1. From Department of Diagnostic Radiology (J.H., Y.J.K., H.-J.L., T.H.K., J.E.N., K.O.C., B.W.C.), Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea; Division of Cardiology (J.-W.H., E.-Y.C., C.-Y.S.), Yonsei Cardiovascular Center, Yonsei University College of Medicine, Seoul, South Korea; Department of Neurology (J.H.H.), Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea.