1. Division of Radiology, Department of Medical Technology, Kochi Medical School Hospital, Nankoku, Japan
2. Department of Radiological Technology, Kochi Health Sciences Center, Kochi, Japan
3. Department of Gunma Prefectural College of Health Sciences, Maebashi, Japan
4. Department of Diagnostic and Interventional Radiology, Kochi Medical School, Kochi University, Nankoku, Japan.