102-4).ДЄ modified barium swallow evaluates the coordination of the swallow reflex. After the administration of thick barium suspension, phonation and a modified Valsalva maneuver are used to distend the pharynx (Fig. However, in some cases, such as tumors arising in the hypopharynx, air-contrast images are of use. 5 If the patient is unable to undergo the air-contrast portion of the thoracic esophagram, prone full-column imaging should be obtained in two orthogonal planes as an alternative.ДЄir-contrast images of the pharynx are not always necessary because this region is amenable to direct inspection. This provides exquisite mucosal detail and is most useful for the evaluation of small plaquelike mucosal tumors and the mucosal irregularities of esophagitis. The barium coats the mucosal surface, whereas the gas from the effervescent agent distends the lumen. An effervescent agent is first administered, followed by a thick barium suspension. 102-3) are obtained with the patient upright and in slightly left anterior obliquity. C, Normal air-contrast upright oblique image of the distal esophagus.ДЄir-contrast images of the esophagus (see Fig. An air bubble (arrow) can be distinguished from a true lesion because the air bubble moves during the examination. Contrast spills past the gastroesophageal junction (j) into the air-filled stomach. B, Full-column prone oblique image of the distal esophagus. A, Full-column prone oblique image of the upper thoracic esophagus.

Small mucosal lesions can sometimes be distinguished, but conventional tomography has been replaced almost universally by computed tomography (CT).ДЇigure 102-3. Linear and complex-motion tomography improve on conventional radiographs by blurring the soft tissues that obscure the pharyngeal walls. 3 However, xeroradiography had a narrow range of applications, and it is no longer available at most institutions. Xeroradiography is a historical technique that clearly delineated the soft tissues of the neck. One advantage of these techniques is the ability to emphasize subtle soft tissue differences, even in suboptimally exposed images. Instead of exposing a piece of film, the technologist captures an image on a reusable array of digital elements and reads the image directly into a computer. The laryngeal ventricle is barely visible as a dark wedge (arrow).Д¬hest radiographs occasionally reveal advanced esophageal abnormalities or pneumomediastinum, but fluoroscopy and cross-sectional imaging are preferred for evaluation of the thoracic esophagus.Д¬omputed radiography and digital radiography are the modern counterparts to screen-film techniques. The soft palate (s), tongue base (b), hyoid bone (h), and epiglottis (arrowheads) are marked. Lateral radiograph of the neck emphasizing soft tissues.

Another word for diagnostic imaging