1. From the Department of Radiology (D.-H.K., Y.-S.K.), Department of Neurosurgery (J.P.), Kyungpook National University Hospital, Daegu, Korea; and Department of Radiology (B.M.K., D.J.K., S.H.S., D.I.K.), Department of Neurosurgery (S.K.H., J.W.L., Y.B.K.), Yonsei University College of Medicine, Seoul, Korea.