Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . The heart is normal in size . The mediastinal and hilar contours are unremarkable . The lungs appear clear . There are no pleural effusions or pneumothorax . Mild - to - moderate degenerative changes are noted along the mid thoracic spine . The patient is status post partly visualized left shoulder replacement .
    OUTPUT:
    
No evidence of acute disease .