Non-invasive Nerve Stimulation for Inhibition of Bladder Incontinence in Spinal Cord Injured Subjects.

Overview

Investigators will test S2-S4 dermatome stimulation with spinal cord injury (SCI) individuals using intermittent catheterization to estimate the clinical impact on bladder capacity and continence. For individuals with SCI using intermittent catheterization, investigators hypothesize that dermatome stimulation will decrease bladder spasm frequency and intensity, and reduce bladder incontinence chronically. The goal of this study is to provide objective evidence for the assertion that dermatome stimulation chronically decreases bladder activity and therefore the unwanted side effects of neurogenic bladder. This project will improve the understanding of the neurophysiology of afferent-mediated neural pathways that affect bladder function, and translate recent advances discovered in animal and human studies into clinical research and treatment. The ability to void safely and effectively by electrical stimulation without cutting sacral nerves or the external urethral sphincter would be a major advance. A socially acceptable, predictable and reliable device for reducing incontinence would be widely used and improve quality of life.

Investigators will test S2-S4 dermatome stimulation with SCI individuals using intermittent catheterization to estimate the clinical impact on bladder capacity and continence. For individuals with SCI using intermittent catheterization, investigators will verify that S2-S4 dermatome stimulation is acutely effective at reducing hyper-reflexive bladder activity during bladder filling. Investigators hypothesize that S2-S4 dermatome stimulation will reduce the number and severity of incontinent episodes, increase bladder capacity, and increase the volume catheterized. By comparing the extended outcomes to the acute laboratory outcomes obtained by ourselves and others, investigators can assess the feasibility of acute urodynamics to identify subjects for implanted devices or future studies. For individuals with SCI using intermittent catheterization, investigators hypothesize that dermatome stimulation will decrease bladder spasm frequency and intensity, and reduce bladder incontinence chronically. The goal of this study is to provide objective evidence for the assertion that dermatome stimulation decreases bladder activity and therefore the unwanted side effects of neurogenic bladder. These experiments will demonstrate the neurophysiologic response of acute stimulation through urodynamic test, and will also provide increased evidence for future clinical trials through proof of lessened bladder pressures - an important cause of vesico-ureteral reflux and renal injury. There is a potentially larger population of persons with incomplete SCI than complete SCI who retain sensation in the pelvis who could gain benefit from dermatome stimulation. To examine the outcomes following incomplete SCI (in persons who retain sensation in the pelvis), investigators will test dermatome stimulation to determine the tolerable and effective electrical stimulation parameters in persons that have some degree of preserved motor or sensory function through the lowest sacral spinal cord segments. Investigators will acutely measure the effects of dermatome stimulation on bladder pressure and hyper-reflexic bladder contractions during bladder filling. Investigators hypothesize that dermatome stimulation will increase bladder capacity at stimulus amplitudes that are acutely tolerable to subjects with incomplete SCI. It will determine the feasibility of a non-invasive screening procedure to identify potential candidates for future device implantation, thereby providing a pathway for translation of the technology to implantation. This project will improve the understanding of the neurophysiology of afferent-mediated neural pathways that affect bladder function, and translate recent advances discovered in animal and human studies into clinical research and treatment. The ability to void safely and effectively by electrical stimulation without cutting sacral nerves or the external urethral sphincter would be a major advance. A socially acceptable, predictable and reliable device for reducing incontinence would be widely used and improve quality of life.