1. Unit of Urology, Fondazione PTV Policlinico Tor Vergata, 00133 Rome, Italy
2. Department of Surgical Sciences, Unit of Urology, University of Rome Tor Vergata, 00133 Rome, Italy
3. Unit of Urology, Clinique Saint-Augustin, 33074 Bordeaux, France
4. University Clinic and Polyclinic of Urology, University Hospital of Halle (Saale), D-06120 Halle, Germany