Figure 11b. Retropharyngeal abscess with mediastinal extension in a 2-year-old girl with pharyngeal perforation caused by a pen. (a) Axial CT scan shows extraluminal air and oral contrast material in the retropharyngeal space (arrow). (b) Axial CT scan obtained at a lower level than a shows mediastinal extension (arrows). (Figs 11a and 11b reprinted, with permission, from reference 10.)