Early low-frequency stimulation of the pudendal nerve can inhibit detrusor overactivity and delay progress of bladder fibrosis in dogs with spinal cord injuries

Abstract

Objectives: To determine the inhibitory effects of pudendal nerve stimulation (5 Hz) on bladder overactivity at the early stage of spinal cord injury (SCI) in dogs, and to explore the possible effects on delayed progression of bladder fibrosis after SCI. Methods: The study was performed using six dogs with spinal cord transection at the T9-T10 level. Group 1 (three dogs) underwent low-frequency electrical stimulation of the pudendal nerve 1 day after spinal cord transection. Group 2 (three dogs) underwent only spinal cord transection. All dogs underwent urodynamic examination at 1 and 3 months after SCI. The bladders were removed for histological examination of fibrosis at 3 months after SCI. Results: Bladder capacity and compliance were significantly increased (Po0.05) by pudendal nerve stimulation in group 1 when compared with group 2 at 1 and 3 months after SCI. Non-voiding contractions (NVCs) were inhibited in group 1 compared with group 2. Collagen fibers were significantly increased and elastic fibers were significantly decreased (Po0.05) in group 2 when compared with group 1. Conclusion: Early low-frequency pudendal nerve stimulation can inhibit detrusor overactivity (DO), increase bladder capacity and delay the progression of bladder fibrosis.

Effects of early intravesical administration of resiniferatoxin to spinal cord‐injured rats in neurogenic detrusor overactivity

“…Management of SCI‐induced urinary incontinence has always been focused on dealing with a chronic condition rather than attempting to harness its development . Recent studies, however, suggest that early interventions are of clear benefit for SCI patients whether they aim to reduce pain and spasticity or improve bladder function . Accordingly, here we found that early intravesical RTX administration significantly attenuated NDO development, acting in peripheral structures without effects on spinal afferent terminations.…”

“…Altogether, results presented support the benefits of early intravesical administration of RTX to attenuate NDO development. Our data adds to the growing body of evidence that postulates that the anticipation of therapeutic intervention might avoid degradation of bladder function, with a clear positive impact on the SCT patients’ quality of life.…”

“…However, current interventions for urinary incontinence are only introduced once bladder dysfunction is a chronic condition, despite studies suggesting that initiating treatment at earlier time points could prevent bladder dysfunction and other SCI‐induced problems. Indeed, it has been shown that pudendal nerve stimulation and sacral neuromodulation prevents NDO in dogs and humans and early administration of fesoterodine to SCI rats improved bladder function several weeks after spinal lesion . Together, these studies indicate that it is possible to control NDO emergence by early interventions in the initial stages of disease progression.…”

Early Fesoterodine Fumarate Administration Prevents Neurogenic Detrusor Overactivity in a Spinal Cord Transected Rat Model

“…Li et al [6] compared urodynamic parameters measured at 1 and 3 months after T9-T10 surgical SCT in 2 distinct groups of beagle dogs. One group of 3 SCT dogs was subjected to early low-frequency PNS, while the second group of 3 SCT was controls.…”

“…Similarly, after acute supra-sacral SCI, early pudendal nerve stimulation (PNS) and sacral neuromodulation (SNM) have been reported to successfully obviate DO, enhancing the potential of preventive measures against SCI-related DO [6,7]. …”