Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A right internal jugular central venous catheter projects with the tip at the confluence of the brachiocephalic veins . The cardiomediastinal silhouette is stable . There is a retrocardiac opacity which may reflect atelectasis , aspiration or infection . No pleural effusion or pneumothorax .
    OUTPUT:
    
Catheter with tip projecting over the confluence of the brachiocephalic veins . Retrocardiac opacity may reflect atelectasis , aspiration or pneumonia .