A comparison of the functional durability of the AMS 800 artificial urinary sphincter between cases with and without an underlying neurogenic aetiology.

Abstract

To compare the efficacy and functional durability of the American Medical Systems 800 (AMS 800) artificial urinary sphincter (AUS) device for patients with neurogenic and non-neurogenic incontinence. From 1985 to 2000, 38 patients underwent implantation of an AMS 800 AUS at our institution. Thirty of these patients had complete records and follow-up data available. The mean follow-up for these two groups of patients was six years. Seventeen devices (57%) were implanted for non-neurogenic indications including incontinence after prostatectomy or hysterectomy. Thirteen devices (43%) were implanted for neurogenic conditions including spina bifida, spinal cord injury or severe pelvic trauma. The primary end point measured was continence. Secondary end points included mechanical and non-mechanical device failure, re-operation and complication rates between the two groups. In the neurogenic group, only two patients (15%) have their original device in situ without revisions. Only three patients (23%) in this group are entirely dry. In contrast, seven patients (41%) in the non-neurogenic group are completely dry with their original device in situ. A further four (23%) are entirely dry after device revision or replacement surgery. The rates of mechanical failure were not statistically different between the two groups. The rate of non-mechanical failure (NMF) was statistically greater in the neurogenic group in comparison to that in the non-neurogenic group (p < 0.05). Insertion of an AMS 800 artificial sphincter remains a durable means of regaining urinary continence. Patients who are incontinent as a result of an underlying neurological deficit should be counselled that they might have a higher risk of non-mechanical device failure, requirement for re-operation and that their overall long-term continence rates may be poor.