Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperexpanded compatible with emphysema . There is increased opacity at the lateral left lung base , increased from prior , seen on the frontal view , not well substantiated on the lateral view . No pleural effusion or pneumothorax is seen . The pulmonary hila are prominent , dating back to ___ and may reflect enlarged pulmonary arteries based on prior chest CT of ___ . The cardiomediastinal contours are within normal limits with mild tortuosity of the thoracic aorta and minimal calcification of the aortic knob .
    OUTPUT:
    
1 . Increased opacity at the lateral left lung base , increased from prior , best seen on the frontal view . Findings could relate to overlying soft tissue , but consolidation due to infection is not excluded . 2 . Unchanged prominence of the bilateral hila reflecting enlarged pulmonary arteries as seen on prior CT of ___ . 3 . Emphysema .