Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There increased opacities at both bases . The right lower lobe is improved in aeration compared to the prior exam but the left lower lobe laterally is slightly worse . there are also increased opacities at both apices . The cardiac and mediastinal silhouettes are normal . Old rib fractures are again seen in the right posterior lateral lower ribs .
    OUTPUT:
    
Increased opacities at both bases could be due to volume loss or infiltrate .