1. Department of Neurosurgery, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
2. Department of Neurosurgery, Kyungpook National University Chilgok Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
3. Department of Pathology, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.