Percutaneous Stimulation a Potential Incontinence Option

by Warren Grill, senior technical editor

Urinary incontinence is a large unmet medical need with debilitating effects. The condition affects an estimated 13 to 15 million Americans, and almost half of the persons diagnosed with urinary incontinence are affected by urge incontinence. Urge incontinence is the involuntary loss of urine accompanied by the strong desire to void, and is differentiated from stress incontinence. Present treatments including absorbent pads, exercise, and pharmaceuticals, and are not always effective and may cause side effects.

Currently, the only available neurotechnology device to treat urge incontinence is the Medtronic InterStim, which uses an electrode placed in the sacral foramen to stimulate the sacral nerves. Other vendors, including Advanced Neuromodulation Systems, are planning to compete with Medtronic in this market. And Advanced Bionics in Valencia, CA, is testing its BION injectable microstimulator for treatment of urge incontinence.

However, recent research into tibial nerve stimulation points to another potential neurotechnology solution for urinary incontinence. Vera Vandoninck and colleagues reported results from a multiple-center clinical trial in the journal Neurourology and Urodynamics. Their trials suggest that tibial nerve stimulation may be an effective treatment for urge incontinence. Thirty-five patients with urge incontinence were enrolled in a prospective trial in both The Netherlands and Italy. Patients underwent weekly stimulation sessions for 12 weeks and were evaluated at the beginning and end of treatment. Stimulation was delivered to the posterior tibial nerve in the shank using needle electrodes at 20 Hz for 30 minutes per session.

Sixty nine percent of the patients experienced a decrease in the number of incontinent episodes by at least half, and 46 percent of the patients experienced no leakage episodes after treatment. The number of leakage episodes decreased from a median of 5 before treatment to a median of 1 after treatment and the severity of leakage also decreased. Further, mean capacity increased from a median of 119 ml before treatment to a median of 191 ml after treatment. Sixty three percent of the subjects reported success and chose to continue the treatment through a weaning period where the interval between stimulation sessions was increased.

These data suggest that transient electrical stimulation of the tibial nerve can exert long-lasting and powerful reductions in urge incontinence. There were no reported side effects other than pain at the site of stimulation. The mechanisms of this effect are not clear, and the presence of a placebo effect was not controlled in this study.

This approach is not entirely novel, and was the basis for the Percutaneous Stoller Afferent Nerve Stimulation System (PerQ SANS). This technology was invented at the University of Iowa Department of Urology. In 1993, the university’s Technology Innovation Center incubator spun off a commercial firm called Urosurge, Inc., in Coralville, IA to market the product. Urosurge received FDA approval for the device for treatment of urinary incontinence in 2000. However, the company subsequently ceased operations.



site design by shalatdesign |