A Comparison of Electrical Pudendal Nerve Stimulation and Transvaginal Electrical Stimulation for Urge Incontinence

A Comparison of Electrical Pudendal Nerve Stimulation and Transvaginal Electrical Stimulation for Urge Incontinence

A Comparison of Efficacies of Electrical Pudendal Nerve Stimulation Versus Transvaginal Electrical Stimulation in Treating Urge Incontinence

The purpose of this study is to determine whether electrical pudendal nerve stimulation is more effective than transvaginal electrical stimulation in treating urge urinary incontinence (UUI).

Electrical neuromodulation can be used to treat UUI refractory to medication. Electrical neuromodulation therapies include transvaginal or transanal electrical stimulation (TES), percutaneous tibial nerve stimulation (PTNS), sacral neuromodulation (SNM), and pudendal neuromodulation (PNM). TES is easily applicable but is sometimes intolerable for many patients due to discomfort, mucosal injury, and high-intensity stimulation necessary to obtain acceptable outcome. SNM with the InterStim device differs from TES by its continuous stimulation and close nerve contact. It has a high rate of success, but symptoms appear to recur almost immediately after discontinuation of the stimulation, and at least 20 % of patients initially tested do not respond to a test procedure. Its disadvantages included invasiveness, high cost of treatment, high surgical revision rate, device replacement required when battery runs out, and adverse events. PNM with the Interstim device or the Bion device can be used to treat UUI refractory to SNM, but this therapy also has the disadvantages similar to those of SNM. PTNS with needle electrodes is minimally invasive, demonstrates efficacy, and is easily applicable and well tolerated, but PTNS effects diminish over time after the end of treatment. By combining the advantages of PTNS and PNM and incorporating the technique of deep insertion of long acupuncture needles, the investigators 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). 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 pelvic floor muscle contraction, vaginal pressure and pelvic floor surface electromyogram in our previous study have proved that EPNS can exactly excite PN. The purpose of this study is to compare the efficacies of EPNS versus TES in treating female UUI.

Electrical pudendal nerve stimulation, Transvaginal electrical stimulation, Urge urinary incontinence, Comparative study

At a frequency of 2.0 Hz and a moderate intensity (25~35 mA); 60 minutes three times a week for a total of three weeks

At a current intensity of < 60 mA (in 5% increments from 0 mA to the intensity that is sensed without obvious discomfort) and frequencies of 12.5 to 30 Hz, 45 min three times a week for a total of four weeks.

Four sacral points are selected. The two upper points are located about 1 cm bilateral to the sacrococcygeal joint. On the upper points, a needle of 0.40 Х 100 mm is inserted perpendicularly to a depth of 80 to 90 mm to produce a sensation referred to the urethra or the anus. The locations of the two lower points are about 1 cm bilateral to the tip of the coccyx. On the lower points, a needle of 0.40 Х 100 or 125 mm is inserted obliquely towards the ischiorectal fossa to a depth of 90 to 110 mm to produce a sensation referred to the urethra. After the sensation referred to the above regions is produced, each of two pairs of electrodes from a G6805-2 Multi-Purpose Health Device is connected with the two ipsilaterally inserted needles.

A neuromuscular stimulation therapy system (PHENIX USB 4，Electronic Concept Lignon Innovation, France) is used for TES

Inclusion Criteria: UUI history Positive pad test result Urodynamic study: A decrease in bladder capacity at the first desire for urination; a decrease in maximum bladder capacity; low compliance bladder Exclusion Criteria: UUI that can be relieved by drugs Neurogenic or non-neurogenic UUI Other types of incontinence such as stress incontinence and overflow incontinence

Wang S, Zhang S, Zhao L. Long-term efficacy of electrical pudendal nerve stimulation for urgency-frequency syndrome in women. Int Urogynecol J. 2014 Mar;25(3):397-402. doi: 10.1007/s00192-013-2223-7. Epub 2013 Oct 3.