Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Significantly increased right lower lung opacities superimposed on chronic interstitial disease . Excepting chronic interstitial findings , the left lung is grossly clear . No pleural effusion . No pneumothorax . Heart size is top - normal . Chronic posterior right third and fifth rib fractures are again noted .
    OUTPUT:
    
Possible right lower lobe pneumonia superimposed on chronic pulmonary disease , less likely asymmetric pulmonary edema .