20. Pharynx, barium swallow, lateral projection
The patient has been imaged during deglutition (swallowing). The nasopharynx
lies above the soft palate and behind the nasal cavities. The oropharynx
lies behind the oral cavity. Radiopaque barium is located in the valleculae,
the paired (and on this projection, superimposed) spaces between the posterior
surface of the tongue and the epiglottic shadow. The laryngopharynx lies
behind the opening into the larynx. The piriform recesses (or fossae),
depressions in the mucous membrane on either side of the laryngeal inlet, also
contain barium. Just distal to the proximal esophageal sphincter the esophageal
lumen contains air and a light coating of barium on the mucosal surface (see
Image #21).
