Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The heart remains mild to moderately enlarged but unchanged . The mediastinal and hilar contours are stable , with mild calcification at the aortic knob again demonstrated . Mild to moderate hiatal hernia is also unchanged . There is mild pulmonary edema . No focal consolidation , pleural effusion or pneumothorax is seen . Degenerative changes of the thoracic spine are redemonstrated .
    OUTPUT:
    
Mild pulmonary edema .