1. Department of Surgery, Erasmus University Medical Centre, Rotterdam, the Netherlands
2. Department of Surgery, Imelda Hospital, Bonheiden, Belgium
3. Department of Surgery, Bispebjerg Hospital, Copenhagen, Denmark
4. Department of Surgery, Elkerliek Hospital, Helmond, the Netherlands
5. Department of Surgery, University Hospital Lille, Lille, France
6. Department of Surgery, Vivantes Klinikum Spandau, Berlin, Germany
7. Department of Abdominal Surgery, University Hospital Leuven, Leuven, Belgium
8. Department of Surgery, University College London Hospital, London, United Kingdom
9. Department of Surgery, University Hospital Gent, Gent, Belgium
10. Department of Surgery, Hôpital Cochin, Paris, France
11. Department of Surgery, Isala Hospital, Zwolle, the Netherlands
12. Department of Surgery, Università di Roma Sapienza, Rome, Italy
13. Department of Surgery, IJsselland Hospital, Capelle aan den IJssel, the Netherlands
14. Department of Surgery, Chirurgische Praxis Ärztehaus, Cottbus, Germany
15. Department of Radiology, Isala hospital, Zwolle, the Netherlands.