The Indiana Experience With Artificial Urinary Sphincters in Children and Young Adults

Abstract

We reviewed a 22-year single institutional experience with the artificial urinary sphincter in children and adolescents. To our knowledge this report represents the largest series in the world in children.Between 1980 and 2002, 142 patients underwent implantation of an artificial urinary sphincter, of whom 93 males and 41 females with a median age of 10 years (range 3 to 39) were available for analysis. A total of 59 patients initially received an AMS 742/792 (American Medical Systems, Inc., Minnetonka, Minnesota) artificial urinary sphincter, of whom 33 were subsequently changed to an AMS 800, while 75 initially received an AMS 800 model. Sphincter followup was terminated at device removal or at the last documented contact. The etiology of incontinence was neuropathic bladder in 107 cases (80%), the exstrophy/epispadias complex in 21 (16%) and other in 6 (4%). Outcome measures included continence, mechanical complications (leakage, tube kink and pump malfunction), functioning sphincter revisions (change in cuff size, pump repositioning and bulbar cuff placement), surgical complications (erosion, infection and misplacement) and associated surgical procedures. Mean followup of the pre-800 and 800 models was 6.9 (range 0.2 to 21.5) and 7.5 years (range 0.1 to 17.1), respectively. Fisher's exact test, Kaplan-Meier life analysis and the chi-square test were used for statistical analysis.After artificial urinary sphincter placement in the 134 patients continence was achieved in 86%, improved in 4% and not achieved in 10%. Of those with a sphincter in place 92% were continent. In terms of bladder emptying after artificial urinary sphincter insertion 22% of patients voided, 11% voided combined with clean intermittent catheterization, 48% performed clean intermittent catheterization only via the urethra, 16% performed it via a catherizable channel and 3% used urinary diversion. A mechanical complication developed in 38 of the 59 patients (64%) with pre-800 model compared with 33 of the 109 (30%) with the 800 model (p <0.0001). A mechanical complication occurred every 7.6 versus 16 patient-years for the pre-800 versus 800 models (p = 0.0001). Revision was required in 15 of the 59 patients (25%) with a pre-800 model versus 17 of the 109 (16%) with the 800 model (p = 0.103). Revision was performed every 22.7 versus 44.3 patient-years for the pre-800 versus the 800 model (p = 0.023). The artificial urinary sphincter eroded in 11 of the 59 patients (19%) with the pre-800 versus 17 of the 109 (16%) with the 800 model (p = 0.52). Ten patients experienced a total of 12 perforations of the augmented bladder after artificial urinary sphincter implantation. A total of 164 secondary surgical procedures were performed, including 38 of 134 bladder augmentations (28%). A total of 30 sphincters were permanently removed.The artificial urinary sphincter is the only bladder neck procedure that allows spontaneous voiding in the neuropathic population, obviates the need for clean intermittent catheterization and yet is compatible with it when necessary. It is also equally versatile in the 2 genders. Mechanical complications occur but they were dramatically decreased by the modifications of the AMS 800 model. In addition, secondary bladder augmentation was required in 28% of our patients. Lifelong followup is mandatory in all patients with an artificial urinary sphincter.