1. From the Department of Diagnostic and Interventional Radiology, University Hospital Cologne, Cologne, Germany (S.L., M.L.B., D.Z., N.G.H., N.A., K.R.L., S.H., J.B., D.M., T.P.); and Department of Radiology, Case Western Reserve University and University Hospitals, Cleveland, Ohio (N.G.H., K.R.L.).