Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are extensive heterogeneous opacities throughout the entire left lung and right lower lung . The right mid and upper lung is essentially clear . The heart size is within normal limits . The mediastinal contours are normal . There are no definite pleural effusions . No pneumothorax .
    OUTPUT:
    
Diffuse bilateral airspace opacities with sparing of the right mid / upper lung would be a somewhat unusual pattern for asymmetric pulmonary edema and it is thought to be concerning for a multifocal infectious process .