Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate unremarkable cardiomediastinal and hilar contours . Minimal bibasilar opacifications are evident likely reflecting atelectasis . A 1 .5 - cm density projects over the right mid lung , stable compared to ___ study . Of note , on both studies , lesion projects over the anterior right fourth rib and may reflect osseous abnormality , though can not exclude parenchymal nodule . No opacification concerning for pneumonia identified . No pleural effusion or pneumothorax present . Multilevel degenerative changes identified within the thoracic spine .
    OUTPUT:
    
Bibasilar opacifications , likely reflecting atelectasis . 1 .5 - cm density projecting over the right mid lung and anterior right fourth rib . Given stable relationship to anterior fourth rib , this likely represents an ossific density , possibly degenerative change at the costochondral junction , however , can not definitively exclude pulmonary mass . Recommend reevaluation with shallow oblique radiographs to better localize the opacity .