1. Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114.
2. Department of Radiology, Massachusetts General Hospital, Boston, MA.
3. Department of Radiology, CT Operations, Massachusetts General Hospital, Boston, MA.
4. Department of Radiology, Division of Thoracic Imaging and Intervention, Massachusetts General Hospital, Boston, MA.
5. Department of Radiology, Division of Emergency Imaging, Massachusetts General Hospital, Boston, MA.