Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are normally expanded and clear . The heart is top normal . The mediastinal and hilar contours are normal . Specifically , appearance of the aortic arch and contour of the descending aorta is within normal limits , similar to the prior study . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
No evidence of acute cardiopulmonary abnormality .