1. Department of Neurosurgery, Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, Hwaseong, Korea.
2. Department of Neurosurgery, Kangnam Sacred Heart Hospital, College of Medicine, Hallym University, Seoul, Korea.
3. Department of Neurosurgery, Kangdong Sacred Heart Hospital, College of Medicine, Hallym University, Seoul, Korea.
4. Department of Neurosurgery, Sacred Heart Hospital, College of Medicine, Hallym University, Anyang, Korea.
5. Department of Neurosurgery, Soonchunhyang Unviersity Bucheon Hospital, Bucheon, Korea.