Long-term outcome and surgical interventions after sacral neuromodulation implant for lower urinary tract symptoms: 14-year experience at 1 center

Abstract

Purpose: Few reports address the reoperation rate after sacral neuromodulation implants. We report our long-term results and reoperations during our 14-year experience with sacral neuromodulation at our center.

Materials and methods: We retrospectively reviewed the patient database at our center to assess the long-term outcome, incidence and cause of surgical re-intervention after InterStim® sacral neuromodulation implantation for lower urinary tract dysfunction between 1994 and 2008.

Results: A total of 96 sacral neuromodulation devices were implanted in 88 women and 8 men. Indications for implantation were bladder pain syndrome in 47.9% of cases, urgency urinary incontinence in 35.4% and idiopathic urinary retention in 16.7%. The explantation rate was 20.8% and median time to removal was 18.5 months. Reasons for explantation in all subgroups were poor result in 12 patients, painful stimulation in 6 and radiation of stimulation to the leg in 2. Median long-term followup was 50.7 months. The long-term success rate was 87.5%, 84.8% and 73% in patients with idiopathic urinary retention, urgency urinary incontinence and bladder pain syndrome, respectively. Overall 39% of patients needed revision of the sacral neuromodulation implant. The main reason for revision was loss of stimulation in 58.5% of cases. The revision rate decreased with the introduction of the tined lead technique from 50% using lead Model 3092 to 31% using lead Model 3893 (Medtronic, Minneapolis, Minnesota). The battery was changed in 8 patients. Mean battery life was 101.8 months.

Conclusions: Sacral neuromodulation is a minimally invasive procedure with a good long-term outcome. The reoperation rate has improved with advances in surgical technique and equipment.