1. Department of Obstetrics and Gynecology Jichi Medical University Tochigi Japan
2. Department of Obstetrics and Gynecology Koga Red Cross Hospital Koga Ibaraki Japan
3. Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
4. Department of Surgery, and Center for Resident Education Jichi Medical University Shimotsuke Tochigi Japan