Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are unchanged compared to the prior study . There is persistent moderate cardiomegaly . The right upper lobe airspace opacity now appears more confluent with air bronchograms . This could reflect asymmetric pulmonary edema but infection can not be excluded . No pneumothorax or pleural effusion seen . The visualized bony structures are unremarkable in appearance .
    OUTPUT:
    
Airspace opacity in the right upper lobe may reflect asymmetric pulmonary edema versus infection .