Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperinflated . Biapical scarring is noted . Left pleural effusion is moderate in size with associated compressive lower lobe atelectasis . Overall appearance is similar to prior . Mediastinal contours are unchanged . Heart size is grossly stable , however obscured by the left pleural effusion . Osseous structures are intact . No pneumothorax .
    OUTPUT:
    
Moderate left pleural effusion , with associated compressive lower lobe atelectasis , difficult to exclude a superimposed pneumonia .