The baits are attractive to dogs. Clinical signs include salivation, convulsions and paralysis.
barium deficiency
preliminary experiments showing that diets deficient in barium fed to rats and guinea pigs depress growth have been neither invalidated nor confirmed.
barium enema
a dilute (5 to 20%) suspension of barium is introduced into a colon that has been emptied by starvation and previous enema.
Enlarge picture
Barium enema. By permission from Ettinger SJ, Feldman E, Textbook of Veterinary Internal Medicine, Saunders, 2004
barium-impregnated polyethylene spheres (BIPS)
radio-opaque markers used to demonstrate intestinal obstruction and motility disorders; the spheres are given orally and their movement can be tracked radiographically.
barium meal
a strong (usually 100%) suspension of barium sulfate is administered to an animal which has been starved for at least 12 hours.
barium study
x-ray examination using a barium mixture to help locate disorders in the esophagus, stomach, duodenum, and the small and large intestines. Called also barium test.
barium sulfate
a water-insoluble salt used as an opaque contrast medium for x-ray examination of the digestive tract.
barium swallow
a small amount of barium paste or liquid administered orally and observed radiographically or by fluoroscopy for examination of swallowing and esophageal function.
barium test
barium study.
References in periodicals archive ?
The last chapter analyses barium petroleum sulfonate downstream markets.
Barium studies are often used to evaluate disordered swallowing, despite the risk of aspiration.
Postswallow barium residue was judged using a 3-point scale (0 = no residue, 1 = coating of residue, 2 = pooling of residue) for each swallow at four locations (oral cavity, valleculae, posterior pharyngeal wall, and upper esophageal sphincter).
5-mm BIPS by gavage into the crop by 1 of the following methods: 1) suspended in 10 mL of a mixture of 30 mL water with 1 g of a psyllium-based fiber supplement (Metamucil, Proctor & Gamble, Cincinnati, OH, USA), 2) 10 mL of a water-based lubricant (K-Y Jelly, Johnson and Johnson Health Care Systems Inc, Piscataway, N J, USA), 3) 10 mL of a water and ground commercial poultry food suspension (1 g of food in 30 mL water), 4) 10 mL of 30% barium sulfate suspension, or 5) administered concurrently with commercial whole bird seed as fed.
Laboratory determinations of barium were performed by atomic absorption spectroscopy (Perkin-Elmer model 5000) in the laboratory of the Estonian Environmental Protection Agency.
4 shows the potassium chloride (A) and barium chloride induced (B) contraction curve of guinea-pig ileum in the absence and presence of Plantago extract.
Liquid barium alone reproduced symptoms in only 3 of the 29 patients; after the addition of food provocation, 2 of those 3 patients had worsening symptoms.
In patients with secondary achalasia, barium studies usually reveal absent primary peristalsis in the body of the esophagus with tapered, beaklike narrowing of the distal esophagus near the gastroesophageal junction, mimicking the appearance of primary achalasia (Figure 5).
Numerous attempts to improve operation of the considered cathodes by alloying zirconium or hafnium with elements of IIA sub-group of the periodic table were not crowned with success [12], because compact zirconium, as other reactive metals, is produced in vacuum-arc furnaces, and during melting of zirconium, barium, strontium and calcium, which have high vapor pressure, never preserve in it in any noticeable amounts.
Everybody knows that you have to have either a complete colonoscopy or barium enema to exclude the disease.
In 2001, Fujifilm engineers took the lead to introduce Nanocubic technology, an entirely new coating technology utilizing both metal and barium ferrite particles to make magnetic recording layers 10X thinner than the super-high resolution of metal particle technology.
Kabushiki Kaisha Topcon, Tokyo, Japan, has been granted a patent for a white standard paint that is comprised of barium sulfate, a binder and a solvent.