Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged . Mild unfolding is noted along the thoracic aorta . Allowing for differences in technique , with lower lung volumes on this study , the cardiac , mediastinal and hilar contours appear unchanged . Streaky right mid lung opacity suggests minor atelectasis or scarring . Otherwise , the lungs appear clear . There is no pleural effusion or pneumothorax . Mild degenerative changes are similar along the mid thoracic spine .
    OUTPUT:
    
No evidence of acute disease .