Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were obtained . Subtle opacities in the lower lungs may represent atelectasis , though can not exclude a very early pneumonia . No large pleural effusion or pneumothorax is seen . Cardiomediastinal silhouette is normal . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Bibasilar opacities , most compatible with atelectasis , though an early pneumonia can not be excluded .