Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear within normal limits aside from mild unfolding along the descending thoracic aorta and patchy calcification along the arch . The lungs appear clear . There are no pleural effusions or pneumothorax . Small - to - moderate osteophytes are noted along the mid - to - lower thoracic spine . There has been no significant change .
    OUTPUT:
    
No evidence of acute disease .