Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Right - sided chest tube appears similarly positioned . No pneumothorax is evident on these views . Recent right upper lung postsurgical changes and remote left upper lung postsurgical changes appear similar . Opacity at the right base appears similar to minimally decreased compared to prior . Subcutaneous emphysema is minimally decreased . Sternal wires appear intact . Heart size is normal . Mediastinal contours are stable .
    OUTPUT:
    
Minimally improved aeration at the right lung base without evidence for pneumothorax .