1. The University of Chicago, Department of Radiology, Chicago, Illinois
2. Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen
3. University of Michigan, Department of Radiology, Ann Arbor, Michigan
4. Frederick National Laboratory for Cancer Research, Cancer Imaging Program, Frederick, Maryland
5. U.S. Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, Maryla
6. National Cancer Institute, Cancer Imaging Program, Division of Cancer Treatment and Diagnosis, Bethe
7. MGH/Harvard Medical School, Boston, Massachusetts