Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Diffuse bilateral patchy airspace opacities , most pronounced in the left lower lung zone may reflect pulmonary edema although superimposed infection can not be excluded . The size of the cardiomediastinal silhouette is significantly enlarged . No discrete pneumothorax identified .
    OUTPUT:
    
Diffuse bilateral airspace opacities with a markedly enlarged cardiomediastinal silhouette may reflect pulmonary edema . No discrete pneumothorax identified .