Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs remain hyperinflated . Patchy medial left base opacity , increased since the prior study , could be due to atelectasis , aspiration , or pneumonia . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Persistently hyperinflated lungs may be due to COPD . Patchy medial left base opacity , increased since the prior study , and could be due to atelectasis , aspiration , or pneumonia .