CT findings of congenital neonatal pyriform aperture stenosis.

Congenital neonatal pyriform aperture stenosis (CNPAS) is a rare but potentially lethal condition that causes respiratory distress. The characteristic narrowing of the pyriform aperture along with other associated craniofacial dysmorphism is diagnosed using cross-sectional imaging such as computed tomography (CT) and magnetic resonance imaging. CT scan is the imaging of choice for confirming and characterizing CNPAS. Infants are obligate nasal breathers in the first 5 months of life. Hence, a high degree of clinical suspicion, prompt imaging diagnosis and adequate respiratory support is critical to help reduce the morbidity of this condition.