1. From the Department of Radiology (M.A.P., A.D.T.A., L.W., P.J.N., S.K.V.), Department of Laboratory Medicine and Pathology (A.J.W.), and Department of Hematology-Oncology (A.D.), Mayo Clinic, 200 First St SW, Rochester, MN 55905; Department of Radiology, Mayo Clinic, Jacksonville, Fla (L.F.A., J.D.L.); and Department of Radiology, Mayo Clinic, Phoenix, Ariz (A.K.).