Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . Subtle linear opacities in the lung bases are likely related to atelectasis . However , there is also increased density overlying the lower thoracic spine on the lateral view and the possibility of a focus of aspiration or pneumonia can not be excluded . No CHF , effusion , or pneumothorax . The heart is not enlarged . The thoracic aorta follows a tortuous course . Right paratracheal opacity likely represents vascular structures , accentuated by slight patient rotation and other technical factors . Surgical clips are visualized within the right upper quadrant .
    OUTPUT:
    
1 ) Bibasilar atelectasis . 2 ) Increased density overlying the lower thoracic spine on the lateral view -- aspiration or pneumonia can not be excluded .