1. From the Department of Medicine, Newton-Wellesley Hospital, Newton (M.D.G.), and the Departments of Radiology (D.P.M.), Medicine (A.W., M.B.B.), and Pathology (J.A.V.), Massachusetts General Hospital, and the Departments of Radiology (D.P.M.), Medicine (A.W., M.B.B.), and Pathology (J.A.V.), Harvard Medical School, Boston — all in Massachusetts.