Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: New retrocardiac opacity may reflect atelectasis or consolidation in the proper clinical context . No pleural effusion or pneumothorax identified . The size the cardiac silhouette is within normal limits . A surgical drain projects over the left upper quadrant .
    OUTPUT:
    
New retrocardiac opacity may reflect atelectasis or consolidation in the proper clinical context .