Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lateral view is limited secondary to patient 's arms being down by his side . Best seen on the frontal view is increased opacity in left mid to lower lung . They appear more conspicuous compared to recent exam from ___ for similar compared to previous exams from ___ . There is no effusion . The cardiomediastinal silhouette is stable . No acute osseous abnormalities identified . Old left rib fractures are again noted .
    OUTPUT:
    
Left mid to lower lung opacity best seen on the frontal exam which could be any combination of aspiration or infection and possible component of atelectasis .