1. Departments of Neurosurgery and
2. Pathology, Tohoku University Graduate School of Medicine, Sendai;
3. Department of Neurosurgery, Jiro Suzuki Memorial Gamma House, Furukawa Seiryo Hospital, Oosaki, Miyagi;
4. Department of Diagnostic Pathology, Tokyo Medical University, Hachioji Medical Center, Hachioji, Tokyo; and
5. Department of Human Pathology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan