1. From the Departments of Radiology (S.L.A., J.H.P., C.M.M., P.A.D., J.L.S., J.J.M., A.R.P., X.Z.), Family Medicine (D.A.M.), and Dermatology (N.N.F.), University of Iowa, 200 Hawkins Dr, Iowa City, IA 52246; and Department of Radiology, Iowa City Veterans Health Care System, Iowa City, IA (J.H.P.).