[1] Keio Univ Hosp, Off Radiat Technol, Tokyo, Japan
[2] Ainomiyako Neurosurg Hosp, Neurorehabil Ctr, Osaka, Japan
[3] Jikei Univ, Div Regenerat Med, Grad Sch Med, Tokyo, Japan
[4] Tokyo Metropolitan Univ, Grad Sch Human Hlth Sci, Dept Radiol Sci, Tokyo, Japan