Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . There is possible background COPD , with mild parenchymal scarring . No chf , focal infiltrate , effusion , or pneumothrax is detected . Heart size is borderline , with mild unfolding of the aorta . No subdiaphragmatic free air is identified .
    OUTPUT:
    
1 ) Possible background COPD , with mild parenchymal scarring . 2 ) No acute pulmonary process identified . 3 ) No subdiaphgramatic air identified .