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Retropharyngeal edema, airway obstruction, and caval thrombosis.

A 3#{189}-month-old boy, previously healthy, was seen by his local physician with insidious onset of ‘ ‘crouplike’ ‘ symptoms. He had a thick neck, prominent scalp veins, an enlarging head, and bluish discoloration of the head, neck, and upper chest. In retrospect the mother believed that thickening of the neck was present as far back as age 7 weeks. Because of these findings, the patient was referred to our institution for further evaluation. A lateral view of the neck demonstrated diffuse retropharyngeal soft-tissue thickening and anterior displacement of the upper airway (fig. 1 ). Because a retropharyngeal tumor was suspected, CT was performed, but no tumor was defined; only diffuse soft-tissue thickening was present. Because of the distended veins, a radioisotope venogram using technetium-99m pertechnetate was performed. With injection into the left arm, there was normal venous flow to the chest wall; beyond this point, only collateral circulation was noted (fig. 2). There was no flow through the left innominate vein and superior vena cava. Subsequent arteriography revealed obstruction of the brachiocephalic veins on drainage films (fig. 3). The superior vena cava and innominate veins were not opacified. Since there were no compressive lesions, it was concluded that obstruction was secondary to thrombosis. Surgical exploration 8 days later demonstrated that no mass was present in the retropharyngeal space and that only edema was the problem. No further therapy was instituted and eventually retropharyngeal edema and respiratory distress disappeared.