Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: With exception of mild bibasilar atelectasis , the lungs are normally expanded without focal opacity to suggest pneumonia . Heart size is mildly enlarged . The mediastinal and hilar contours are unchanged . There is no pleural effusion or pneumothorax . The aorta is unfolded and tortuous .
    OUTPUT:
    
Mild bibasilar atelectasis . No evidence of pneumonia .