Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographdemonstrates a persistent area of scarring at the left lung apex which is unchanged since previous examination . The lungs are otherwise clear with persistent emphysematous changes . No pleural effusion or pneumothorax . Heart size , mediastinal contour , and hila are unremarkable . Surgical clips are again seen within the left axilla . Calcified aortic arch is again noted .
    OUTPUT:
    
1 . No pneumonia . 2 . Stable chronic left apical scarring 3 . Emphysema .