1 Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, Rm M391, Box 0628, San Francisco, CA 94143. Electronic address: kesav.raghavan@ucsf.edu.
2 Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, Rm M391, Box 0628, San Francisco, CA 94143.
3 Virtual Radiologic, Eden Prairie, Minneapolis.
4 Department of Medical Imaging, Sutter Health, Sacramento, California.