A prospective, single-blind, randomized crossover trial of sacral vs pudendal nerve stimulation for interstitial cystitis

Objective To compare sacral nerve stimulation (SNS) with pudendal nerve stimulation (PNS) for interstitial cystitis (IC). Patients and Methods Twenty-two patients with well-documented, refractory IC had a tined lead placed at S3 and a second electrode implanted at the pudendal nerve via a posterior approach. In a blinded, randomized design, each lead was tested for 7 days. The best lead was implanted to a pulse generator and patients were followed at 1, 3 and 6 months. Results The time required to place a sacral lead was 27.4 min, and a pudendal lead 19.6 min (P = 0.039). Of the 22 patients, 17 (77%) responded and had a permanent implant placed. PNS was chosen as the better lead in 77% and SNS in 24%. The order in which the lead was stimulated had no effect on the final lead implanted and there was no 'carry-over' effect. The overall reduction in symptoms was 59% for PNS and 44% for SNS (P = 0.05). At 6 months after implantation, voids improved by 41% (PNS) and 33% (SNS), and mean voided volume increased 95% and 21%, respectively; validated IC questionnaires improved markedly and complications were minimal. Conclusion This is the first 'blinded' study of SNS vs PNS for IC. A pudendal lead was implanted successfully in all patients, and most chose PNS as better than SNS; the improvement was sustained over time.