Imaging neonatal spontaneous pneumomediastinum using ultrasound

PURPOSE: To evaluate the feasibility of ultrasound in detecting spontaneous pneumomediastinum in the neonatal intensive care unit (NICU) and illustrate the ultrasound features. METHODS: Among neonates with abnormal mediastinal radiolucency suspected on chest radiography, those referred for ultrasound examination within 2 days were included. Anterior mediastinal ultrasound was performed using a linear transducer (5–12 MHz) to determine the presence and location of abnormal air in the mediastinum. Clinical data for the neonates were also reviewed. RESULTS: On ultrasound, pneumomediastinum appeared as thick linear/curvilinear echogenic lines, some with posterior shadowing located between the anterior chest wall and thymus, in lateral margins of the thymus, between the thymus and the great vessels, and in the middle of the thymic parenchyma. CONCLUSIONS: Using ultrasound, pneumomediastinum was easily visualized, and localization of the abnormal air accumulation was possible. Ultrasound may be used as a radiation-free supplementary imaging modality for neonates with abnormal mediastinal air.