1. Department of Radiology , Boston University School of Medicine, Boston, Massachusetts, USA
2. Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, Massachusetts, USA; Department of Radiology, Bridgeport Hospital, Yale University School of Medicine, Bridgeport, Connecticut, USA
3. Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, Massachusetts, USA; Department of Radiology, Bridgeport Hospital, Yale University School of Medicine, Bridgeport, Connecticut, USA
4. Department of Radiology, Jikei University School of Medicine, Tokyo, Japan
5. Department of Radiology, Jikei University School of Medicine, Tokyo, Japan
6. Department of Radiology, University of California at San Francisco, San Francisco, California, USA
7. Department of Nuclear Medicine and Molecular Imaging Center Universite de Paris XII , Creteil, France
8. Universite de Paris XII , Creteil, France
9. Quantitative Imaging Center, Department of Radiology, Boston University School of Medicine, Boston, Massachusetts, USA