title: Two lesser known but useful signs of neonatal pneumothorax.
abstract: Two lesser known signs of neonatal pneumothorax are presented: the "large, hyperlucent hemithorax" sign and the "medial stripe" sign. In a review of 113 consecutive cases of proven neonatal pneumothorax, the large, hyperlucent hemithorax was the presenting sign in 29 and the medial stripe in 12 (25% and 11%, respectively). A left-sided preponderance of both signs but especially of the large, hyperlucent hemithorax remained unexplained. The practical significance of the signs, differential diagnosis, and influence of the Mach effect are described.
mesh_terms: D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000000981:diagnostic imaging*; D011030:Pneumothorax / Q000000981:diagnostic imaging*; D011859:Radiography