Nil by mouth for 4 h before. Oral contrast is given to opacify the small bowel and stomach, to help differentiate it from pathological masses, which may be of similar attenuation and difficult to separate from bowel. A suggested mixture is 800 ml water mixed with 16 ml of either meglumine/sodium diatrizoate (gastrografin, urografin) or similar contrast, to make a 2% solution of contrast. To make the urografin palatable, orange or other fruit squash should be added to taste. A dilute proprietary barium solution (EZ-CAT) can be uséd instead, made up as directed. A cup of the contrast is kept aside and the remainder is given to the patient 30–40 min prior to the scan. The final cup is taken immediately before the scan. This should ensure that the stomach and proximal small bowel are filled.
KeywordsLymphoma Attenuation Respiration Barium Teratoma
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