Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The heart size is normal . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is not engorged . Patchy opacities in the lung bases could reflect atelectasis but infection or aspiration can not be completely excluded . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
Patchy bibasilar airspace opacities could reflect atelectasis but infection or aspiration is not excluded .