Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest . The cardiomediastinal and hilar structures and contours are unchanged . Slightly better lung volumes from prior study . There is no pleural effusion . There are bilateral interstitial opacities likely representing mild interstitial edema . A more confluent opacity in the retrocardiac area may represent pneumonia .
    OUTPUT:
    
Likely mild interstitial edema . More confluent opacity in retrocardiac area may represent pneumonia .