A large area of lucency within the left upper lobe has an atypical appearance for a pneumothorax given lung markings project into the inferior aspect of the lucency and an alternate aetiology such as a large bulla or congenital lobar emphysema should be considered. Linear bands of atelectasis are present within the aerated left lower lobe. The right lung is clear. An intercostal catheter is present on the left. No mediastinal shift is demonstrated.