Imaging description

A 16-month-old male infant presented with persistent symptoms of croup, unresponsive to treatment. Frontal and lateral chest radiographs (Fig. 15.1a, b) demonstrated widening of the superior mediastinum with marked attenuation of the lower extrathoracic and intrathoracic airway, displaced rightward and anteriorly. A mediastinal mass was suspected, therefore a contrast-enhanced chest CT scan was ordered. The anesthesiologist was extremely reluctant to give this child any sedation or anesthesia for CT; the risk was considered to be very high because of his compressed airway. Therefore the CT scan was obtained with the child fed, swaddled, and breathing quietly.

The CT examination (Fig. 15.1c–e) demonstrated smooth diffuse low-density tissue in the mediastinum, more suggestive of edema or infiltration rather than a focal mass or confluent adenopathy. No focal fluid or abscess collection was present. There was marked tracheal narrowing and displacement. In addition there was a thin linear density on the axial image (Fig. 15.1c) that appeared rounded on the coronal image (Fig. 15.1e, arrow) behind and to the left of the trachea; several central small rounded well-defined lucencies appeared to be part of this structure. This density did not correspond to any anatomic landmark but was located in the area of the esophagus. The overall appearance led to the suggestion by the radiologist that there was likely a chronically impacted esophageal foreign body with surrounding mediastinal inflammation, probably resulting from penetration or perforation of the esophagus. At a subsequent endoscopy an upper esophageal foreign body was found to be embedded in the esophageal wall with marked surrounding inflammation and granulation tissue. This was removed endoscopically with great difficulty. The object removed proved to be a plastic clamp from a mylar balloon. The child did well post operatively on antibiotic treatment with rapid improvement of respiratory symptoms.