De Gennaro M1, Di Ciommo V2, Capitanucci M L3, Mosiello G1, Orazi C 4, Schingo P5, Adorisio O6, Tubaro A7 1. Bambino Gesu' Children's Hospital, Dept Nephro-Urology, Urodynamic Unit , 2. Bambino Gesu' Children Hospital, Epidemiology and Statistics Unit, 3. Bambino Gesu' Children's Hospital, Dept of Nephro-Urology, 4. Bambino Gesu' Children's Hospital, Deptof Radiology, 5. Bambino Gesu' Children's Hospital, Dept of Radiology, 6. Mayer Children's Hospital, Pediatric Surgery Unit, 7. Urology Dept "La Sapienza" University of Rome