Paratracheal air cysts are uncommon findings in the pediatric population.
OBJECTIVE
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.


CONCLUSIONS
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.
Department of Radiology, Gachon University Gil Hospital, #1198, Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea.
Min Kyung
MK
Lee
Department of Radiology, Gachon University Gil Hospital, #1198, Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea. oneshot0229@gmail.com.
Eun Young
EY
Kim
Department of Radiology, Gachon University Gil Hospital, #1198, Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea.
Yu Mi
YM
Jeong
Department of Radiology, Gachon University Gil Hospital, #1198, Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea.
Jeong Ho
JH
Kim
Department of Radiology, Gachon University Gil Hospital, #1198, Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea.
Hye-Young
HY
Choi
D000293:Adolescent; D017677:Age Distribution; D000388:Air; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008476:Mediastinal Cyst / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015995:Prevalence; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed
Multidetector computed tomography; Paratracheal air cyst; Pneumomediastinum; Tracheal diverticulum