Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes . Prominence and indistinctness of the hila with perihilar alveolar opacities consistent with moderate pulmonary edema . Additional right middle lobe opacity could be due to atelectasis adjacent to large hiatal hernia or pneumonia . There is a large hiatal hernia with retrocardiac air - fluid level seen . No pneumothorax is seen . The cardiac silhouette is top - normal . Mediastinal contours are grossly stable . Evidence of DISH is seen along the spine .
    OUTPUT:
    
Moderate pulmonary edema . Right middle lobe opacity may be due to atelectasis adjacent to large hiatal hernia versus pneumonia .