Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is retrocardiac opacity as well as faint opacity at the right lung base . Superiorly , the lungs are clear . The cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities . Hardware seen in the left humerus and surgical clips are noted in the right upper quadrant .
    OUTPUT:
    
Bibasilar opacities , left greater than right which could be in part due to atelectasis although superimposed aspiration or infection are entirely possible . Repeat with improved inspiratory effort may help further characterize .