The purpose of this study is to compare the efficacy of electrical pudendal nerve stimulation (EPNS) and Tolterodine Tartrate in patients with urgency-frequency syndrome.

Tolterodine Tartrate is one of the first-line medications in treatment of Urgency-frequency syndrome (UFS) patients. It is reported to reduce frequency urgency and nocturia and urinary leakage in patients with UFS. However dry mouth and constipation are the most frequently reported adverse events. In other reports blurred vision and increased heart rate are also reported. The side effects limit its application.

Electrical neuromodulation has proved to be valuable in patients with UFS with little adverse effect. The investigators have previously reported electrical pudendal nerve stimulation (EPNS) alone has long term effect in treatment of UFS in women patients. EPNS is developed by combining the advantages of pudendal nerve stimulation (PNS) and percutaneous tibial nerve stimulation (PTNS), and incorporating the technique of deep insertion of long acupuncture needles. Because pudendal nerve (PN) afferents are particularly important for the inhibitory effect on the voiding reflex and SNS only excites part of PN afferents, direct PN stimulation may be more effective. PNS can be used to treat UFS refractory to SNS, but this therapy also has the disadvantages similar to those of SNS. PTNS is minimally invasive, demonstrates efficacy, and is easily applicable and well tolerated, but the results of chronic PTNS treatment are unknown in initially successful patients and PTNS effects diminish over time.

In EPNS, long acupuncture needles of 0.40 Х 100 or 125 mm were deeply inserted into four sacral points and electrified to stimulate the pudendal nerves. CT transverse plane at the coccygeal apex has showed that the position of the lower needle tip is similar to where (adjacent to PN at Alcock's canal) the Bion device is implanted for chronic PN stimulation. Besides the radiographic evidence, simultaneous records of perineal ultrasonographic PFM contraction, vaginal pressure and pelvic floor surface electromyogram in the investigators previous study have proved that EPNS can exactly excite PN. The investigators previous study has also proved that EPNS has a good post-treatment effect on UFS in women. The purpose of the present study is to show the long-term efficacy of EPNS for UFS in women.

Inclusion Criteria:

• Urgency with a documented daytime frequency of more than eight voids and/or nocturia of more than one void.

Exclusion Criteria:

• Age <18 years,or >80 years;
• Urinary tract infections based on results of urinalysis or urine culture;
• Painful bladder syndrome manifested by suprapubic pain related to bladder filling accompanied by frequency and other diseases (including interstitial cystitis, neurogenic bladder, bladder tumor, and vesical calculus)
• Causative of urgency and frequency confirmed by physical examination, B-scan ultrasonography.

urodynamic study, cystoscopy, and radiography