[1] Catholic Univ Korea, Seoul St Marys Hosp, Dept Neurosurg, Coll Med, 222 Banpo Daero, Seoul 06591, South Korea
[2] Catholic Univ Korea, Seoul St Marys Hosp, Dept Neurol, Coll Med, Seoul, South Korea
[3] Catholic Univ Korea, Seoul St Marys Hosp, Dept Surg, Coll Med, Seoul, South Korea