Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest are compared to previous exam from ___ . Low lung volumes seen on the frontal exam . Bibasilar opacities , larger on the left , most likely due to atelectasis , as this is not confirmed on lateral view . Lungs otherwise are clear . Cardiomediastinal silhouette is within normal limits . Surgical clips in the right upper quadrant suggest prior cholecystectomy . Osseous and soft tissue structures are otherwise unremarkable .
    OUTPUT:
    
No definite acute cardiopulmonary process .