Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . There is similar calcification and unfolding along the thoracic aorta . The mediastinal and hilar contours appear unchanged , allowing for differences in technique . There is no evidence for pleural effusion or pneumothorax . The lungs appear clear . Slight degenerative changes are similar along the thoracic spine .
    OUTPUT:
    
No evidence of acute disease .