Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The mediastinal and hilar contours appear unchanged . There is similar vague asymmetric opacification in the left perihilar region , but elsewhere the lungs appear clear . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Equivocal vague left perihilar opacity . If pulmonary symptoms are present or persist , short - term followup radiographs may be helpful to evaluate further , although allowing for differences in technique , there has been no definite change .