1. Department of Medicine, Department of Radiology, University of California, San Diego, 200 W Arbor Dr, San Diego, CA 92103
2. Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Tex
3. Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Canada
4. Department of Radiology, Einstein Medical Center, Philadelphia, Pa
5. Division of Internal Medicine, University and General Hospital S. Orsola-Malpighi, University of Bologna, Bologna, Italyǁ
6. Department of Radiology, Thomas Jefferson University, Philadelphia, Pa
7. Department of Internal Medicine 2, Caritas Krankenhaus, Bad Mergentheim, Germany
8. Department of Radiology, University of Calgary, Calgary, Canada††