Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged . The mediastinal and hilar contours are within normal limits . There is an area of increased density projecting over the right lung base which is consistent with known thoracic aortic aneurysm . The lungs are otherwise clear . There is no focal consolidation , pleural effusion or pneumothorax .
    OUTPUT:
    
Right lung base opacity consistent with known thoracic aortic aneurysm . Otherwise , unremarkable examination .