1. Department of NeurosurgeryHangang Sacred Heart Hospital, College of Medicine, Hallym University, Seoul, South Korea,
2. Department of Anatomy and Cell BiologyCollege of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea,
3. Department of AnatomyCollege of Veterinary Medicine, Kangwon National University, Chuncheon, South Korea,
4. Department of NeurobiologySchool of Medicine, Kangwon National University, Chuncheon, South Korea