Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is some residual opacity in the lingula which has significantly decreased since prior exam . There is no new consolidation . Cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities .
    OUTPUT:
    
Small residual lingular opacity could represent sequela of prior infection although superimposed component of acute infection is hard to exclude .