Mirrored Ribs: A Sign for Pneumothorax in Neonates*

OBJECTIVES: To evaluate if "mirrored ribs"-a mirroring of chest structures-is a sign for pneumothorax in lung ultrasound in neonates. DESIGN: Retrospective study. SETTING: Medical University Vienna/General Hospital, Vienna, Austria. PATIENTS: All neonates admitted with clinical signs of pneumothorax between July 2018 and February 2019. INTERVENTIONS: Chest radiograph and lung ultrasound in succession. MEASUREMENTS AND MAIN RESULTS: Anterior-posterior chest radiograph and lung ultrasound were compared. "Mirrored ribs" were defined as mirroring of at least one rib and intercostal muscles in B-mode in the absence of B-lines. Twenty-nine cases in 26 patients were considered. Pneumothorax was diagnosed in 55% of cases using reported signs for pneumothorax in lung ultrasound and in 31% using chest radiograph. Lung ultrasound identified all pneumothoraces visible in chest radiograph. "Mirrored ribs" were visible in all patients with signs for pneumothorax and in none without signs for pneumothorax in lung ultrasound, representing a specificity and sensitivity of 100% compared with reported signs for pneumothorax in lung ultrasound. CONCLUSIONS: The occurrence of "mirrored ribs" in lung ultrasound in combination with absence of lung sliding, absence of B-lines and lung point might facilitate the rapid recognition of pneumothorax in neonates.