Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A right pigtail catheter has been placed in the interim with its tip projecting over the lateral aspect of the right lower hemithorax . The previously demonstrated large pleural effusion has subsequently decreased in size , now moderate . There is probably a large associated degree of relaxation atelectasis as the cardiomediastinal silhouette is shifted to the right . No evidence of pneumothorax . There is extensive air under the left hemidiaphragm which appears to lie within the stomach . No left pleural effusion . The left lung is clear .
    OUTPUT:
    
1 . Marked decrease in the size of the right pleural effusion , now moderate after placement of a pigtail catheter . 2 . Substantial right lower lung atelectasis . 3 . No pneumothorax .