Rounded atelectasis (also known as Blesovsky’s or folded lung syndrome) develops from infolding of thickened visceral pleura with collapse of the intervening lung parenchyma.[1] It presents radiographically as a mass and may be mistaken for a tumour. On a CT scan of the chest it appears as a rounded mass like opacity in the peripheral lung adjacent to thickened pleura and with curvilinear opacities which are the bronchi and vessels (comet tail).[16] Rounded atelectasis is the least common asbestos-related benign pleural disease. Exposure to asbestos is the most likely cause today but it can occur following other medical conditions.