Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest demonstrate low lung volumes with resulting bronchovascular crowding . Increased opacification of the left base suggests atelectasis . The cardiomediastinal and hilar contours are unchanged . There is no pneumothorax , pleural effusion , or consolidation . There are old healed left posterior rib fractures .
    OUTPUT:
    
Increased opacification at the left base suggests atelectasis .