Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with ___ at 09 :41 hand allowing for differences in technique , there has been slight clearing of the alveolar opacities in both lungs , suggesting improving CHF . Considerable CHF remains present . The cardiomediastinal silhouette is enlarged , but unchanged . Clips and relative lucency at the left upper lung are again seen . No well - defined pneumothorax is identified , but the possibility of a trace residual pneumothorax would be difficult to exclude . No gross effusion .
    OUTPUT:
    
Slight interval improvement in CHF findings . No obvious pneumothorax .