Dorsal genital nerve stimulation in patients with detrusor overactivity: a systematic review

Minimally Invasive Two-passage Electrical Genital Nerve Stimulation: A Human Cadaver Study of a New Technique

STUDY OBJECTIVE

To present and evaluate the feasibility of a new technique of lead-electrode stimulation to the genital nerves using a 2-step, double-passage retropubic/retrograde approach.

DESIGN

Prospective observational study.

INTERVENTIONS

The procedure was initiated in the retropubic passage by placing the electrode from below through a paravulvar/testicular small incision toward the urogenital diaphragm, guided through the retropubic space along the backside of the pubic bone. Through a second passage along the frontside of the pubic bone, the lead-electrode was placed finally at the genital nerves.

SETTING

Department of Anatomy, University Bern, Bern, Switzerland PARTICIPANTS: The study was performed in 5 cadavers (bilaterally) and tested by 10 obstetrics and gynecology surgeons.

MEASUREMENTS AND MAIN RESULTS

Positions and courses of the lead electrode in relation to the dorsal nerve of the clitoris/penis were evaluated by dissection of the genitals and showed an optimal parallel course of the lead electrodes to the dorsal nerve from the perforation of the urogenital diaphragm to the crura of the clitoris, with area of the dorsal nerve of the clitoris/penis to the electrode never exceeding 2 mm. Participant surgeons self-evaluated reproducibility and difficulty of the procedure by using a score from 1 to 10 (1, easy/safe; 10, extremely difficult/dangerous). Both reproducibility and difficulty achieved a score of 1 by all participants.

CONCLUSIONS

The double-passage genital nerve stimulation procedure is a new peripheral nerve stimulation technique that had a high self-evaluated rate of ease and reproducibility for surgeon participants.

Update on the management of overactive bladder

Overactive bladder (OAB) syndrome is a common condition characterised by urinary urgency, with or without urgency incontinence, frequency and nocturia, in the absence of any other pathology. Clinical diagnosis is based upon patient self-reported symptomology. Currently there is a plethora of treatments available for the management of OAB. Clinical guidelines suggest treatment via a multidisciplinary pathway including behavioural therapy and pharmacotherapy, which can be commenced in primary care, with referral to specialist services in those patients refractory to these treatments. Intradetrusor botulinum A and sacral neuromodulation provide safe and efficacious management of refractory OAB. Percutaneous tibial nerve stimulation and augmentation cystoplasty remain available and efficacious in a select group of patients. Unfortunately, there remains a high rate of patient dissatisfaction and discontinuation in all treatments and thus there remains a need for emerging therapies in the management of OAB.

Neuropelveology: An Emerging Discipline for the Management of Pelvic Neuropathies and Bladder Dysfunctions through to Spinal Cord Injury, Anti-Ageing and the Mars Mission

Neuropelveology is a new specialty in medicine that has yet to prove itself but the need for it is obvious. This specialty includes the diagnosis and treatment of pathologies and dysfunctions of the pelvic nerves. It encompasses knowledge that is for the most part already known but scattered throughout various other specialties; neuropelveology gathers all this knowledge together. Since the establishment of the International Society of Neuropelveology, this discipline is experiencing an ever-growing interest. In this manuscript, the author gives an overview of the different aspects of neuropelveology from the management of pelvic neuropathic pain to pelvic nerves stimulation for the control of pelvic organ dysfunctions and loss of functions in people with spinal cord injuries. The latter therapeutic option opens up new treatments but also widens preventive horizons not only in the field of curative medicine (osteoporosis and cardio-vascular diseases) but also in preventive medicine and anti-ageing, all the way to future applications in the "Mars mission" project.

At-home genital nerve stimulation for individuals with SCI and neurogenic detrusor overactivity: A pilot feasibility study

OBJECTIVE

Neurogenic bladder dysfunction, including neurogenic detrusor overactivity (NDO) is one of the most clinically significant problems for persons with spinal cord injury (SCI), affecting health and quality of life. Genital nerve stimulation (GNS) can acutely inhibit NDO-related reflex bladder contractions and increase bladder capacity. However, it is unknown if GNS can improve urinary continence or help meet individuals' bladder management goals during sustained use, which is required for GNS to be clinically effective.

DESIGN

Subjects maintained voiding diaries during a one-month control period without stimulation, one month with at-home GNS, and one month after GNS. Urodynamics and quality of life assessments were conducted after each treatment period, and a satisfaction survey was taken at study completion.

SETTING

Subject screening and clinical procedures were conducted at the Louis Stokes Cleveland VA Medical Center. Stimulation use and voiding diary entries were conducted in subjects' homes.

PARTICIPANTS

Subjects included five men with SCI and NDO.

INTERVENTIONS

This study tested one month of at-home portable non-invasive GNS.

OUTCOME MEASURES

The primary outcome measure was leakage events per day. Secondary outcome measures included self-reported subject satisfaction, bladder capacity, and stimulator use frequency.

RESULTS

GNS reduced the number of leakage events from 1.0 ± 0.5 to 0.1 ± 0.4 leaks per day in the four subjects who reported incontinence data. All study participants were satisfied that GNS met their bladder goals; wanted to continue using GNS; and would recommend it to others.

CONCLUSIONS

Short term at-home GNS reduced urinary incontinence and helped subjects meet their bladder management goals. These data inform the design of a long-term clinical trial testing of GNS as an approach to reduce NDO.

Genital nerve stimulation increases bladder capacity after SCI: A meta-analysis

BACKGROUND

Neurogenic detrusor overactivity (NDO) often results in decreased bladder capacity, urinary incontinence, and vesico-ureteral reflux. NDO can trigger autonomic dysreflexia and can impair quality of life. Electrical stimulation of the genital nerves (GNS) acutely inhibits reflex bladder contractions and can increase bladder capacity. Quantifying the effect of GNS on bladder capacity and determining what study factors and subject factors influence bladder capacity improvements will inform the design of clinical GNS interventions.

METHODS

We measured bladder capacity in 33 individuals with NDO, with and without GNS. These data were combined with data from seven previous GNS studies (n=64 subjects). A meta-analysis of the increase in bladder capacity and potential experimental factors was conducted (n=97 subjects total).

RESULTS

Bladder capacity increased 131±101 ml with GNS across subjects in all studies. The number of individuals whose bladder capacity was greater than 300 ml increased from 24% to 62% with GNS. Stimulus amplitude was a significant factor predicting bladder capacity gain. The variance of the bladder capacity gain significantly increased with increasing infusion rate. Other factors did not contribute to bladder capacity gain.

CONCLUSION

GNS acutely increases bladder capacity in individuals with NDO. The consistent increase in magnitude of bladder capacities across the eight studies, and the lack of dependence on individual-specific factors, provide confidence that GNS could be an effective tool for many individuals with NDO. Studies of the chronic effect of GNS on bladder control, with clinical measures such as urinary continence, are needed.

Stimulation of the sensory pudendal nerve increases bladder capacity in the rat

Pudendal nerve stimulation is a promising treatment approach for lower urinary tract dysfunction, including symptoms of overactive bladder. Despite some promising clinical studies, there remain many unknowns as to how best to stimulate the pudendal nerve to maximize therapeutic efficacy. We quantified changes in bladder capacity and voiding efficiency during single-fill cystometry in response to electrical stimulation of the sensory branch of the pudendal nerve in urethane-anesthetized female Wistar rats. Increases in bladder capacity were dependent on both stimulation amplitude and rate. Stimulation that produced increases in bladder capacity also led to reductions in voiding efficiency. Also, there was a stimulation carryover effect, and increases in bladder capacity persisted during several nonstimulated trials following stimulated trials. Intravesically administered PGE₂ reduced bladder capacity, producing a model of overactive bladder (OAB), and sensory pudendal nerve stimulation again increased bladder capacity but also reduced voiding efficiency. This study serves as a basis for future studies that seek to maximize the therapeutic efficacy of sensory pudendal nerve stimulation for the symptoms of OAB.

Clinical utility of neurostimulation devices in the treatment of overactive bladder: current perspectives

Objectives

This review describes the evidence from established and experimental therapies that use electrical nerve stimulation to treat lower urinary tract dysfunction.

Methods

Clinical studies on established treatments such as percutaneous posterior tibial nerve stimulation (P-PTNS), transcutaneous electrical nerve stimulation (TENS), sacral nerve stimulation (SNS) and sacral anterior root stimulation (SARS) are evaluated. In addition, clinical evidence from experimental therapies such as dorsal genital nerve (DGN) stimulation, pudendal nerve stimulation, magnetic nerve stimulation and ankle implants for tibial nerve stimulation are evaluated.

Results

SNS and P-PTNS have been investigated with high-quality studies that have shown proven efficacy for the treatment for overactive bladder (OAB). SARS has proven evidence-based efficacy in spinal cord patients and increases the quality of life. TENS seems inferior to other OAB treatments such as SNS and P-PTNS but is noninvasive and applicable for ambulant therapy. Results from studies on experimental therapies such as pudendal nerve stimulation seem promising but need larger study cohorts to prove efficacy.

Conclusion

Neurostimulation therapies have proven efficacy for bladder dysfunction in patients who are refractory to other therapies.

Significance

Refinement of neurostimulation therapies is possible. The aim should be to make the treatments less invasive, more durable and more effective for the treatment of lower urinary tract dysfunction.

Overactive bladder - 18 years - Part I

Abstract: Overactive bladder syndrome is one of the lower urinary tract dysfunctions with the highest number of scientific publications over the past two decades. This shows the growing interest in better understanding this syndrome, which gathers symptoms of urinary urgency and increased daytime and nighttime voiding frequency, with or without urinary incontinence and results in a negative impact on the quality of life of approximately one out of six individuals – including both genders and almost all age groups. The possibility of establishing the diagnosis just from clinical data made patients' access to specialized care easier. Physiotherapy resources have been incorporated into the urological daily practice. A number of more selective antimuscarinic drugs with consequent lower adverse event rates were released. Recently, a new class of oral drugs, beta-adrenergic agonists has become part of the armamentarium for Overactive Bladder. Botulinum toxin injections in the bladder and sacral neuromodulation are routine modalities of treatment for refractory cases. During the 1st Latin-American Consultation on Overactive Bladder, a comprehensive review of the literature related to the evolution of the concept, epidemiology, diagnosis, and management was conducted. This text corresponds to the first part of the review Overactive Bladder 18-years.

Subject-Controlled, On-demand, Dorsal Genital Nerve Stimulation to Treat Urgency Urinary Incontinence; a Pilot

OBJECTIVES

To evaluate the effect of subject-controlled, on-demand, dorsal genital nerve (DGN) stimulation on non-neurogenic urgency urinary incontinence (UUI) in a domestic setting.

MATERIALS AND METHODS

Non-neurogenic patients >18 years with overactive bladder symptoms and UUI were included. Exclusion criteria were mainly stress urinary incontinence. Patients underwent 1 week of subject-controlled, on-demand, DGN stimulation, delivered by a percutaneously placed electrode near the DGN connected to an external stimulator (pulse-rate 20 Hz, pulse-width 300 μs). Patients activated the stimulator when feeling the urge to void and stimulated for 30 s. The amplitude was set at the highest tolerable level. A bladder diary including a severity score of the UUI episodes/void (scores: 0 = none, 1 = drops, 2 = dashes, 3 = soaks) and a padtest was kept 3 days prior to, during, and 3 days after the test period. The subjective improvement was also scored.

RESULTS

Seven patients (4 males/3 females) were enrolled, the mean age was 55 years (range 23-73). Six completed the test week. In the remaining patient the electrode migrated and was removed. 5/6 finalized the complete bladder diary, 1/6 recorded only the heavy incontinence episodes (score = 3). 4/6 completed the padtest. In all patients who finalized the bladder diary the number of UUI episodes decreased, in 3/5 with ≥60%. The heavy incontinence episodes (score = 3) were resolved in 2/6 patients, and improved ≥80% in the other 4. The severity score of the UUI episodes/void was improved with ≥ 60% in 3/5 patients. The mean subjective improvement was 73%.

CONCLUSION

This feasibility study indicates that subject-controlled, on-demand DGN stimulation using a percutaneously placed electrode is possible over a longer time period, in a home setting, with a positive effect on non-neurogenic overactive bladder symptoms with UUI. Although the placement is an easy procedure, it is difficult to fixate the electrode to keep it in the correct position. Improvements in hardware, like a better fixated electrode and an easy to control stimulator, are necessary to make SODGNS a treatment possibility in the future.

Functional electrical stimulation and spinal cord injury

Spinal cord injuries (SCI) can disrupt communications between the brain and the body, resulting in loss of control over otherwise intact neuromuscular systems. Functional electrical stimulation (FES) of the central and peripheral nervous system can use these intact neuromuscular systems to provide therapeutic exercise options to allow functional restoration and to manage medical complications following SCI. The use of FES for the restoration of muscular and organ functions may significantly decrease the morbidity and mortality following SCI. Many FES devices are commercially available and should be considered as part of the lifelong rehabilitation care plan for all eligible persons with SCI.

The role of electrical stimulation techniques in the management of the male patient with urgency incontinence

PURPOSE OF REVIEW

Overactive bladder affects 10-27% of men, a significant portion of whom report urge urinary incontinence that is inadequately treated with first-line and second-line treatments. There is thus a substantial need to critically evaluate the alternative means of clinical management.

RECENT FINDINGS

This review presents the current evidence for the use of sacral neuromodulation and percutaneous tibial nerve stimulation in the treatment of men with urge incontinence, as well as evaluates the financial implications of these treatments. Other alternative modes of electrical stimulation for urge incontinence are also briefly reviewed.

SUMMARY

Both sacral neuromodulation and percutaneous tibial nerve stimulation prove to be viable, durable options for treating patients with refractory urge incontinence. Alternative modes of stimulation are also beginning to show promise.

Penile vibratory stimulation in the recovery of urinary continence and erectile function after nerve-sparing radical prostatectomy: a randomized, controlled trial

OBJECTIVE

To examine the effect of penile vibratory stimulation (PVS) in the preservation and restoration of erectile function and urinary continence in conjunction with nerve-sparing radical prostatectomy (RP).

PATIENTS AND METHODS

The present study was conducted between July 2010 and March 2013 as a randomized prospective trial at two university hospitals. Eligible participants were continent men with an International Index of Erectile Function-5 (IIEF-5) score of at least 18, scheduled to undergo nerve-sparing RP. Patients were randomized to a PVS group or a control group. Patients in the PVS group were instructed in using a PVS device (FERTI CARE(®) vibrator). Stimulation was performed at the frenulum once daily by the patients in their own homes for at least 1 week before surgery. After catheter removal, daily PVS was re-initiated for a period of 6 weeks. Participants were evaluated at 3, 6 and 12 months after surgery with the IIEF-5 questionnaire and questions regarding urinary bother. Patients using up to one pad daily for security reasons only were considered continent. The study was registered at http://clinicaltrials.gov/ (NCT01067261).

RESULTS

Data from 68 patients were available for analyses (30 patients randomized to PVS and 38 patients randomized to the control group). The IIEF-5 score was highest in the PVS group at all time points after surgery with a median score of 18 vs 7.5 in the control group at 12 months (P = 0.09), but the difference only reached borderline significance. At 12 months, 16/30 (53%) patients in the PVS group had reached an IIEF-5 score of at least 18, while this was the case for 12/38 (32%) patients in the control group (P = 0.07). There were no significant differences in the proportions of continent patients between groups at 3, 6 or 12 months. At 12 months 90% of the PVS patients were continent, while 94.7% of the control patients were continent (P = 0.46).

CONCLUSION

The present study did not document a significant effect of PVS. However, the method proved to be acceptable for most patients and there was a trend towards better erectile function with PVS. More studies are needed to explore this possible effect further.