1. Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Hokkaido, Japan
2. Faculty of Dental Medicine, Department of Radiology, Hokkaido University, Sapporo, Hokkaido, Japan
3. Department of Diagnostic Imaging, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan
4. Siemens Healthcare K.K., Tokyo, Japan
5. Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, Japan