Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval development of relatively extensive airspace opacity in the left mid lung . No silhouetting of the left heart border likely reflecting left lower lobe consolidation . There is a probable small left pleural effusion . The right lung appears grossly clear . The cardiomediastinal contour is unchanged compared to the prior study allowing for differences in imaging technique . No pneumothorax seen .
    OUTPUT:
    
Interval development of consolidation in the left lower lung , likely left lower lobe .