1 Mercy Children's Hospital, West County Radiological Group, Inc, 615 S. New Ballas Rd, St. Louis, MO 63141 (S.G.F.). Electronic address: [email protected].
2 Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (J.D.C.).
3 University of Chicago Pritzker School of Medicine, Chicago, Illinois (C.M.S.).
4 Department of Radiology, Lucile Packard Children's Hospital, Stanford University, Palo Alto, California (R.A.B.).