Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . There is slight unfolding of the thoracic aorta . Otherwise the mediastinal and hilar contours appear unchanged . The lungs appear clear . There are no pleural effusions or pneumothorax . The chest is mildly hyperinflated . Slight degenerative changes are noted along the thoracic spine .
    OUTPUT:
    
No evidence of acute disease .