Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest were provided . There is diffuse pulmonary edema , increased from prior exam . Difficult to exclude a left pleural effusion . No large pneumothorax . Heart size can not be assessed . Atherosclerotic calcification at the aortic knob again noted . Bony structures appeared grossly unchanged .
    OUTPUT:
    
Severe pulmonary edema .