1. Department of Radiology, Stanford University School of Medicine, 300 Pasteur Dr, Rm H1307, Stanford, CA 94305.
2. Department of Radiology, Duke University Medical Center, Durham, NC.
3. Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, NC.
4. Siemens Healthcare, Malvern, PA.
5. Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC.