[1] McGill Univ, Montreal Neurol Inst, Dept Neurol & Neurosurg, Montreal, PQ, Canada
[2] Shiraz Univ Med Sci, Clin Neurol Res Ctr, Shiraz, Iran
[3] Sichuan Univ, West China Hosp, Dept Neurosurg, Chengdu, Sichuan, Peoples R China
[4] Univ Southern Calif USC, Keck Sch Med, Dept Neurol Surg, Los Angeles, CA USA