Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left mid and lower lung airspace opacity most likely represents acute pneumonia . Ill - defined right lower lung airspace opacities may represent extension of the left - sided infectious process , aspiration , or atelectasis . A right posterior seventh rib deformity is unchanged from ___ . An irregular contour of the medial left first rib is similar to the prior study . Allowing for differences in technique , the cardiomediastinal silhouette is likely unchanged . There is no pulmonary edema or pneumothorax .
    OUTPUT:
    
1 . Extensive left mid and lower lung airspace opacification most likely represents an acute pneumonia . 2 . Right lower lung airspace opacity may represent infection , aspiration , or atelectasis .