Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Clear lungs bilaterally without pleural effusion or pneumothorax . Heart size , mediastinal contour , and hila are normal . No bony abnormality .
    OUTPUT:
    
Normal chest radiographs . Results were conveyed via telephone to Dr . ___ by Dr . ___ on ___ at 11 :45 a .m . within 20 minutes of observation of findings .