Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear , although slightly hyperinflated . There is upper zone redistrubution , although the film may have been taken in a more supine position rather than upright . Calcifications of the aortic knob are present . Cardiac silhouette is normal in size . No pleural effusion or pneumothorax . No acute bony abnormalities .
    OUTPUT:
    
Mild vascular congestion , but no evidence of pneumonia .