Use of peripheral neuromodulation of the S3 region for treatment of detrusor overactivity: A urodynamic-based study

Objectives. To determine the efficacy of peripheral neuromodulation of the S3 region in patients with urgency-frequency syndrome due to an overactive bladder. Methods. Fifteen patients (11 women and 4 men) with urgency-frequency syndr ome, as documented by a voiding chart, were diagnosed with overactive bladd er. Pelvic pain was assessed by a visual analogue scale (VAS). Full urodyna mic workup was performed before and after 12 peripheral stimulations with a 9-V monopolar generator, the so-called Stoller Afferent Nerve Stimulator ( SANS). Follow-up was for a mean (SD) of 10.9 (4 to 15) months. Results. Reduction in pain was achieved in all patients, with a decrease in VAS from a mean (SD) of 7.6 (5 to 10) to 3.1 (1 to 7) (P = 0.00049). Seven patients (46.7%) had a complete response and were considered cured, 3 (20. 0%) showed significant improvement, and 5 (33.3%) were classified as nonres ponders, Urodynamic evidence of bladder instability, evident in all patient s before treatment, was eliminated in 76.9% of patients. In all patients, m ean (SD) total bladder capacity increased significantly from 197 (35 to 349 ) to 252 (78 to 384) mt (P = 0.00795), mean (SD) volume at first bladder se nsation from 95 (16 to 174) to 133 (32 to 214) mt (P = 0.00166), and mean ( SD) bladder volume at normal desire to void from 133 (27 to 217) to 188 (47 to 296) mt (P = 0.00232). In the responding group, the mean (SD) total num bers of voids was reduced from 16.1 (9 to 24) times during the day and 4.4 (2 to 6) times during the night to 8.3 (6 to 10) and 1.4 (1 to 2) times (P = 0.002539), respectively. No complications from treatment were observed. Conclusions, Peripheral neuromodulation of the S3 region can successfully t reat patients with urgency-frequency syndrome due to an overactive bladder, UROLOGY 56: 766-771, 2000, (C) 2000, Elsevier Science Inc.