Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The mediastinal and aortic contours are similar in appearance to prior chest examination from ___ . Aortic dissection , however , can not be excluded in this examination . The right upper mediastinum appears unchanged . There is no pneumothorax or large pleural effusion . Surgical clips are seen projecting over the right breast .
    OUTPUT:
    
Stable mediastinal and aortic contours . However , dissection can not be excluded on this examination and further evaluation is recommended with a chest CT .