Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is top normal . The mediastinal and hilar contours are unremarkable . The lungs are well expanded and clear . There is evidence of prior left mastectomy . There is no pulmonary edema , pleural effusion or pneumothorax . The osseous structures are unremarkable .
    OUTPUT:
    
No rib fractures .