Left pulmonary artery sling presenting as unilateral echogenic lung on 20-week detailed antenatal ultrasound examination

Background We report the first case of left pulmonary artery sling (LPAS) presenting as unilateral echogenic lung at a routine 20-week antenatal US examination. The infant had minimal symptoms at delivery, but developed an oxygen requirement and respiratory distress from day 10 of postnatal life. Antenatal US and antenatal MRI indicated an intrathoracic anomaly, so permitting definitive investigations in the neonatal period using CT, MRI and helical-CT-acquired virtual bronchoscopy. The infant successfully underwent corrective surgery.