1. From the Department of Radiology and Imaging Sciences, Emory University School of Medicine, Emory University Hospital, 1364 Clifton Road, Suite BG20, Atlanta, GA (A.V.T.); Department of Radiology, New York University School of Medicine, New York, NY (E.K.); and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Mass (S.I.L.).