Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the prior exam , there has been improved aeration of the right upper lobe . There is still a large right pleural effusion and associated atelectasis . The left lung is essentially clear . There is no left pleural effusion . No pneumothorax . The cardiomediastinal silhouette is normal . There is no free air below the hemidiaphragms .
    OUTPUT:
    
1 . No evidence of pneumoperitoneum . 2 . Interval improvement in the aeration of the right upper lung , likely due to a slightly decrease in size of the large right pleural effusion .