1. Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan
2. Department of Otolaryngology-Head and Neck Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan
3. The Global Station for Quantum Medical Science and Engineering, Global Institution for collaborative research and education, Sapporo, Japan
4. Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
5. Departments of Radiology, Otolaryngology-Head and Neck Surgery, and Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA, USA