1. From the Department of Radiology, Mayo Clinic, Rochester, MN 55905 USA (K.R., A.F., F.B., F.E.D., L.Y., P.R., J.G.F., S.L., C.H.M.), Siemens Healthineers, Forchheim, Germany (M.P., A.H., B.S., T.G.F.) and Siemens Medical Solutions, Malvern, PA, USA (E.R.S.)