Pudendal nerve stimulation appears effective in neurogenic OAB

Pudendal nerve stimulation, using a pudendal percutaneous implant under neurophysiologic guidance, appears effective in treating neurogenic overactive bladder, Italian researchers reported Thursday.

The average number of urinary incontinence episodes decreased from seven to 2.6 during the study`s screening phase in patients receiving chronic pudendal nerve stimulation, said Michele Spinelli, MD, a physician in the spinal unit at Niguarda Hospital in Milan, Twenty-nine patients with urge incontinence became continent during the screening phase.

The implant procedure is done under local anesthesia and allows researchers to check responses of sacral area dysfunctions. Subjects included 14 men and 22 women (mean age, 35 years). All patients in the study were neurogenic and presented with a variety of conditions, including spina bifida, transverse myelitis, and vascular myelopathy.

Twenty of the 36 subjects first underwent invasive sacral neuromodulation staged implant with tined lead (SNM), while 16 patients underwent chronic pudendal nerve stimulation using the same system. Of the 20 who first underwent SNM, nine had worsening symptoms, and 11 had no success at all. Patients completed neurophysiologic and urodynamic evaluation at baseline and at follow-up. They completed a bowel and voiding diary for 7 days.

At follow-up of 21 months, 17 were dry using self-catheterization for voiding, two patients used catheterization twice a day, and 15 voided without a catheter.

"The procedure has not only an effect on bladder function, but also on erection and bowel function," Dr. Spinelli noted. "If you stimulate this target [the sacrum], it has an effect on other areas."

Seven males reported an increase in mean International Index Erectile Function score from 32% to 79%, consequently reducing their use of oral drugs for erection. Researchers plan a larger study involving multiple centers to confirm their results.