Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The aortic arch is mildly tortuous and calcified . Irregular pulmonary architecture again suggests emphysema , as seen on the prior chest CT . There is a vague right infrahilar opacity , but similar to the prior examination suggesting minor chronic scarring or atelectasis . The lungs are hyperinflated . There is no definite pleural effusion . A mild superior endplate compression deformity along a lower thoracic vertebral body appears unchanged .
    OUTPUT:
    
Findings consistent with emphysema , but no definite acute process .