1. From the Department of Neurosurgery (H.N., K.U., T.K.) and Department of Pathology (A.K.), Tokyo University School of Medicine, Tokyo; the Fuji Brain Institute (H.S., Y.S.), Shizuoka; the Showa General Hospital (K.N.), Kodaira; and Asahikawa Redcross Hospital (H.K.), Asahikawa, Japan.