Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . Mediastinal and hilar contours are unchanged . Mild atherosclerotic calcification of the aortic knob is demonstrated . Pulmonary vasculature is normal . Lungs are clear . No pleural effusion or pneumothorax is demonstrated . Anterior osteophytes are again demonstrated within the mid and lower thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .