[1] Osaka Med Coll, Dept Neurosurg, Osaka, Japan
[2] Okayama Univ, Dept Neurosurg, Okayama, Japan
[3] Japan Atom Energy Agcy, Tokai, Japan
[4] Osaka Prefectural Univ, Dept Agr, Sakai, Osaka, Japan
[5] Canc Intelligence Care Syst Inc, Minati Ku, Tokyo, Japan
[6] Kyoto Univ, Inst Res Reactor, Osaka 59004, Japan