1 Digestive Disease Institute, Cleveland Clinic Abu Dhabi, Cleveland Clinic Lerner College of Medicine, PO Box: 112412, Abu Dhabi, United Arab Emirates.
2 Department of Surgery, Medical University of Vienna, AKH Wien - Leitstelle 21A, Waehringer Guertel 18-20, A-1090, Wien, Austria.
3 King's College Hospital NHS Foundation Trust, Denmark Hill, Brixton, London, SE5 9RS, UK.
4 Humanitas Research Hospital, IRCCS, Via Alessandro Manzoni, 56, 20089, Rozzano, MI, Italy.
5 Department of Surgery, Hospital Clínico San Carlos, Complutense University of Madrid, Calle del Prof Martín Lagos, s/n, 28040, Madrid, Spain.
6 Streamline Clinics Ltd UK, The Sudbury Clinic, Clementine Churchill Hospital, Sudbury Hill, Harrow, HA1 3RX, UK.