Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The aorta is again tortuous . The mediastinal and hilar contours appear stable . There is no pleural effusion or pneumothorax . The lungs appear clear . Mild degenerative changes again affect lower thoracic levels , not significantly changed .
    OUTPUT:
    
No evidence of acute cardiopulmonary disease .