Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Tortuous and diffusely dilated thoracic aorta is re - demonstrated , with marked enlargement of the aortic knob compatible with known aortic arch aneurysm , better depicted on the prior chest CTA . Heart size is top normal . The pulmonary vascularity is not engorged . The lungs are clear without focal consolidation . No pleural effusion or pneumothorax is identified . There are no acute osseous abnormalities .
    OUTPUT:
    
Diffusely dilated and tortuous thoracic aorta with unchanged aortic arch aneurysm . No acute cardiopulmonary abnormality otherwise detected .