Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . The heart size remains mildly enlarged . There is re- demonstration of superior mediastinal widening , due to a combination of a tortuous thoracic aorta and focal aneurysmal dilatation of the descending thoracic aortic , better assessed on the previous CT . Hilar contours are unchanged , and pulmonary vasculature is normal . Lungs are clear without focal consolidation . No pleural effusion or pneumothorax is present . There are no acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary abnormality . Unchanged widening of the superior mediastinum , attributable to a tortuous thoracic aorta and known focal aneurysm of the descending thoracic aorta .