1. Service of Gastroenterology and Hepatology, Geneva University Hospitals, Geneva, Switzerland
2. Service of Gastroenterology and Hepatology, Hospital S. Juan Dios del Aljarafe, Seville, Spain
3. Institute of Radiation Physics, University Hospital Center of Lausanne, Switzerland
4. Greek Atomic Energy Commission (GAEC), Agia Paraskevi, Athens, Greece
5. Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-aux-Roses, France
6. Department of Medical Physics, Faculty of Medicine, University of Crete, Iraklion, Crete, Greece
7. Department of Gastroenterology, University of Crete, Iraklion, Crete, Greece
8. Departments of Gastroenterology, Konstantopoulio-Agia Olga Hospital, Athens, Greece
9. Belgian Nuclear Research Centre (SCK-CEN), Mol, Belgium
10. Medical Physics Department, Konstantopoulio-Agia Olga Hospital, Athens, Greece