Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The aorta is mildly tortuous . Mediastinal and hilar contours are otherwise unremarkable . The pulmonary vasculature is normal . Lungs are clear . No pleural effusion or pneumothorax is demonstrated . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .