Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The tip of the right internal jugular central venous catheter projects over the right atrium . Low bilateral lung volumes and . There is a new retrocardiac opacity likely reflective of atelectasis . No pleural effusion or pneumothorax identified . The size the cardiac silhouette is enlarged , likely exaggerated by the low lung volumes and AP technique .
    OUTPUT:
    
The tip of the right internal jugular central venous catheter projects over the right atrium . Low bilateral lung volumes . Retrocardiac opacity likely reflects postop atelectasis .