Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperexpanded , with diffuse hyperlucency , flattening of the diaphragm , and widening of the retrosternal clear space . Right middle lobe atelectasis has resolved . Cardiomediastinal and hilar contours are normal . There are no pleural effusions , pneumothorax , or pneumomediastinum . There is an old healed fracture of the right ninth posterior rib .
    OUTPUT:
    
COPD . No acute process .