Radiologic features of inferior pulmonary ligament air collections in neonates with respiratory distress.

Radiologically characteristic extra-alveolar air collections in one or both inferior pulmonary ligaments developed in 14 neonates with respiratory distress on assisted ventilation. Eleven infants had radiographically visible pulmonary interstitial emphysema prior to or concurrent with the air collections. All infants subsequently exhibited pneumothorax. This variant of extra-alveolar air must be recognized because it has essentially the same pathogenesis and significance as the more commonly seen anterior pneumomediastinum.