Paratracheal air cysts are uncommon findings in the pediatric population.

PURPOSE: To determine the prevalence of paratracheal air cysts (PACs) in the pediatric population.

METHODS

The chest CT images of pediatric patients between July 2007 and December 2014 were retrospectively reviewed for the presence and imaging findings of PACs. In addition, the association between PACs and the presence of bronchiectasis and air cystic pulmonary lesions were evaluated.

RESULTS

Among a total of 819 pediatric patients (males = 527, 64.3 %), the overall prevalence of PACs was 1.3 % (n = 11; 1.7 % for infants, 0.4 % for children, and 1.9 % for adolescents). The presence of PACs showed no association with gender, age groups, or the presence of bronchiectasis and air cystic pulmonary lesions (P = 0.56, 0.88, 0.57 and 0.89, respectively). All PACs were located at the right side of the trachea at the thoracic inlet, and the median transverse diameter was 3.7 mm (range 2.0-7.0 mm); one PAC showed septation, and 27.3 % of PACs had communication with the trachea.

CONCLUSION

In the pediatric population, the prevalence of PACs is 1.3 % as detected by chest CT. Knowledge of the prevalence and imaging findings of PAC would be useful to prevent confusion with pneumomediastinum or other cystic lesions in pediatric patients.