Congenital lobar emphysema mimicking cystic mass in a newborn.

Congenital lobar emphysema (CLE) is thought to be a result of obstruction of the bronchus which causes air-trapping and overinflation of lung segments or lobes. It usually presents as a hyperlucent region on chest radiography. However, if there is accompanying retention of lung fluid, the affected region becomes opaque. Of such a lesion, the computed tomography (CT) scans or ultrasonographic findings have been rarely mentioned in the literature. We report the CT and echographic findings of CLE with retained lung fluid in a newborn. The lesion presented as a cystic mass on CT; ultrasonographic examination demonstrated its real solid contexture.