Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size remains mildly enlarged . The mediastinal contours are unchanged . There is mild pulmonary vascular congestion . Bibasilar patchy airspace opacities may reflect atelectasis though infection or aspiration can not be excluded . No pleural effusion or pneumothorax is seen . No acute osseous abnormalities are demonstrated .
    OUTPUT:
    
Bibasilar patchy airspace opacity could reflect atelectasis but infection or aspiration are not excluded .