PERIPHERAL NEUROMODULATION USING DIRECT CUTANEOUS EXTERNAL PUDENDAL NERVE STIMULATION MAY IMPROVE NEUROGENIC DETRUSOR UNDERACTIVITY- A CASE REPORT

*Dr. Akmal Hafizah Zamli, Dr. Sumayya Shaharom, Dr. Sharifah Aminah Az Zahrah Md Isa

ABSTRACT

Neurogenic bladder dysfunction ranged from detrusor acontractility, underactivity or over activity, depending on the site of neurologic insult. The urinary sphincter also may be affected, resulting in sphincter loss of activity, underactivity, overactivity or loss of coordination with bladder function. Available evidence suggest the use of peripheral neuromodulation (PNM) using tibial nerve or dorsal penile nerve stimulation as an alternative method of non-invasive option for the management of neurogenic bladder dysfunction refractory to other conservative management. However, the application of PNM using direct cutaneous external pudendal nerve stimulation for neurogenic bladder dysfunction remains unexplored, thus the objective of this study. We report on the application of PNM using cutaneous external pudendal nerve stimulation using a neuromuscular electrical device in a 31 year old man with residual neurogenic bladder dysfunction 4 years following transverse myelitis. Intervention protocol involved placement of four external electrode pads over the perineal region. Stimulation applied with starting magnitude of 15 mA with gradual increased until perianal contraction observed. Duration of stimulation was 1 hour for 3 sessions per week until completion of 12 sessions. Post intervention, he reported subjective and objective improvement in symptoms and improved Part I Kings Quality of Life score. There was also Urodynamic evidence of detrusor contraction at 175 mls infusion with Pdet of 15 cmH20 which was absent pre-intervention. Consistent cough induced detrusor contraction with Pdet ranged between 20 – 40 cmH20 was also evident post-intervention. At voiding phase pre-intervention, he was only able to void few drops of urine with post void residual (PVR) volume of 640 mls. Post intervention, he was able to void 140 mls with PVR of 430 mls. Our findings have demonstrated that PNM using external cutaneous pudendal nerve stimulation may be effective in improving detrusor function in a patient with neurogenic detrusor underactivity.

Keywords: Neurogenic bladder, peripheral neuromodulation, pudendal nerve.