1. Department of Neurosurgery, Fujita Health University School of Medicine, Toyoake 470-1192, Aichi, Japan
2. Department of Radiology, Fujita Health University School of Medicine, Toyoake 470-1192, Aichi, Japan
3. Canon Medical Systems Corporation, Otawara 324-8550, Tochigi, Japan
4. Department of Diagnostic Pathology, Fujita Health University School of Medicine, Toyoake 470-1192, Aichi, Japan
5. Department of Pathology, Fujita Health University School of Health Sciences, Toyoake 470-1192, Aichi, Japan