Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged . The mediastinal and hilar contours appear unchanged . A prominent pericardial fat pad is present , but otherwise aside from patchy bibasilar atelectasis , the lungs appear clear . There is no pleural effusion or pneumothorax . Hyperinflation is present .
    OUTPUT:
    
No evidence of pneumonia .