In the context of mediastinal emphysema/pneumomediastinum, the main aetiologies are associated with oesophageal perforation, lung pathology or post head and neck surgery related. The main way to differentiate the pathologies would be through Computed Tomographic Imaging of the Thorax and abdomen with oral and intravenous contrast in the context of triple phase imaging. The causes of pneumomediastinum should be differentiated between traumatic and non-traumatic. Oesophageal perforation (Boerhaave syndrome) is associated with Mackler’s triad in upto 50% of patients (severe retrosternal chest pain, pneumomediastinum, mediastinitis). Whereas in cases of lung pathology this can be associated with pneumothorax and pleural effusion.