[1] Yerevan State Med Univ, Dept Surg N1, Yerevan, Armenia
[2] Cent Clin Mil Hosp, Dept Gen & Laparoscop Surg, Yerevan, Armenia
[3] Oslo Univ Hosp, Intervent Ctr, Rikshosp, Oslo, Norway
[4] Oslo Univ Hosp, Dept HPB Surg, Rikshosp, Oslo, Norway
[5] Med Univ Innsbruck, Dept Visceral Transplant & Thorac Surg, Innsbruck, Austria
[6] Stavanger Univ Hosp, Dept Gastrointestinal Surg, Stavanger, Norway
[7] Univ Bergen, Dept Clin Med, Bergen, Norway
[8] Univ Oslo, Inst Clin Med, Med Fac, Oslo, Norway