1. From the Department of Biomedical Engineering (X.L., K.M.S.U., S.K., E.A., G.Y., Q.Z.), Division of Surgery, Barnes-Jewish Hospital (W.C., S.H., M.M.), and Department of Electrical and System Engineering (H.L.), Washington University in St. Louis, 1 Brookings Dr, Mail Box 1097, St Louis, MO 63130; Department of Pathology (D.C.) and Mallinckrodt Institute of Radiology (A.S., Q.Z.), Washington University School of Medicine, St Louis, Mo.