1. From the Department of Radiology, Division of Emergency Radiology (J.S., A.C., M.L.L., M.H.S.), Department of Psychiatry and Behavioral Sciences (M.L.L.), and Dominick P. Purpura Department of Neuroscience (M.L.L.), Montefiore Medical Center, Albert Einstein College of Medicine, 111 E 210th St, Bronx, NY 10467; Department of Radiology, Rutgers New Jersey Medical School, Newark, NJ (R.J.D.); and Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Conn (M.S., M.V.R.).