1. Department of Pediatric Surgery, UKBB (Universitäts-Kinderspital beider Basel), Spitalstrasse 33, 4031 Basel, Switzerland
2. Department of Advanced Medical and Surgical Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, 80138 Naples, Italy
3. CPEP (Centre for Proctology and Perineology), Ospedali Privati Forlì, 47121 Forlì, Italy
4. Department of Surgical Science, Università degli Studi di Cagliari, 09042 Cagliari, Italy
5. Coloproctology Centre, Clinica del Mediterraneo, 97100 Ragusa, Italy
6. Plastic and Reconstructive Surgery Unit, Multidisciplinary Department of Medical-Surgical and Dental Specialties, Università degli Studi della Campania “Luigi Vanvitelli”, 80138 Naples, Italy
7. Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy
8. A.O. Annunziata, 87100 Cosenza, Italy