Efficacy of Electrical Pudendal Nerve Stimulation for Patients With Post Prostatectomy Urinary Incontinence

Conservative therapy could be considered a choice of treatment for stress urinary incontinence (SUI) as it seems to have no side effect and causes significant and long-term improvement in symptoms. Pelvic floor muscle training (PFMT) and electrical stimulation are two commonly used forms of conservative treatment for SUI. PFMT improves the structural support of the pelvis. However, many patients have difficulty identifying and isolating their pelvic floor muscles (PFM) and are unable to perform the exercise effectively. Furthermore, patients who can identify the PFM often find that the required daily exercise routine is burdensome. Hence, the primary disadvantage of PFMT is lack of long-term patient compliance. Electrical stimulation (ES) is a non-invasive, passive treatment that produces a muscle contraction. Transanal electrical stimulation (TES) has little side-effect, and the patient compliance is 70-85% in published reports. TES results in PFM contraction by indirect nerve stimulation, mainly by polysynaptic reflex responses. The indirect stimulation and reflexive contraction may be the reason why the effect of electrical stimulation is not as good as that of PFMT when performed correctly. By combining the advantages of PFMT and TES and incorporating the technique of deep insertion of long acupuncture needles, we developed electrical pudendal nerve stimulation (EPNS). 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 (PN) and contract the PFM. 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. Our previous study showed that EPNS had a better therapeutic effect on female SUI as compared with PFMT + TES. Simultaneous records of perineal ultrasonographic PFM contraction, vaginal pressure and pelvic floor surface electromyogram in our previous study have proved that EPNS can exactly excite PN and induce PFM contraction in female SUI patients. However, EPNS has also shown satisfactory effect in male patients with SUI problems. The purpose of this study is to compare the efficacy of EPNS to PFMT + TES in treating male SUI.

Inclusion criteria

• incontinence at 1 month or more after RP
• ≥2 incontinence episodes a week on baseline 7-day bladder diary
• no residual cancer after RP on pathological examination

Exclusion criteria

• the presence of preoperative incontinence
• treatment with anticholinergics
• urinary tract infection or hematuria
• postvoid residual volume>100 mL