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April 17, 2002 -- This article is one in a series of white papers on patient positioning techniques. Appearing monthly on AuntMinnie.com, the articles will explore each of the major modalities. If you'd like to comment on or contribute to this series, please e-mail . The upper gastrointestinal (UGI) procedure includes radiographic and fluoroscopic evaluation of the esophagus, stomach, and duodenum while the patient is drinking a barium solution. Barium is completely inert, not absorbed, and not allergenic. The liquid barium has a chalky taste, although the taste can be masked somewhat by added flavors such as strawberry or chocolate. Spot films are obtained in various projections during the dynamic portion of the study. Subsequent to this, routine overhead films are obtained. Three approaches are commonly used.
Single-contrast upper gastrointestinal series In a single-contrast UGI examination, the outline of the barium-filled viscous provides the most apparent information, enabling any lesions causing contour defects such as large tumors and ulcers to be easily seen. However, small lesions such as small ulcers and polyps require fluoroscopically guided compression. Compression is critically important in the detection of these small lesions. The single-contrast UGI series uses a medium-density barium suspension that permits a combination of meaningful compression filming. Kilovoltage for most single-contrast studies should be in the range of 90-110 kVp to allow adequate penetration.
After the fluoroscopy and spot film are complete, the technologist obtains bucky films of the patient's stomach and duodenum using an overhead tube. The following views constitute a suitable set of bucky films:
Indications
If perforation is suspected, water-soluble contrast is used by convention.
Patient preparation The patient should be NPO (nothing by mouth) after midnight or for 6 hours prior to the exam. Supplies
Patient positioning and imaging techniques
Single-contrast upper gastrointestinal series with small bowel follow-through Indications
If perforation is suspected, water-soluble contrast is used by convention. Patient preparation NPO after midnight or 6 hours prior to exam. Supplies
Double-contrast GI series The double-contrast examination is a general study of the upper gastrointestinal tract from the pharynx to the duodeno-jejunal flexure that employs coating the mucosa uniformly with barium. A relatively small quantity of high-density barium (200-250% w/v) is used to demonstrate fine mucosal detail, and distension and double contrast are achieved by means of a gas-producing agent.
Biphasic upper gastrointestinal series The biphasic examination is a commonly used modification of the double-contrast technique whereby an additional quantity of dilute barium is given toward the end of an examination and further films are obtained of the compressible parts of stomach and duodenum. The goal of the biphasic examination is to have both mucosal delineation in the double-contrast phase and full column distension in the single-contrast phase. The advantage of this method is that it images some lesions better than by double contrast alone. After the radiologist completes the fluoroscopic and spot filming portion of the examination the technologist usually obtains two overhead radiographs. Both of these are obtained at 120 kVp.
Indications Mucosal disease (early erosions, ulcerations, polyps, cancer) Contraindications
NPO after midnight or 6 hours prior to exam.
Supplies
Patient positioning and imaging technique
AuntMinnie.com contributing writer April 17, 2002 Related Reading Positioning techniques for quality esophagrams, March 20, 2002 Dorsal and lateral decubitus patient positioning for abdominal x-ray exams, February 28, 2002 AP abdominal projection x-ray positioning techniques, January 16, 2002 Tips and techniques for decubitus and oblique chest x-rays, December 21, 2001 Mastering AP and lateral positioning for chest x-ray, November 20, 2001 Copyright © 2002 AuntMinnie.com What position will best demonstrate the pyloric canal and duodenal bulb in hypersthenic patients?The right lateral projec- tion commonly affords the best image of the pyloric canal and the duodenal bulb in patients with a hypersthenic habitus.
Which projection will demonstrate the duodenal bulb and loop in profile?positioning UGI. What is the best position to demonstrate duodenal loop?Duodenal loop: The patient lies prone on the compression pad to prevent barium flooding into the duodenum (additional views of the anterior wall of the duodenal loop can be taken in the right anterior oblique position).
What position will demonstrate the pylorus filled with barium and fundus with air?The LPO position (recumbent) produces an image in which the fundus and the body are filled with barium but the duodenal bulb is filled with air.
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