1. Department of Gastrointestinal Surgery, Østfold Hospital Trust, Grålum, Norway, Institute for Clinical Medicine, University of Oslo, Oslo, Norway
2. Department of Gastrointestinal Surgery, Østfold Hospital Trust, Grålum, Norway, Institute for Clinical Medicine, University of Oslo, Oslo, Norway, Interventional Centre, Oslo University Hospital-Rikshospitalet, Oslo, Norway, Department of Surgery, Fonna Hospital Trust, Odda, Norway, Department of Faculty Surgery N 2, I.M. Sechenov First Moscow State Medical University, Moscow, Russia, Department of Surgery N 2, Yerevan State Medical University After M. Heratsi, Yerevan, Armenia
3. Anatomy Sector, Teaching Unit, Faculty of Medicine, University of Geneva, Geneva, Switzerland
4. Institute for Clinical Medicine, University of Oslo, Oslo, Norway, Department of Digestive Surgery, Akershus University Hospital, Lørenskog, Norway