Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Marked interstitial abnormality with upper lobe predominant nodular opacities are not appreciably changed since the study of 3 days prior . Upper lobe scarring is unchanged , and is likely a sequela of prior TB infection . Slightly increased interstitial prominence is most likely due to pulmonary edema . There is no pneumothorax . The heart and mediastinum are within normal limits despite the projection . Metallic right upper quadrant surgical clips are incidentally noted .
    OUTPUT:
    
Mild pulmonary edema superimposed on chronic changes as described above .