[1] Wake Forest Sch Med, Dept Radiol, Winston Salem, NC 27157 USA
[2] Univ Calif San Francisco, UCSF Benioff Childrens Hosp, Dept Radiol & Biomed Imaging, San Francisco, CA 94143 USA
[3] Univ Washington, Sch Med, Dept Radiol, Seattle, WA 98195 USA
[4] Univ Calif San Francisco, Sch Med, San Francisco, CA USA
[5] Eastern Virginia Med Sch, Dept Radiol, Norfolk, VA 23501 USA
[6] Emory Univ, Dept Radiol & Imaging Sci, Sch Elect & Comp Engn, Georgia Inst Technol, Atlanta, GA 30322 USA