Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are opacities projecting over lung bases , most conspicuous at the left lung base obscuring the left lateral costophrenic angle . There is no effusion . The cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities identified .
    OUTPUT:
    
There are left greater than right basilar opacities most conspicuous at the left costophrenic angle , some of this was present on prior although is more conspicuous on the current exam and may represent active disease versus scar or atelectasis .