[1] Nordland Hosp Trust, Dept Surg, Bodo, Norway
[2] Univ Tromso, Inst Clin Med, Tromso, Norway
[3] Univ Hosp Tromso, Dept Ophthalmol, Tromso, Norway
[4] Nordland Hosp Trust, Dept Res, Bodo, Norway
[5] Ullevaal Univ Hosp, Dept Surg, Oslo, Norway
[6] Oslo Univ Hosp, Intervent Ctr, Dept Hepatopancreatobiliary Surg, Oslo, Norway
[7] Univ Oslo, Inst Clin Med, Oslo, Norway
[8] Univ Tromso, Inst Comp Sci, Tromso, Norway
[9] Akershus Univ Hosp, Dept Surg, Oslo, Norway
[10] Univ Oslo, Div Surg, Campus Ahus, Oslo, Norway
[11] Dept Surg, Pk Veien 95, N-8005 Bodo, Norway