Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The mediastinal and hilar contours are unchanged . Extensive bullous emphysematous disease is re - demonstrated , more pronounced on the right . There may be a tiny residual right pleural effusion . Patchy opacities in the lung bases may reflect atelectasis though infection can not be completely excluded . No definite pneumothorax is identified . There are no acute osseous changes .
    OUTPUT:
    
Extensive bullous emphysema . Probable bibasilar atelectasis and residual minimal trace right pleural effusion . Infection at the lung bases can not be completely excluded .