Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were obtained . Cardiomediastinal silhouette is stable . There is subtle increased retrocardiac opacification anterior to the spine , which may represent atelectasis ; however , very early consolidation can not be excluded . Pulmonary vasculature is normal . No pleural effusion or pneumothorax .
    OUTPUT:
    
Subtle increased opacification on the lateral view posterior to the heart and anterior to the spine likely represents atelectasis ; however , very early pneumonia can not be excluded .