<P> For barium meal or barium follow - through examinations, a 6 - hour period of fasting is observed prior to the studies . Barium is administered orally, sometimes mixed with diatrizoic acid to reduce transit time in the bowel . Metoclopramide is sometimes also added to the mixture to enhance gastric emptying . X-ray images are then taken in a supine position at intervals of 20--30 minutes . Real - time fluoroscopy is used to assess bowel motility . The radiologist may press or palpate the abdomen during images to separate intestinal loops . The total time necessary for the test depends on the speed of bowel motility or transit time and may vary between 1 and 3 hours . </P> <P> For small bowel examinations, in addition to fasting for 8 hours prior to examination, a laxative may also be necessary for bowel preparation and cleansing . Enteroclysis involves the continued infusion of 500 to 1000 mL of thin barium sulfate suspension into the intestine through a duodenal tube . Then methylcellulose is instilled through the tube . Barium and methylcellulose fill the intestinal loops which can be viewed continuously using fluoroscopy, or viewed as standard radiographs taken at frequent intervals . The technique is a double - contrast procedure that allows detailed imaging of the entire small intestine . However, the procedure may take 6 hours or longer to complete and is quite uncomfortable to undergo . </P> <Ul> <Li> Enteroclysis has shown to be very accurate in diagnosing small bowel diseases, with a sensitivity of 93.1% and specificity of 96.9% . It permits detection of lesion which may not be seen with other imaging techniques . There is no significant difference in terms of detection of clinically significant findings, sensitivity or specificity between enteroclysis and CT enterography . Enteroclysis compares favorably with wireless capsule endoscopy and double - balloon endoscopy in the diagnosis of mucosal abnormalities of the small bowel . </Li> <Li> The interpretation of standard barium swallow examinations for assessing dysphagia is operator and interpreter dependent . It has poor sensitivity for subtle abnormalities but is more sensitive in detecting esophageal webs and rings than gastroscopy . The best initial evaluation of suspected oropharyngeal dysphagia is a barium study . Barium swallow studies remain the main investigation of dysphagia . Barium studies may detect pharyngeal tumors that are difficult to visualize endoscopically . </Li> <Li> Barium follow through examinations are the most commonly used imaging technique in assessing patients with Crohn's disease, although CT and magnetic resonance imaging are widely accepted as being superior . However Barium examinations remain superior in the depiction of mucosal abnormalities . The features of Crohn's disease are well described by barium follow - through examinations, appearing as a typical "cobblestone pattern", but no information is obtained regarding extraluminal disease . Radiographic imaging in Crohn's disease provides clinicians with objective evaluations of small bowel regions that are not accessible to standard endoscopic techniques . Because of its length and complex loops, the small intestine is the most difficult part of the gastrointestinal tract to evaluate . Most endoscopic techniques are limited to the examination of proximal or distal segments, hence Barium follow through remains in most centres the test of choice for the investigation of abdominal pain, diarrhoea and in particular diseases manifesting mucosal abnormalities such as coeliac and Crohn's disease . </Li> <Li> Barium swallow studies are better than endoscopy at demonstrating the anatomic findings in gastroesophageal reflux disease after anti-reflux surgery . </Li> <Li> Barium fluoroscopic examinations have some advantages over computed tomography and magnetic resonance techniques, such as higher spatial resolution and the ability to examine bowel peristalsis and distension in real time . </Li> <Li> Many infections and parasitic infestations produce patterns of the luminal surface, which are best seen on Barium examinations . Certain parasites are seen as filling defects outlined by Barium and Barium examinations play an important role in the diagnosis of intestinal infections and infestations as compared to other techniques . Barium studies show tapeworms and roundworms as thin, linear filling defects of the bowel . Because roundworms have a developed alimentary tract, barium may outline the parasites' intestinal tracts on delayed images . In Strongyloidiasis barium studies show intestinal wall oedema, thickening of intestinal folds with flattening, and atrophy of the overlying mucosa . Schistosomiasis caused by infection with flatworms have an appearance resembling colitis ulcerosa, with inflammatory polyps, ulcers, fibrosis, wall thickening, loss of haustration, and stenosis in Barium X-rays . Anisakiasis is demonstrated by Barium X-rays as bowel wall oedema, thickening, ulceration, or stricture due to inflammation . Sometimes worms are seen as long, thread - like, linear filling defects up to 30 cm long . In Typhlitis Barium studies show oedema, ulceration, and inflammation of bowel wall resulting in wall thickening . In pseudomembranous colitis, barium studies show pancolitis with thumb printing and shaggy margins as well as plaque - like eccentric, nodular or polypoid appearance . </Li> <Li> Barium studies and computer tomography are the most common tools used to diagnose gastrointestinal lymphoma . Barium contrast is more sensitive in the demonstration of subtle mucosa and sub-mucosa abnormalities but computer tomography is the method of choice for determining the extent of disease and staging as well as related complications such as fistulation and perforation . Submucosal nodules or masses form a bull's - eye or target appearance on barium studies . </Li> </Ul> <Li> Enteroclysis has shown to be very accurate in diagnosing small bowel diseases, with a sensitivity of 93.1% and specificity of 96.9% . It permits detection of lesion which may not be seen with other imaging techniques . There is no significant difference in terms of detection of clinically significant findings, sensitivity or specificity between enteroclysis and CT enterography . Enteroclysis compares favorably with wireless capsule endoscopy and double - balloon endoscopy in the diagnosis of mucosal abnormalities of the small bowel . </Li>

An upper gi series is also referred to as a barium