[1] Childrens Hosp Philadelphia, Dept Radiol, Philadelphia, PA 19104 USA
[2] Univ Florida, Coll Med, Dept Radiol, Gainesville, FL 32610 USA
[3] Temple Univ Hosp & Med Sch, Dept Radiol, Philadelphia, PA 19140 USA
[4] Univ Massachusetts, Dept Radiol, Med Sch Baystate, Springfield, MA USA
[5] Univ Toronto, Dept Med Imaging, Toronto, ON, Canada
[6] Univ Penn, Sch Med, Dept Radiol, Philadelphia, PA 19104 USA
[7] Wake Forest Sch Med, Dept Radiol, Winston Salem, NC 27101 USA
[8] Univ Michigan, Dept Radiol, Sch Med, Ann Arbor, MI 48109 USA
[9] Vanderbilt Univ, Med Ctr, Dept Radiol & Radiol Sci, Nashville, TN 37232 USA
[10] Vet Hlth Adm Tennessee Valley Healthcare Syst Ger, Educ Clin Ctr, Nashville, TN USA
[11] Yale Univ, Sch Med, Dept Radiol & Biomed Imaging, New Haven, CT USA
[12] Univ Massachusetts, Sch Med, Dept Radiol, 55 Lake Ave North, Worcester, MA 01655 USA