<prompt> Pulmonary mycetomas on radiographs most commonly show asAir fluid levelLucent crescentEccentric noduleRim calcification  <response>: The fungal ball produces a tumor-like opacity on X ray,but can be distinguished from a carcinoma by the presence of a crescent of air between the fungal ball and the upper wall of the cavityAir crescent sign.HRCT is more sensitive. Reference:Davidsons Medicine-22nd edition,page no:698. 