1. Department of Neurosurgery, Kariya Toyota General Hospital, 5-15 Sumiyoshi-cho, Kariya, Aichi, 448-8505, Japan
2. Department of Pathology, Kariya Toyota General Hospital, 5-15 Sumiyoshi-cho, Kariya, Aichi, 448-8505, Japan
3. Department of Diagnostic Pathology, School of Medicine Fujita Health University, Toyoake, Aichi, Japan