Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unchanged . The pulmonary vasculature is normal . Lungs are clear . Pulmonary vasculature is normal . No pleural effusion or pneumothorax is present . There are mild degenerative changes in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .