Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are chronic changes at the left lung base , with blunting of the costophrenic angle . The lungs are well inflated and clear . Heart size is top - normal , stable , and mediastinal contours are normal . Aortic arch is considerably calcified . Osseous structures are intact . No foreign bodies appreciated in the airway .
    OUTPUT:
    
1 . Chronic changes at the left lung base . 2 . No foreign body appreciated in the airways .