Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: 2 views were obtained of the chest . Left lower lobe opacity is similar in appearance to the ___ examination and likely reflects a combination of atelectasis and effusion though aspiration or infection can not entirely be excluded . The remainder of the lungs are clear . Pulmonary vascularity is normal . Cardiac silhouette remains mildly enlarged .
    OUTPUT:
    
Left lower lobe opacity could reflect atelectasis , though aspiration or infection can not be excluded . Small left pleural effusion .