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 ___ . On today 's frontal view , lower lung volumes are seen . Bibasilar opacities may be due to atelectasis given these lower lung volumes and as they are not visualized on the lateral view . Superiorly , the lungs are clear . Cardiomediastinal silhouette is stable . There is suggestion of a posterior eighth rib fracture , however , superimposed linear vascular markings may contribute to this appearance . Other soft tissue and osseous structures are unremarkable . There are chronic changes identified at the left acromioclavicular joint which appears separated with superior subluxation of the lateral clavicle . There is adjacent dystrophic calcifications .
    OUTPUT:
    
No definite acute cardiopulmonary process . Possible posterior right eighth rib fracture vs . overlapping linear parenchymal opacities . Dedicated views can be performed if desired .