Pediatric Urology Posterior Urethral Valves: Search for a Diagnostic Reference Standard Tom P. V. M. de Jong, Christian Radmayr, Pieter Dik, Rafal Chrzan, Aart J. Klijn, and Laetitia de Kort, for the Pediatric Urology Club Meeting, Stans, Austria, January 2007 OBJECTIVES To test the agreement among pediatric urologists regarding endoscopic findings concerning posterior urethral valves. METHODS A total of 25 experienced pediatric urologic surgeons observed 11 video fragments of cystoure- throscopy in boys. For most of these boys, a strong suspicion of urethral obstruction had been present; however, some were controls. The video fragments stopped when an incision seemed about to be made using the endoscopic hook on, or behind, 17 folds/valves. The pediatric urologic surgeons were then asked whether they would have incised these folds/valves. The only additional clinical information given was that a suspicion of obstruction was present for most cases and that a few control cases had been included. They could only answer “yes” or “no.” RESULTS Agreement of 80% was observed for 12 of the 17 questions. Of the 17 cases, 5 yielded agreement of 50%-75%. Only in 1 case, was 100% agreement reached. Most surgeons did not regard a flap valve at the 12-o’clock position as an obstruction. The voiding cystourethrograms of several cases with good positive agreement regarding posterior urethral valve obstruction displayed no radiologic suspicion of posterior urethral valves. CONCLUSIONS When judging cystoscopy results, we found fair to good agreement among pediatric urologists regarding whether a urethral obstruction is present. If a urethra appears normal on voiding cystourethrography, this does not exclude the possibility of a urethral obstruction. A true reference standard for urethral obstruction in boys does not seem to exist, and clinical data and additional diagnostic procedures are needed for diagnosis in most cases. UROLOGY 72: 1022–1025, 2008. © 2008 Elsevier Inc. P osterior urethral valves (PUVs) are the most com- mon form of urethral obstruction in boys. 1,2 Cys- toscopy is considered to be the reference standard for determining the presence of a urethral obstruction. It is supposed to be more reliable than voiding cystoure- thrography (VCUG) and even more reliable than urody- namic studies. 3,4 The question of whether a urethral obstruction might be present is of utmost relevance in male infants with a history of pyelonephritis or uni- or bilateral reflux, and in older boys with urge inconti- nence. 5,6 Worldwide, pediatricians are in agreement that if a urethra appears to be normal on VCUG, no urethral obstruction is present, and, therefore, it is not necessary to perform cystoscopy. However, it is generally accepted that other obstructions, such as Cobb’s web, syringoceles, and anterior diverticula, are frequently missed on VCUG. 7-10 Moreover, several studies have demonstrated the unreliability of VCUG in cases of PUVs. However, not many urodynamic studies are available in pediatric practice. 6,11 This study was undertaken to test the endo- scopic procedure as the reference standard for deciding whether PUVs are present. For this purpose, pediatric urologists were asked to write down their judgments based on endoscopic video fragments. MATERIAL AND METHODS A DVD was made of video fragments of endoscopic procedures in boys of varying ages (Videos 1-11). In all but 1, these fragments included endoscopies using both a 25° lens and a 9F or 11F resector with a 5° lens, with the straight resection hook aimed at, or hooked behind, a fold or valve. In total, 17 items were selected. In 5 fragments, the question was “are PUVs present: yes or no?” In 6 other fragments, the questions dealt with the different positions (eg, “Would you incise the flap or valve at the 5-o’clock position or the 12-o’clock flap position?” The patients and indications for endoscopy are listed in Table 1. All video fragments were made by 3 pediatric urologic sur- geons (T.D.J., P.D., and A.K.) using the same endoscopic instruments. All patients were under general anesthesia with an additional caudal or epidural block. The patients’ bladder was filled to capacity at a standard 30-40 cm H 2 O pressure. From the Pediatric Renal Center, Department of Pediatric Urology, University Chil- dren’s Hospital University Medical Center Utrecht, Utrecht, The Netherlands; and Department of Pediatric Urology, Medical University Innsbruck, Innsbruck, Austria Reprint requests: Tom P. V. M. de Jong, M.D., Ph.D., F.E.A.P.U., University Children’s Hospital University Medical Center Utrecht, Lundlaan 8, P.O. Box 85090, Utrecht 3508 AB The Netherlands. E-mail: T.P.V.M.dejong@umcutrecht.nl Submitted: May 12, 2007; accepted (with revisions): April 24, 2008 1022 © 2008 Elsevier Inc. 0090-4295/08/$34.00 All Rights Reserved doi:10.1016/j.urology.2008.04.037