Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Streaky bibasilar opacities are in keeping with atelectasis . Heart size is top normal but stable . Mediastinal surgical clips are unchanged in location . Irregular contour of the aortic knob is likely secondary to the previously imaged aortic arch aneurysm . No pleural effusion or pneumothorax .
    OUTPUT:
    
1 . Mild bibasilar atelectasis . 2 . Irregular appearance of the aortic knob in keeping with known saccular aortic arch aneurysm . 3 . Otherwise no acute cardiopulmonary process .