Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low causing bronchovascular crowding ; however , there does appear to be mild edema . No focal opacity to suggest pneumonia is seen . No pleural effusion or pneumothorax is identified . There is mild cardiomegaly and tortuosity of the aorta .
    OUTPUT:
    
No evidence of pneumonia . Mild edema .