Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The aortic arch is calcified . The mediastinal and hilar contours are unremarkable . The lungs appear clear . There are no pleural effusions or pneumothorax . Bony structures are unremarkable aside from slight mid thoracic degenerative changes .
    OUTPUT:
    
No evidence of acute disease .