[1] Aberdeen Royal Infirm, Dept Surg, Ward 31, Aberdeen AB25 2ZA, Scotland
[2] Hop Layne, Dept Gynaecol Surg, Mont De Marsan, France
[3] Jesi Hosp, Unit Urol, Jesi, Italy
[4] Bispebjerg Hosp, Dept Surg, DK-2400 Copenhagen, Denmark
[5] Univ Med Ctr Hamburg Eppendorf, Dept Gen Visceral & Thorac Surg, Hamburg, Germany
[6] Univ Seville, Univ Hosp Virgen del Rocio, Dept Surg, Seville, Spain
[7] Univ London Imperial Coll Sci Technol & Med, Acad Surg Unit, London, England
[8] Klinikum Leverkusen, Dept Gen Visceral & Thorac Surg, Leverkusen, Germany
[9] SJOG Hosp, Dept Surg, Salzburg, Austria