Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac silhouette is mildly enlarged , however , unchanged from prior examination . The mediastinal and hilar contours are within normal limits . There is mild calcification of the aortic knob . There is mild interstitial pulmonary edema . However , there is no focal consolidation , pleural effusion , or pneumothorax .
    OUTPUT:
    
Mild pulmonary edema with no evidence of pneumonia .