Prenatal diagnosis of lobar bronchial atresia.

We report three cases of fetal lobar bronchial atresia referred to our Fetal Medicine Center during the mid-trimester of pregnancy over the last 15 years. Lobar bronchial atresia can mimic a main stem bronchial atresia on mid-trimester ultrasound examination as it induces extensive lobar enlargement, major mediastinal shift and eversion of the diaphragm. It was associated with severe pulmonary hypoplasia in all three cases, even though polyhydramnios and ascites were absent in two. Termination of pregnancy was performed at parental request after extensive counseling in each of the cases and necropsy confirmed one or two enlarged lung lobes leading to major compression of the remaining lobe(s) of the ipsilateral lung, the contralateral lung and the heart. No other anomalies were observed and the karyotype was normal in all cases.