1. Departments of Neurosurgery and
2. Department of Neurosurgery, Ajou University School of Medicine, Suwon;
3. Radiology, Gangnam Severance Hospital, Yonsei University, Seoul;
4. Department of Neurosurgery, Inha University School of Medicine, Incheon; and
5. Departments of Radiology and
6. Neurosurgery, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Republic of Korea