Current imaging of prenatally diagnosed congenital lung lesions

Abstract

Congenital lung lesions refer to a spectrum of pulmonary developmental anomalies including, but not limited to, bronchial atresia, congenital pulmonary airway malformation (formerly known as congenital cystic adenomatoid malformation) and bronchopulmonary sequestration. These anomalies comprise about 90% of the anomalies seen in clinical practice. The advent of prenatal sonography and, more recently, fetal magnetic resonance imaging has changed our understanding and practice in the evaluation of congenital lung lesions. Postnatal imaging using low-dose computed tomography angiography (CTA) is extremely useful as it may provide information essential for differential diagnosis by allowing multiplanar reconstructions of the airway, lung parenchyma, and vasculature. The use of iodine in CTA permits the application of low-dose radiation protocols in these young patients. The purpose of this article is to emphasize the technical factors that may optimize low-dose CTA evaluation of these lesions. We also provide a description of prenatal imaging findings and helpful diagnostic clues that may be useful for the characterization of the most commonly encountered prenatally diagnosed pulmonary developmental anomalies.