MAYO-CLINIC LONG-TERM ANALYSIS OF THE FUNCTIONAL DURABILITY OF THE AMS 800 ARTIFICIAL URINARY SPHINCTER - A REVIEW OF 323 CASES

Purpose: We determine the long-term durability of the AMS 800 artific ial urinary sphincter in the correction of severe urinary incontinence , and evaluate mechanical versus nonmechanical failure and reoperation rates before (1983 to 1987) and after (1988 to present) the introduct ion of the narrow backing occlusive cuff design. Materials and Methods : From January 1983 to October 1994 more than 400 patients received an AMS 800 artificial urinary sphincter placed by 1 surgeon and 323, mea n age 60.4 years, met study requirements for review. Mean followup was 68.8 months (range 18 to 153). Only patients with a minimum of 18 mon ths of followup were included in the study. Of the 313 men and 10 wome n in the study group sphincters were placed at the urethra in 272 and at the bladder neck in 51. All patients were followed from surgery to the date of sphincter failure. Etiology of the failures was recorded a nd divided into mechanical versus nonmechanical sphincters placed befo re and after the introduction of the narrow backing cuff. Results: Ove rall, 58 of the 139 patients (42%) in the pre-narrow backing cuff grou p versus 31 of the 184 (17%) in the narrow backing cuff group required a first reoperation. Mechanical failure occurred in 29 cases (21%) wi th the pre-narrow backing and 14 (7.6%) with the narrow backing cuff. Nonmechanical failure developed in 24 cases (17%) with the pre-narrow backing and 17 (9%) with the narrow backing cuff. Ultimately 437 opera tions were required in the 323 patients, of whom 234 (72%) required no further surgical intervention at a mean followup of 68.8 months. Conc lusions: Technological advances in the design and construction of the AMS 800 have dramatically decreased the reoperation and failure rates. These advances and improved surgical techniques provide an excellent long-term solution and increased continence in correctly selected pati ents with urinary incontinence.