Transcutaneous Tibial Neuro-stimulation to Improve Voiding Dysfunction in Multiple Sclerosis.

The present trial is designed to assess the efficacy and safety of transcutaneous tibial neuro-stimulation (TTNS) in improving bladder emptying in multiple sclerosis (MS) patients. Patients presenting with MS and performing clean intermittent self-catheterization (CISC) to empty the bladder in the context of voiding dysfunction, will be eligible. Included patients will be randomly assigned to two distinct arms * PTNS de verum : patients will be treated with transcutaneous tibial neuro-stimulation at a rate of one session of 30 consecutive minutes daily for a period of 12 weeks. * PTNS placebo : Patients will be treated with placebo (i.e. no current) transcutaneous tibial neuro-stimulation for 30 consecutive minutes daily for a period of 12 weeks (same treatment regimen as the experimental group). Efficacy in improving voiding dysfunction will be assessed 12 weeks after randomization using the BVE ratio (Bladder Voiding Efficiency) = Ratio of urine volume / total bladder volume.