Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is mildly enlarged . Mediastinal and hilar contours are unremarkable . There is crowding of the bronchovascular structures and patchy bibasilar airspace opacities are re - demonstrated . No pleural effusion or pneumothorax is identified . There are no acute osseous abnormalities .
    OUTPUT:
    
Low lung volumes limit assessment of the lung bases . Streaky bibasilar airspace opacities most likely reflect atelectasis . As before , infection or aspiration within the lung bases can not be completely excluded .