1. Department of Radiology, Columbia University Medical Center, 630 W 168th St, PH-1, New York, NY 10032.
2. Department of Radiology, Massachusetts General Hospital, Boston, MA.
3. Department of Surgery, NewYork-Presbyterian/Columbia University Medical Center/Morgan Stanley Children's Hospital, New York, NY.
4. Department of Radiology, University of California, San Diego, San Diego, CA.
5. Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA.
6. Department of Surgery, Mayo Clinic, Rochester, MN.
7. Department of Radiology, Mayo Clinic, Rochester, MN.