Figure 6a. Complicated bronchogenic cyst. (a) Chest radiograph shows rounded mass with an air-fluid level, occupying the entire right middle lobe, corresponding to a bronchogenic cyst connecting with the bronchus. (b) Contrast-enhanced CT scan shows a thick-walled fluid-filled rounded mass (*) with an air-fluid level, corresponding to the infected bronchogenic cyst. Note enhancement of the cystic wall.