A newborn develops cyanosis and respiratory distress when quiet, which resolves dramatically during crying. Attempts to pass a fine catheter through both nostrils fail. Which investigation will BEST demonstrate the suspected anomaly?

• A Flexible fibreoptic laryngoscopy
• B Lateral soft tissue radiograph of the neck
• C Axial non-contrast CT of the nasal cavity with thin sections ✓
• D MRI brain with gadolinium

Explanation

The cycle of distress relieved by crying is classical for bilateral choanal atresia, because the crying infant breathes orally while the mouth is open. Failure to pass a catheter supports the diagnosis. Thin-section axial CT after suctioning the nose demonstrates the atretic plate, whether bony or membranous, and is the definitive imaging study. Laryngoscopy examines the larynx distal to the obstruction, plain radiographs do not resolve the posterior choanae, and MRI is reserved for associated intracranial anomalies.

Reference: Scott-Brown's Otorhinolaryngology Head and Neck Surgery, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.