Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Improved bilateral lung volumes . Linear opacities in bilateral lung bases likely scarring rather than atelectasis and unchanged since ___ . No focal consolidation . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are unremarkable .
    OUTPUT:
    
No evidence of pneumonia . Stable bibasilar scarring .