Chest radiographs were ordered because of the diminished breath sounds, prolonged cough history, and the child's previous foreign object ingestion episode. The radiographs (Figures 1 and 2) were negative for a foreign object but demonstrated an abnormal soft tissue density posterior to and to the right of the trachea. This soft tissue density was causing a mass effect that displaced the trachea laterally to the left. The density could be seen on the lateral projection at the approximate level of the fourth thoracic vertebrae along the posterior margin of the trachea. The lungs were clear without pneumothorax, effusion, or focal consolidation, and her heart size was normal. The radiologist commented that the soft tissue density could represent a right aortic arch or other vascular anomaly, a soft tissue mass, or lymphadenopathy and recommended computed tomography (CT) of the child's chest.
A chest radiograph (lateral view) illustrates abnormal soft tissue density posterior to and to the right of the trachea, visible at the level of the fourth thoracic vertebrae and causing a mass effect that displaces the trachea laterally to the left. The arrow identifies the second arch that is displacing the trachea and esophagus.
A chest radiograph (posterior-anterior view) demonstrates abnormal soft tissue density (dashed arrow) displacing the narrowed trachea (solid arrow).
The following week, the child had a chest CT scan that demonstrated a double aortic arch (DAA) with a dominant right arch (Figures 3 and 4). The left subclavian and left common carotid arteries arose from the left arch, while the right subclavian and right common carotid arteries arose from the right arch. There were no additional vascular abnormalities. The radiologist stated that the DAA accounted for the paratracheal mass that had been seen on the chest radiograph.
A computed tomography scan without contrast demonstrates a vascular ring surrounding and compressing the trachea (arrow).
A computed tomography scan with contrast demonstrates tracheal compression (arrow). The esophagus is not visible because of compression by the vascular ring.
The child was referred to a pediatric cardiologist for evaluation and management. An echocardiogram confirmed the presence of a DAA. The right arch was larger than the left arch, but there was no coarctation of the right aortic arch, and corrective surgery was recommended to relieve the tracheal ring malacia.
J Pediatr Health Care. 2014;28(3):267-271. © 2014 Mosby, Inc.