Posterior pharyngeal tension pneumatocele.

This unusual clinical entity is presented as a rare variant of the more common posterior pharyngeal abscess. The more important considerations discussed are: (a) the necessity for routine chest radiography in a case of "croup", including a view of the laryngeal area to rule out a foreign body; (b) the importance of routine and regular follow-up after removal of a laryngeal or esophageal foreign body, including close consultation with the radiology department; and (c) the inherent life-threatening nature of the condition and the possible need for surgical intervention on an emergency basis.