Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . The heart is normal in size . The aorta is mildly tortuous and calcified . Otherwise , the cardiac , mediastinal and hilar contours appear within normal limits . Streaky left basilar opacity suggests minor atelectasis . Elsewhere , the lungs appear clear . There are no pleural effusions or pneumothorax . Moderate - to - severe narrowing is noted along a lower thoracic interspace with subchondral sclerosis .
    OUTPUT:
    
Patchy left basilar opacity probably due to minor atelectasis , otherwise unremarkable .