Abstract
Pneumomediastinum is a relatively rare and usually a self-limiting condition in infants. However, it can lead to tension pneumomediastinum or pneumothorax, which may rapidly become life-threatening. Therefore, its timely and accurate detection is important and close follow-up to resolution is needed. Ultrasound can be used as a real-time problem solver to accurately diagnose pneumomediastinum in an infant and should be encouraged as a radiation-free adjunct imaging modality when radiography cannot provide a definite diagnosis. We present a case of a 13-month-old preterm girl with bronchopulmonary dysplasia and acute respiratory infection who presented with sudden respiratory failure due to spontaneous pneumomediastinum. Pneumomediastinum was eventually diagnosed with ultrasound, after chest radiography performed during the on-call hours was misinterpreted because not all typical radiographic signs of pneumomediastinum were present.