Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to the prior study , subsegmental atelectasis at both bases is significantly increased . The possibility of associated early infiltrates can not be excluded , though no frank consolidation is seen . The cardiomediastinal silhouette is unchanged . There is mild vascular plethora , without overt CHF . No effusion .
    OUTPUT:
    
Increased streaky opacities at both bases are most suggestive of increased bibasilar atelectasis . The possibility of early infectious infiltrates is considered less likely , but can not be entirely excluded . Mild upper zone redistribution again seen . Doubt overt CHF .