Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size , mediastinal and hilar contours are normal . A questionable area of increased opacity is observed in the right infrahilar region on the frontal radiograph , without a definitive correlate on the lateral view . A small linear opacity in the retrocardiac region is unchanged since ___ and probably due to focal scarring . Lungs are otherwise clear , and there are no pleural effusions or acute skeletal findings .
    OUTPUT:
    
Nonspecific opacity in right infrahilar region , not fully characterized by chest radiography . If persistent on short - term followup chest x-rays , consider chest CT for more complete evaluation .