1. From the Departments of Radiology (D.B.G., D.B.V.) and Surgery (T.B.R.), University of Colorado School of Medicine, 12401 E 17th St, Mailstop L954, Aurora, CO 80045; Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (C.A.R.); Premier Radiology, Tupelo, Miss (W.R.J.); and Department of Radiology, Weill Cornell Medicine, New York, NY (Q.A.T.).