1. From the Departments of Emergency Medicine (K.S.Z.), Radiology (S.K.), Medicine (D.B.S.), and Pathology (P.A.R.B.), Massachusetts General Hospital, and the Departments of Emergency Medicine (K.S.Z.), Radiology (S.K.), Medicine (D.B.S.), and Pathology (P.A.R.B.), Harvard Medical School — both in Boston.