Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Region of consolidation identified in the retrocardiac region which silhouettes the descending thoracic aorta . Blunting of posterior costophrenic angle suggests small effusions . Elsewhere , the lungs are clear . Cardiac silhouette is the mildly enlarged . No acute osseous abnormalities detected .
    OUTPUT:
    
Retrocardiac opacity potentially due to atelectasis however lower lobe pneumonia is also possible . Small bilateral effusions .