Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours are unremarkable . There is no pleural effusion or pneumothorax . Patchy lingular opacity is probably due to minor scarring . Otherwise , the lungs appear clear . Moderate degenerative changes are noted along the thoracic spine .
    OUTPUT:
    
No evidence of acute disease .