1. From the Department of Neurosurgery (H.T., Y.M., A.M., S.M., T.A.), The Jikei University School of Medicine, Tokyo, Japan; the Graduate School of Mechanical Engineering (S.O., M.Y.), Tokyo University of Science, Tokyo, Japan; The Australian School of Advanced Medicine (Y.Q.), Macquarie University, Sydney, Australia; and Siemens Japan K.K. (A.M.), Tokyo, Japan.