1. Departments of Pathology, Chungbuk National University Hospital, Cheongju, South Korea;
2. Departments of Neurosurgery, Chungbuk National University Hospital, Cheongju, South Korea;
3. Chungbuk National University College of Medicine, Cheongju, South Korea;
4. Departments of Radiology, Chungbuk National University Hospital, Cheongju, South Korea