Fig. 1
From: Imaging features and differential diagnoses of non-neoplastic diffuse mediastinal diseases
Atraumatic pneumomediastinum. A patient with sudden spontaneous retrosternal and interscapular pain. Frontal chest X-ray (a), coronal oblique reformation in lung windowing (b), and axial slices (c, d) show gas outlining the mediastinal structures, with pneumopericardium (orange arrows in a and d) appearing as a left paracardiac subtle line in a and subcutaneous emphysema. Note the right aortic arch. Conservative management led to a favorable outcome