Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes which limits the assessment of the lung bases . There is likely mild bibasilar atelectasis . Heart size is difficult to assess , but likely within normal limits . The mediastinal and hilar contours are unchanged . There is crowding of the bronchovascular structures but no overt pulmonary edema is present . No pleural effusion or pneumothorax is visualized . No acute osseous abnormality is seen .
    OUTPUT:
    
Low lung volumes which limits the assessment of the lung bases . Probable mild bibasilar atelectasis .