Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is mild cardiomegaly . There is mild tortuosity of the aorta , otherwise the hilar and mediastinal contours are normal . Linear retrocardiac opacity may be atelectasis . Lungs are otherwise clear . Blunting of the lateral left costophrenic angle may be due to fat pad . Posterior costophrenic angles are relatively sharp , perhaps minimal blunting on the right . There is no evidence of a pneumothorax . Note is made of left breast implant . The visualized osseous structures are unremarkable .
    OUTPUT:
    
Mild cardiomegaly . Linear retrocardiac opacity , potentially atelectasis although infection is not entirely excluded .