Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The main pulmonary artery contour appears prominent , and central pulmonary arteries in the right hilum also appear slightly prominent . There is no definite pleural effusion or pneumothorax . The lungs appear clear .
    OUTPUT:
    
No frank pulmonary edema , although the main pulmonary artery appears enlarged .