1. Department of Neurosurgery, Inje University Ilsan Paik Hospital, Ilsan, Republic of Korea
2. Department of Neurosurgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
3. Department of Neurosurgery, Gil Medical Center, Gachon University College of Medicine, Incheon, Republic of Korea
4. Department of Neurosurgery, Ajou University Hospital, Ajou University School of Medicine, Suwon, Republic of Korea
5. Department of Neurosurgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea