1. From the Departments of Medicine (M.W.A., W.L., S.J.L., P.A., S.D.C., X.Y., S.A.W.), Neurology, and Pediatrics (A.M.C.), and Biomedical Engineering (W.L., X.Y., S.A.W.), Washington University School of Medicine, St Louis, Mo, and Philips Medical Systems, Best, Netherlands (S.D.C.).