Electrical neuromodulation in the management of lower urinary tract dysfunction: evidence, experience and future prospects

A prospective study to assess the effectiveness and safety of the BlueWind System in the treatment of patients diagnosed with urgency urinary incontinence

BACKGROUND

Overactive bladder (OAB) affects one in six adults in Europe and the United States and impairs the quality of life of millions of individuals worldwide. When conservative management fails, third-line treatments including tibial neuromodulation (TNM) is often pursued. TNM has traditionally been accomplished percutaneously in clinic.

OBJECTIVE

A minimally invasive implantable device activated by a battery-operated external wearable unit has been developed for the treatment of urgency urinary incontinence (UUI), mitigating the burden of frequent clinic visits and more invasive therapies that are currently commercially available.

METHODS

A prospective, multicenter, single-arm, open-label, pivotal study evaluated the safety and effectiveness of the device in adult females with UUI (i.e., wet OAB) (BlueWind Implantable Tibial Neuromodulation [iTNM] system; IDE number #G200013; NCT03596671). Results with the device were previously published under the name RENOVA iStim, which has been since renamed as the Revi™ System. Approximately 1-month post-implantation of the device, participants delivered therapy at their convenience and completed a 7-day voiding diary before visits 6- and 12-months post-treatment initiation. The primary efficacy and safety endpoints were the proportion of responders to therapy ( ≥ 50% improvement on average number of urgency-related incontinence episodes) and incidence of adverse events from implantation to 12-month post-activation.

RESULTS

A total of 151 participants, mean age 58.8 (SD: 12.5), were implanted; 144 and 140 completed the 6- and 12-month visits, respectively. The participants demonstrated mean baseline of 4.8 UUI/day (SD 2.9) and 10 voids/day (SD 3.3). Six and 12-months post-activation, 76.4% and 78.4% of participants, respectively, were responders to therapy in an intent-to-treat analysis. Of the 139 participants with completed 12-month diaries, 82% were responders, 50% were classified as "dry" (on at least 3 consecutive diary days), and 93.5% of participants reported that their symptoms improved. No implanted participant experienced an SAE related to the procedure or device.

CONCLUSIONS

iTNM, delivered and powered by a patient-controlled external wearable communicating with an implant, demonstrated clinically meaningful and statistically significant improvement in UUI symptoms and a high safety profile. This therapy highlights the value of patient-centric therapy for the treatment of UUI.

Can we improve techniques and patients' selection for nerve stimulation suitable for lower urinary tract dysfunctions? ICI-RS 2023

AIMS

Lower urinary tract dysfunctions (LUTD) are very common and, importantly, affect patients' quality of life (QoL). LUTD can range from urinary retention to urgency incontinence and includes a variety of symptoms. Nerve stimulation (NS) is an accepted widespread treatment with documented success for LUTD and is used widely. The aim of this review is to report the results of the discussion about how to improve the outcomes of NS for LUTD treatment.

METHODS

During its 2023 meeting in Bristol, the International Consultation on Incontinence Research Society discussed a literature review, and there was an expert consensus discussion focused on the emerging awareness of NS suitable for LUTD.

RESULTS

The consensus discussed how to improve techniques and patients' selection in NS, and high-priority research questions were identified.

CONCLUSIONS

Technique improvement, device programming, and patient selection are the goals of the current approach to NS. The conditional nerve stimulation with minimally invasive wireless systems and tailored algorithms hold promise for improving NS for LUTD, particularly for patients with neurogenic bladder who represent the new extended population to be treated.

The Efficiency of Rehabilitation Therapy in Patients Diagnosed with Neurogenic Bladder: A Systematic Review

Considerable research efforts have been directed towards investigating neurogenic bladder dysfunction over the preceding decade. This condition stands as the most prevalent and incapacitating pelvic floor disorder amidst patients afflicted with specific upper motor neuron syndromes, including multiple sclerosis, stroke, and spinal cord injury. The current study aims to bring up-to-date findings on rehabilitation methods for treating neurogenic bladder. The Web of Science database (MEDLINE, PsychINFO, EMBASE, CENTRAL, ISRCTN, and ICTRP) was screened for randomized controlled studies and clinical studies using combinations of keywords including "neurogenic bladder", "stroke", "multiple sclerosis", and "spinal cord injury". The PEDro scale was used to assess the quality of the articles included in this study. After a thorough examination, eleven articles met the criteria for inclusion in our research. The outcome measures showed a variety of forms of electrostimulation that can be combined with or without PFMT. These interventions significantly enhance health-related quality of life, as evidenced by various assessment methods. The physical approach constitutes an effective therapeutic method that can reduce the severity of urinary incontinence.

Case report: Sacral neuromodulation for neurogenic lower urinary tract dysfunction in patient with neuronal intranuclear inclusion disease

Neuronal intranuclear inclusion disease is an uncommon neurodegenerative disorder. The diagnosis of this condition has become more definitive based on current research. However, treatment options remain limited. Neurogenic lower urinary tract dysfunction is one of the prevalent and significant complications, which is the result of its multi-system effects. Here, we present the case of a 48-year-old man diagnosed with neuronal intranuclear inclusion disease based on existing evidence and was complicated by neurogenic lower urinary tract dysfunction. Despite undergoing some medical treatments, his lower urinary tract symptoms, including urinary incontinence, incomplete or intermittent voiding, etc, continued to worsen while upper urinary tract injury developed. Based on careful consideration of the patient's condition and the available findings, we performed an unprecedented sacral neuromodulation on him. Implementation of sacral neuromodulation led to significant improvement in his urination function and alleviate kidney function damage. Our case suggests a potential therapeutic role for sacral neuromodulation in the treatment of neurogenic lower urinary tract dysfunction associated with neuronal intranuclear inclusion disease. Additional research is required to determine the effectiveness of sacral neuromodulation in managing neurogenic lower urinary tract dysfunction caused by various etiologies.

Effects of electroacupuncture on chronic urinary retention after pelvic or lumbosacral tumor resection surgeries: a retrospective cohort study

Background

Chronic urinary retention (CUR) resulting from lower motor neuron lesions (LMNL) is a medical condition secondary to pelvic or lumbosacral tumor resection surgeries. Electroacupuncture (EA) is proved to be effective and safe in treating certain lower urinary tract disorders. However, the clinical benefit and optimal duration of EA treatment for CUR following LMNL remain unknown.

Methods

Using a retrospective cohort design, 20 eligible patients diagnosed with CUR resulting from LMNL secondary to pelvic or lumbosacral tumor resection surgeries were included from March 1, 2017, to June 30, 2020. The patients were treated by EA three times a week for 2 to 12 weeks and followed up for 24 weeks after treatment. The electric stimulators with a 5-Hz continuous wave (5-10 mA intensity) were separately connected to bilateral Ciliao (BL32), bilateral Zhongliao (BL33), and bilateral Huiyang (BL35), and stimulators with a 10-Hz continuous wave (1-2 mA intensity) were connected to bilateral Sanyinjiao (SP6). Current intensity was adjusted according to the patients' individual tolerance. The median follow-up was 32 weeks (range, 26-36 weeks). Responders were defined as patients whose post-void residuals (PVR) reduced by 50% or more from baseline. Adverse event was recorded.

Results

Totally 20 patients [mean (standard deviation) age, 48.1 (15.5) years; 9 men (45.0%); 11 women (55.0%)] were included. Of the 20 patients, 14 (70.0%) had responded to EA treatment and stopped catheterization for achieving satisfactory spontaneous urination (PVR <100 mL without complications), 7 (35.0%) had complete resolution (90-100% reduction in PVR from baseline), and 13 (65.0%) scored 1 (much better) or 2 (moderately better) in the Patient Global Impression of Improvement (PGI-I) assessment. Moreover, 6 (30.0%) patients had responded within 4 weeks of EA treatment. According to Kaplan-Meier survival curve, we found that more than 50% patients could respond to EA treatment within 8 weeks or longer. None of the responders had ever experienced relapse in 24 weeks after EA treatment ended. None of the patients manifested urinary tract infection (UTI), newly diagnosed hydroureter or hydronephrosis. One patient diagnosed with hydronephrosis at baseline recovered after 12-week EA treatment. Two patients with UTI at baseline were prescribed antibiotics and did not present UTI again during the follow-up.

Conclusions

EA could be a promising treatment option for CUR caused by LMNL following pelvic or lumbosacral tumor resection surgeries, with long-term effects and a good safety profile. The optimal duration of EA should be of 8 weeks at least. But this was a retrospective cohort study of a small sample size, so future studies are needed to investigate EA in larger populations in randomized controlled trials.

Mechanism of Action of Tibial Nerve Stimulation in the Treatment of Lower Urinary Tract Dysfunction

BACKGROUND AND OBJECTIVE

Tibial nerve stimulation (TNS) has long been used to effectively treat lower urinary tract dysfunction (LUTD). Although numerous studies have concentrated on TNS, its mechanism of action remains elusive. This review aimed to concentrate on the mechanism of action of TNS against LUTD.

MATERIALS AND METHODS

A literature search was performed in PubMed on October 31, 2022. In this study, we introduced the application of TNS for LUTD, summarized different methods used in exploring the mechanism of TNS, and discussed the next direction to investigate the mechanism of TNS.

RESULTS AND CONCLUSIONS

In this review, 97 studies, including clinical studies, animal experiments, and reviews, were used. TNS is an effective treatment for LUTD. The study of its mechanisms primarily concentrated on the central nervous system, tibial nerve pathway, receptors, and TNS frequency. More advanced equipment will be used in human experiments to investigate the central mechanism, and diverse animal experiments will be performed to explore the peripheral mechanism and parameters of TNS in the future.

Brain Response Induced by Peroneal Electrical Transcutaneous Neuromodulation Invented for Overactive Bladder Treatment, as Detected by Functional Magnetic Resonance Imaging

OBJECTIVES

In this study, we aimed to investigate whether peroneal electrical Transcutaneous Neuromodulation invented for overactive bladder (OAB) treatment elicits activation in brain regions involved in neural regulation of the lower urinary tract.

MATERIALS AND METHODS

Among 22 enrolled healthy female volunteers, 13 were eligible for the final analysis. Functional magnetic resonance imaging (fMRI) (Siemens VIDA 3T; Erlangen, Germany) was used to compare the brain region activation elicited by peroneal electrical Transcutaneous Neuromodulation with the activation elicited by sham stimulation. Each subject underwent brain fMRI recording during eight 30-second periods of rest, alternating with 30-second periods of passive feet movement using the sham device, mimicking the motor response to peroneal nerve stimulation. Subsequently, fMRI recording was performed during the analogic "off-on" stimulation paradigm using peroneal electrical transcutaneous neuromodulation. Magnetic resonance imaging data acquired during both paradigms were compared using individual and group statistics.

RESULTS

During both peroneal electrical Transcutaneous Neuromodulation and sham feet movements, we observed activation of the primary motor cortex and supplementary motor area, corresponding to the cortical projection of lower limb movement. During peroneal electrical Transcutaneous Neuromodulation, we observed significant activations in the brain stem, cerebellum, cingulate gyrus, putamen, operculum, and anterior insula, which were not observed during the sham feet movement.

CONCLUSIONS

Our study provides evidence that peroneal electrical Transcutaneous Neuromodulation elicits activation of brain structures that have been previously implicated in the perception of bladder fullness and that play a role in the ability to cope with urinary urgency. Our data suggest that neuromodulation at the level of supraspinal control of the lower urinary tract may contribute to the treatment effect of peroneal electrical Transcutaneous Neuromodulation in patients with OAB.

Implantable Multi-Cross-Linked Membrane-Ionogel Assembly for Reversible Non-Faradaic Neurostimulation

Neural interfaces play a major role in modulating neural signals for therapeutic purposes. To meet the demand of conformable neural interfaces for developing bioelectronic medicine, recent studies have focused on the performance of electrical neurostimulators employing soft conductors such as conducting polymers and electronic or ionic conductive hydrogels. However, faradaic charge injection at the interface of the electrode and nerve tissue causes irreversible gas evolution, oxidation of electrodes, and reduction of biological ions, thus causing undesired tissue damage and electrode degradation. Here we report a conformable neural interface engineering based on multicross-linked membrane-ionogel assembly (termed McMiA), which enables nonfaradaic neurostimulation without irreversible charge transfer reaction. The McMiA consists of a genipin-cross-linked biopolymeric ionogel coupled with a dopamine-cross-linked graphene oxide membrane to prevent ion exchange between biological and synthetic McMiA ions and to function as a bioadhesive forming covalent bonds with the target tissues. In addition, the demonstration of bioelectronic medicine via the McMiA-based neurostimulation of sciatic nerves shows the enhanced clinical utility in treating the overactive bladder syndrome. As the McMiA-based neural interface is soft, robust for bioadhesion, and stable in a physiological environment, it can offer significant advancement in biocompatibility and long-term operability for neural interface engineering.

Efficacy of Transcutaneous Tibial Nerve Stimulation With Silver Spike Point® Electrodes for Refractory Overactive Bladder: A Single-Arm Study

Background Tibial nerve stimulation therapy is a treatment option for an overactive bladder. A surface electrode called a Silver Spike Point® electrode, which does not directly puncture the skin as in transcutaneous tibial nerve stimulation, but is expected to exert the same therapeutic effect as percutaneous tibial nerve stimulation, was developed. This study investigated the efficacy and safety of tibial nerve stimulation with Silver Spike Point® electrodes for refractory overactive bladder. Methodology This was a six-week, single-arm, prospective study on the efficacy and safety of transcutaneous tibial nerve stimulation for patients with refractory overactive bladder. Each treatment lasted 30 minutes and was performed twice a week. The stimulation sites of the tibial nerve were the Sanyinjiao point (SP6) and Zhaohai point (KI6) in both legs. The primary endpoint was the change in the total overactive bladder symptom score. Results In total, 29 patients (20 males and nine females: 64.86 ± 17.98 years old) were included in this study. Two women dropped out; one because of an adverse event and the other as requested. Therefore, 27 patients completed the study. The total overactive bladder symptom and International Consultation on Incontinence Questionnaire-Short Form scores significantly decreased by 2.22 and 2.39 points, respectively (p < 0.01 each). In the frequency volume chart, the numbers of urgency episodes and leaks in 24 hours significantly decreased by 1.53 and 0.44, respectively (p = 0.02 each). Conclusions Transcutaneous tibial nerve stimulation therapy using Silver Spike Point® electrodes was useful for patients with refractory overactive bladder and, thus, has potential as a new treatment option for refractory overactive bladder.

The translational implications of the science behind the overactive bladder and the role of OnabotulinumtoxinA

Urinary incontinence (UI) is a very common condition that can affect patients of all ages and the commonest cause is an overactive bladder (OAB). Most patients with OAB were treated with pharmacotherapy and major surgery. Over 25 years ago, Dasgupta, Fowler et al. studied the presence and role of C fibres in the human bladder which are highly sensitive to capsaicin, the active ingredient of chillies. When capsaicin was instilled into patients' bladders as a synthetic solution, it was found to be highly effective in some patients. Capsaicin was later replaced by Resiniferatoxin. Both toxins desensitised C-fibres through the capsaicin receptor, TRPV1, without any lasting damage to the bladder itself. The discovery of botulinum toxin and its use in the treatment of OAB represents a major breakthrough, in the treatment of OAB. Another key innovation was the development of technique to administer the drug under local anaesthesia which allowed numerous patients to benefit from treatment who would otherwise have been precluded because of the need for injection under general anaesthetic. After extensive trials over many years Botox (OnabotulinumtoxinA) is now licensed for use in OAB. Compared to other treatments for overactive bladder, OnabotulinumtoxinA is more cost-effective and less invasive. It is thought to have changed the quality of life of an estimated 5 million patients worldwide.

Comparison of the efficacy and safety of sacral root magnetic stimulation with transcutaneous posterior tibial nerve stimulation in the treatment of neurogenic detrusor overactivity: an exploratory randomized controlled trial

Background

Both repetitive sacral root magnetic stimulation (rSMS) and transcutaneous posterior tibial nerve stimulation (TTNS) have demonstrated clinical benefits for lower urinary tract dysfunction. However it still remains unclear that which method is more effective and safer to treat neurogenic detrusor overactivity (NDO).

Methods

From December 2020 to December 2021, 50 patients (31 men and 19 women, aged 47.9±12.4 years) with NDO secondary to suprasacral spinal cord injury (SCI) were enrolled and randomly allocated to the rSMS or TTNS group based on a computer-generated random numbers table. The stimulation was applied continuously 5 times per week for 20 sessions. Urodynamic test was conducted at baseline and the day after the final 20th treatment session. The primary outcome was the individual change (Δ) in maximum cystometric capacity (MCC) from baseline to post-treatment. Secondary outcomes included changes (Δ) for the following parameters: volume at 1st involuntary detrusor contraction (1st IDCV), maximal detrusor pressure (Pdetmax), bladder compliance (BC), postvoid residual (PVR) volume, and bladder voiding efficiency (BVE). Additionally, adverse reactions including pain and skin irritation during stimulation were observed and recorded as safety outcomes.

Results

Finally 47 patients completed the study (23 in rSMS and 24 in TTNS group). A per-protocol (PP) analysis was performed, and Mann-Whitney U test and unpaired t-test were used for statistical analysis. Compared with the efficacy of TTNS, rSMS showed statistically greater ΔMCC [median +43 mL (IQR, 22–62 mL) vs. +20 mL (IQR, 15–25 mL), P=0.001, with a between-group difference of +22 mL (95% CI: +7 to +35 mL)] and ΔBVE [median +10.0% (IQR, 3.8–15.7%) vs. +3.5% (IQR, 0.0–7.8%), P=0.003, with a between-group difference of +5.9% (95% CI: +1.2% to +9.7%)]. No significant differences were found in Δ1st IDCV (P=0.40), ΔPdetmax (P=0.67), ΔBC (P=0.79) and ΔPVR (P=0.92) between the two groups. Meanwhile, patients exhibited high tolerance to both protocols, and no adverse reactions were observed.

Conclusions

RSMS may be more effective to improve urodynamics in the treatment for NDO than TTNS, cause it led to a statistical improvement in bladder capacity and voiding efficiency, without any side effects. RSMS is thus worthy of further clinical promotion.

Trial Registration

Chinese Clinical Trial Registry ChiCTR2100050663.

Peroneal Electrical Transcutaneous NeuroModulation as a New Treatment for Patients with Overactive Bladder: An Initial Clinical Experience

INTRODUCTION

The aim of this study was to determine whether peroneal electrical Transcutaneous NeuroModulation (peroneal eTNM®) using the URIS® neuromodulation system can be used in individuals with refractory overactive bladder (OAB).

METHODS

Eighteen female patients with idiopathic OAB who failed previous behavioral and pharmacological therapy were enrolled. Patients were treated with the URIS® neuromodulation system using active electrodes placed on the popliteal fossa, targeting the peroneal nerve for 30 min once a week for 12 weeks. Changes in OAB symptoms and patient-reported outcomes from baseline to the end of the study were analyzed. A nonparametric Wilcoxon signed-rank test was used to assess changes in variables. Statistical significance was defined as p ≤ 0.05.

RESULTS

We observed a significant reduction in micturition frequency (p = 0.022), number of severe urgency episodes (p < 0.001), urgency incontinence episodes (p = 0.001), and nocturia episodes (p = 0.027). A decrease in Patient Perception of Bladder Condition score (p < 0.001) was also observed. Posttreatment, 15 patients (83.3%) reported a moderate or significant reduction in their bladder bother. Throughout the study, two adverse events were recorded with no causal relationship to the study treatment.

DISCUSSION/CONCLUSIONS

Our study documented a significant reduction in all OAB symptoms and an improvement in all patient-reported outcomes in patients treated with peroneal eTNM® using the URIS® neuromodulation system.

Posterior Tibial Nerve Stimulation for Overactive Bladder: Mechanism, Classification, and Management Outlines

Purpose of the Review. Posterior tibial nerve stimulation (PTNS) techniques have dramatically grown after approval to manage overactive bladder (OAB). The present review will focus on the most current data on PTNS types (percutaneous, transcutaneous, and implant) and their mechanism of action, safety, efficacy, advantages, drawbacks, limitation, and clinical applications. Recent Findings. The present review described the recent studies that addressed the tibial nerve stimulation role in OAB management. BlueWind RENOVA system, Bioness StimRouter, and eCoin are examples of emerging technologies that have evolved from interval sessions (percutaneous PTNS and transcutaneous PTNS) to continuous stimulation (implants). These can be efficiently managed at home by patients with minimum burden on the health system and fewer visits, especially in the COVID-19 pandemic. Summary. Our review shows that the tibial nerve stimulation advancements in OAB treatment have been rapidly increasing over the recent years. It is minimally invasive and effective, similar to sacral nerve stimulation (SNM), but less aggressive. Implantable PTNS has been promised in terms of efficacy, safety, and high acceptance rate. However, evidence is still limited to short-term trials, and tolerability, method, and drawbacks remain challenges.

Maternal and foetal physiological response of sacral surface electrical stimulation during pregnancy: a preliminary study

NEW FINDINGS

What is the central question of this study? The physiological response to sacral neuromodulation by pregnant women and foetuses has not been previously explored. What is the main finding and its importance?

ABSTRACT

This study aimed to examine the impact of sacral surface electrical stimulation on maternal and foetal physiology during pregnancy. Ten pregnant women at 36 weeks of gestation without multiple gestations, foetuses with malformations, foetal growth restriction, hypertensive disorders, polyhydramnios, or oligohydramnios were enrolled. This prospective study monitored maternal and foetal physiological responses before and after sacral surface electrical stimulation for single pregnancies. Sacral surface electrical stimulation was performed once per patient. Each parameter was measured directly before and then immediately after stimulation. Follow-up measurements were conducted at 12 h, 1 day, 2 days and 7 days after stimulation. Variables of interest were compared before and after the stimulation. Regarding the foetal Doppler measurements, significant differences were not found in the umbilical and middle cerebral artery pulsatility index. However, foetuses showed a significant increase in the umbilical venous flow volume. The uterine contraction frequency and the maternal uterine artery pulsatility index significantly decreased. Pregnancy outcomes, and rates of caesarean section, foetal distress, and neonatal asphyxia were not confirmed. In conclusion, sacral surface electrical stimulation had no adverse effects on pregnant women or foetuses at 36 weeks of gestation and might improve utero-placental perfusion and lower back pain. This article is protected by copyright. All rights reserved.

[Transcutaneous stimulation of the posterior tibial nerve modifies the sympathetic skin response and improves overactive bladder syndrome: Case series and possible diagnostic test]

OBJECTIVE

(a) To assess the effect of transcutaneous neuromodulation (TNM) of the posterior tibial nerve plus biofeedback on the sympathetic skin response (SSR). (b) Evaluate its effect on clinical symptoms. (c) Consider SSR as a probable neurophysiological test useful both for diagnosis and for follow-up in patients with overactive bladder (OAB). (d) Evaluate its cost compared to other techniques.

MATERIAL AND METHODS

A prospective quasi-experimental before and after study in 10 OAB patients.

OUTCOME VARIABLES

daytime (DUF) and nighttime (NUF) urinary frequency, strength of the pelvic floor muscles measured by manometry (maximum and mean pressure) and sympathetic skin response (SSR).

RESULTS

DUF improved from 10.3±5.45 to 5.9±2.42 episodes (P=.0050). The NUF improved from 2.4±1.5 to 0.6±0.69 episodes (P=.0012). The maximum pressure ranged from 34.7±16.51 to 39.7±3.65mmHg (P=.0195). The mean pressure of the pelvic floor muscles improved from 6.6±3.65 to 9.3±5.43mmHg (P=.0333). SSR changed from 100% hyperexcitability prior to treatment to 50±14.14% (P=.0000).

CONCLUSION

TNM plus biofeedback could modify SSR and improve clinical and manometry variables in a series of patients with OAB. The probable diagnostic and prognostic utility of this neurophysiological test in OAB and detrusor hyperactivity is reported for the first time. A larger sample study is needed to confirm the promising findings seen in this preliminary study.

Effectiveness of acupuncture for nocturia: A protocol for systematic review and meta-analysis

BACKGROUND

Nocturia is a common and highly troubled lower urinary tract symptom, which has a wide range of effects. About 33% of patients with lower urinary tract symptoms have been affected by nocturia. Nocturia is mainly manifested as the increase of urination frequency and urine volume at night. It has been proved that acupuncture can reduce the symptoms of nocturia and regulate bladder function in Western countries. Acupuncture may be a promising choice for the treatment of nocturia.

METHODS

RCTs of acupuncture for nocturia will be searched in the relevant database, including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure Wanfang Database, Chinese Biomedical Literature Database, and Chinese Scientific Journal Database. The studies of electronic searches will be exported to EndNote V.9.1 software. We will run meta-analyses using the Review Manager (RevMan) V.5.3 software. Any disagreement will be solved in consultation with a third reviewer.

RESULTS

Our study aims to explore the efficacy of acupuncture for nocturia and to provide up-to-date evidence for clinical of nocturia.

CONCLUSION

The conclusion of this study will provide evidence for the efficacy of acupuncture treatment of nocturia.

INPLASY REGISTRATION NUMBER

INPLASY202130100.

Fowler's Syndrome-The Cause of Urinary Retention in Young Women, Often Forgotten, but Significant and Challenging to Treat

Urinary retention in young women is a relatively rare clinical problem and is often underdiagnosed. In particular, functional causes of urinary retention pose a diagnostic challenge. One of them is Fowler's syndrome, which is associated with impaired urethral relaxation. Fowler's syndrome is characterized by a large bladder capacity, reduced sensation, increased maximal urethral closure pressure, and detrusor underactivity. Several hypotheses have arisen to explain the cause of urethral relaxation disorders: hormonal changes characteristic of Polycystic Ovary Syndrome (PCOS), causing abnormal stabilization of the muscle membrane, primary failure of relaxation of the striated muscle of the urethra sphincter, and increased urethral afferent activity, inhibiting the bladder afferent signals from reaching the brain by potentiating a spinal mechanism of urinary continence. Currently, sacral neuromodulation is the only intervention that can restore an atypical voiding pattern in women with Fowler's syndrome. The therapeutic effectiveness exceeds 70%, although the revision rate is relatively high, exceeding 50%. Well-designed, long-term prospective studies comparing sacral neuromodulation (SNM) with other therapies such as pelvic floor muscle physiotherapy are warranted to offer the best patient-tailored treatment.

Long-term Outcomes of Sacral Nerve Stimulation in Pelvic Floor Dysfunctions

Purpose

The aim of this study was to analyze the long-term outcomes of sacral nerve stimulation (SNS) in both idiopathic and neurogenic pelvic floor disorders in patients treated at a referral center.

Methods

This retrospective observational study analyzed the records of 106 patients tested at our department from December 1999 to January 2017. The efficacy variables evaluated were the Global Response Assessment (range, 0%–100%) and, according to the clinical indication, other specific variables such International Consultation on Incontinence QuestionnaireShort Form, number of catheterizations or pads/day, and the numerical pain scale. The safety variables analyzed were complications (pain, migration, infection), reinterventions and explants. Patients’ quality of life (QoL) and satisfaction with the procedure were evaluated through telephone interviews.

Results

The clinical indications were overactive bladder (OAB) (n=36), urinary retention (UR) (n=37), bladder pain syndrome/interstitial cystitis (BPS/IC) (n=19), fecal incontinence (FI) (n=8), and double incontinence (DI) (n=6). The implant rates according to the clinical indication were as follows: OAB, 55.6%; UR, 56.8%; BPS/IC, 63.15%; FI, 87.5%; and DI, 66.7%. Clinical and/or statistically significant improvements in all efficacy variables were observed. Loss of therapeutic effect at 75 months of follow-up was observed in 34% of patients. Device-related pain appeared in 25 patients (39%); in 20 patients, it was resolved by reprogramming and 5 patients required device removal. An overall improvement in QoL and high levels of satisfaction with the procedure were observed. More than 90% of patients would recommend SNS to a friend or relative.

Conclusions

SNS is a minimally invasive procedure that offers a real alternative to patients with refractory pelvic floor dysfunction. Its safety profile is very favorable and it provides a long-lasting improvement in symptoms and QoL.

Randomised Crossover-Controlled Evaluation of Simultaneous-Bilateral Transcutaneous Electrostimulation of the Posterior Tibial Nerve During Urodynamic Studies on Patients With Lower Urinary Tract Symptoms

Purpose

Transcutaneous tibial nerve stimulation (TTNS) has proven to be a valuable treatment option for various lower urinary tract conditions, such as overactive bladder syndrome and neurogenic detrusor overactivity. The aim of this study was to investigate acute changes in urodynamic parameters due to bilateral TTNS.

Methods

Fifty-one patients (18–87 years; 61% female) with various lower urinary tract symptoms were enrolled in this study. They were single-blinded and randomly assigned to receive simultaneous bilateral TTNS either during their first urodynamic examination, followed by a second round using a placebo stimulation technique, or vice versa.

Results

For subjects without signs of anatomical pathologies, the filling volume at the first desire to void (FDV) increased significantly by 54 mL (interquartile range [IQR], 26–81 mL; P<0.01) under the influence of TTNS compared to placebo. The maximum cystometric capacity increased by 41 mL (IQR, 10–65 mL; P=0.02). The median micturition volume of patients with pathological postvoid residual volumes (>100 mL) increased by 76 mL compared to patients without urinary retention (IQR, 6–166 mL; P=0.03).

Conclusions

Compared to placebo, simultaneous bilateral TTNS showed significant improvements in bladder functioning, such as delayed FDV, increased maximum cystometric capacity, and reduced urinary retention. Patients with signs of anatomical pathologies did not seem to benefit from TTNS. Further studies need to be conducted to compare the effectiveness of bilateral versus unilateral TTNS.

Ameliorating effects of sacral neuromodulation on gastric and small intestinal dysmotility mediated via a sacral afferent-vagal efferent pathway

BACKGROUND/AIMS

In a recent study of sacral nerve stimulation (SNS) for colonic inflammation, a possible spinal-vagal pathway was implicated. The aim of this study was to provide evidence for such a pathway by investigating the effects of SNS on dysmotility of the stomach and duodenum that are not directly innervated by the sacral efferents.

METHODS

Twenty-seven rats were chronically implanted with wire electrodes for SNS and gastrointestinal slow waves. SNS was performed in several acute sessions to investigate its effects on gastric/duodenal slow waves and emptying/transit impaired by glucagon and rectal distention (RD).

RESULTS

(a) SNS increased the percentage of normal gastric slow waves impaired by glucagon (from 53.9% to 77.0%, P < .0001) and RD (from 64% to 78%, P = .037). This improvement was abolished by atropine. (b) Similar effects were observed with SNS on duodenal slow waves, which was also blocked by atropine. (c) SNS normalized delayed gastric emptying induced by glucagon (control: 61.3%, glucagon: 44.3%, glucagon + SNS: 65.8%) and RD (control: 61.3%, RD: 46.7%, RD + SNS: 64.3%). It also normalized small intestinal transit delayed by RD (P = .001, RD + SNS vs RD; P = .9, RD + SNS vs control). (4) Both glucagon and RD induced an increase in the sympathovagal ratio (P = .007, glucagon vs baseline; P < .001, RD vs baseline) and SNS decreased the ratio (P = .006, glucagon + SNS vs glucagon; P = .04, RD + SNS vs RD).

CONCLUSIONS

Neuromodulation of the sacral nerve improves gastric and small intestinal pacemaking activity and transit impaired by glucagon and RD by normalizing the sympathovagal balance via a retrograde neural pathway from the sacral nerve to vagal efferents.

Functional segregation within the pelvic nerve of male rats: a meso- and microscopic analysis

The pelvic splanchnic nerves are essential for pelvic organ function and have been proposed as targets for neuromodulation. We have focused on the rodent homologue of these nerves, the pelvic nerves. Our goal was to define within the pelvic nerve the projections of organ-specific sensory axons labelled by microinjection of neural tracer (cholera toxin, subunit B) into the bladder, urethra or rectum. We also examined the location of peptidergic sensory axons within the pelvic nerves to determine whether they aggregated separately from sacral preganglionic and paravertebral sympathetic postganglionic axons travelling in the same nerve. To address these aims, microscopy was performed on the major pelvic ganglion (MPG) with attached pelvic nerves, microdissected from young adult male Sprague-Dawley rats (6-8 weeks old) and processed as whole mounts for fluorescence immunohistochemistry. The pelvic nerves were typically composed of five discrete fascicles. Each fascicle contained peptidergic sensory, cholinergic preganglionic and noradrenergic postganglionic axons. Sensory axons innervating the lower urinary tract (LUT) consistently projected in specific fascicles within the pelvic nerves, whereas sensory axons innervating the rectum projected in a complementary group of fascicles. These discrete aggregations of organ-specific sensory projections could be followed along the full length of the pelvic nerves. From the junction of the pelvic nerve with the MPG, sensory axons immunoreactive for calcitonin gene-related peptide (CGRP) showed several distinct patterns of projection: some projected directly to the cavernous nerve, others projected directly across the surface of the MPG to the accessory nerves and a third class entered the MPG, encircling specific cholinergic neurons projecting to the LUT. A subpopulation of preganglionic inputs to noradrenergic MPG neurons also showed CGRP immunoreactivity. Together, these studies reveal new molecular and structural features of the pelvic nerves and suggest functional targets of sensory nerves in the MPG. These anatomical data will facilitate the design of experimental bioengineering strategies to specifically modulate each axon class.

New Implantable Tibial Nerve Stimulation Devices: Review of Published Clinical Results in Comparison to Established Neuromodulation Devices

Purpose

The purpose of this review is to offer an update for medical providers practicing general urology and urogynecology in evolving and new promising technologies for neuromodulation in patients with OAB.

Patients and Methods

A focused literature search for the years 2015 through 2019 was conducted on PubMed/Medline for the terms: “new techniques” AND “neuromodulation” AND “tibial nerve stimulation” AND “overactive bladder”. We limited our search to publications in English, for the last five years and with patient follow-up of at least 3 months.

Results

Clinical success, safety based on adverse events, and quality of life improvement criteria were evaluated and compared to sacral nerve stimulation (SNS) devices and older, non-implantable percutaneous tibial nerve stimulation (PTNS) treatment devices. Considering the limited number of participants with up to 6 months follow-up data currently available, overall the clinical response rates suggest that the new implantable devices stimulating the tibial nerve have a promising clinical outlook, are less invasive upon implantation than SNS, less expensive, and less of a burden on patients compared to the older non-implantable PTNS devices.

Conclusion

Practicing urologists should be aware of this new treatment option when counseling their patients regarding treatment for OAB.

Outcomes of Intradetrusor Onabotulinum Toxin A Therapy in Overactive Bladder Refractory to Sacral Neuromodulation

Purpose

Intradetrusor onabotulinum toxin A (BTXA) and sacral neuromodulation (SNM) are effective third-line therapies for overactive bladder (OAB). We aimed to measure the outcomes of BTXA for treatment of OAB refractory to initial SNM and identify patient characteristics associated with these outcomes.

Methods

This retrospective cohort study included patients who failed to respond to initial SNM treatment for OAB and subsequently received BTXA at a single provider’s clinic between January 2013 and December 2016. Treatment successes were defined as patients willing to continue BTXA or who found symptom relief whereas treatment failures discontinued BTXA due to adverse effects or lack of symptom relief. Symptoms and patient-reported outcomes on validated questionnaires were compared before the initial BTXA trial to 2 months after the last BTXA treatment. The SNM failure BTXA groups were also compared to BTXA SNM naïve groups.

Results

Of 18 patients who received BTXA after failed SNM treatment, 7 (39%) achieved treatment success. Successfully treated patients demonstrated decreased urinary frequency from a median 11 voids/day pre-BTXA to 8 voids/day with BTXA (P=0.042). Patients whose treatment failed reported increased complaints of a weak urinary stream (P=0.03) and higher frequency of straining to urinate (P=0.016) than the successful treatment group pre-BTXA. Compared to BTXA patients without prior SNM, the odds of failing BTXA after initial SNM were 3.6 times higher (P=0.016).

Conclusions

BTXA appears effective for OAB refractory to SNM, although the success rate is lower compared to BTXA patients without SNM exposure.

What Is New in Neuromodulation?

Neuromodulation encompassing sacral and peripheral modalities is an established, effective, and safe higher-order treatment option approved in the USA for managing refractory overactive bladder, non-obstructive urinary retention, and fecal incontinence. This review highlights the most recent literature, indications, treatment durability, and the latest innovations in this field. Regarding sacral neuromodulation (SNM), recent work suggests improved parameters for optimal lead placement, increased data to support the lasting effects of treatment, and novel applications of this technology to other pelvic disorders. In addition, there are emerging technologies with smaller MRI compatible devices. Newer data on percutaneous tibial nerve stimulation (PTNS) suggests it may be more beneficial for certain patients. With new technology, implantable tibial nerve stimulators are ushering in a new frontier of nerve stimulation in the comfort of the patient's home.

[Sacral neuromodulation in under- and overactive detrusor-quo vadis? : Principles and developments]

BACKGROUND

Sacral neuromodulation (SNM) has been used in the treatment of refractory overactive bladder syndrome, nonobstructive urinary retention and faecal incontinence for almost 40 years now. It is not to be confused with the sacral anterior root stimulation which is exclusively used for bladder dysfunction due to spinal paraplegia.

MECHANISM OF ACTION

The principles of SNM are yet to be fully understood. Nevertheless, there is proof of modulating the activity of several micturition-associated, afferent neurons in the spine, brainstem and cerebrum. Thus, premature detrusor contractions are suppressed, the desire to void is delayed and detrusor-sphincter coordination improves.

TECHNIQUES OF IMPLANTATION AND STIMULATION

Motor reactions are an important indicator of correct electrode placement. The implantation procedure consists of two stages with an initial trial phase to determine the best possible treatment response through an external generator before implanting the whole stimulating device. Yearly check-up examinations are recommended; wireless adjustments allow for long-lasting symptom reduction.

INDICATION AND OUTCOME

Success rates in the treatment of the refractory overactive bladder syndrome and the non-obstructive urinary retention lie above 70% and can still be perceived as sufficient after 5 years of ongoing SNM therapy. There is also profound evidence of SNM being an effective option for patients with faecal incontinence or chronic obstipation.

CONTRAINDICATIONS AND RISKS

Children, pregnant women and patients in need of frequent MRI examinations are usually not eligible for SNM therapy. Infection of the implant, technical failure (including lead displacement and battery depletion) and pain in the implantation site are important adverse effects which might require surgical revision.

CONCLUSIONS

The indications for SNM in the German health care system can be expected to be expanded upon the chronic pelvic pain syndrome, erectile dysfunction and additional gastrointestinal conditions. Technical progress will continue to improve the risk-benefit ratio of SNM.

Neuromodulation - a therapeutic option for refractory overactive bladder. A recent literature review

Overactive bladder (OAB) affects approximately 17% of the population. The treatment of this clinical condition is challenging, especially when conservative therapy is not effective. There are limited options for the treatment of recurrent OAB. Neuromodulation has taken a significant place in the therapy of recalcitrant lower urinary tract dysfunctions over the past 20 years. The aim of this study was to review the literature evaluating the different forms of neuromodulation in various urological clinical conditions and to show the future prospects of this treatment method. Further studies are necessary to determine the effectiveness of neuromodulation and to identify the prognostic factors of therapeutic success. This could be helpful in the selection of patients who will be most likely to respond positively to the treatment.

Suppression of Urinary Voiding "on Demand" by High-Frequency Stimulation of the S1 Sacral Nerve Root in Anesthetized Rats

OBJECTIVES

High-frequency (kHz) stimulation of preganglionic pelvic nerve afferents can inhibit voiding in both anesthetized and conscious rats. The afferents travel via the S1 sacral nerve root, which is easier to access than the distal pelvic nerve fibers within the abdominal cavity. We therefore investigated whether voiding could be inhibited by high-frequency stimulation at S1 and how this compared to distal pelvic nerve stimulation.

METHODS

Urethane-anesthetized rats were instrumented to record bladder pressure and abdominal wall electromyogram and to stimulate the distal preganglionic pelvic nerve bundle and S1 sacral root. Saline was infused continuously into the bladder to evoke repeated voiding. Stimulation was initiated within 1-2 sec of the onset of the steep rise in bladder pressure signaling an imminent void.

RESULTS

In six rats, stimulation of the distal pelvic nerve bundle (1-3 kHz sinusoidal waveform 1 mA, 60 sec) supressed the occurrence of an imminent void. Voiding resumed within 70 ± 13.0 sec (mean ± SEM) of stopping stimulation. Stimulation (using the same parameters) of the S1 root at the level of the sacral foramen suppressed voiding for the entire stimulation period in three rats and deferred voiding for 35-56 sec (mean 44.0 ± 3.2 sec) in the remaining three. Stimulation at either site when the bladder was approximately half full, as estimated from previous intervoid intervals, had no effect on voiding.

CONCLUSIONS

This preliminary study provides proof-of-concept for the sacral root as an accessible target for high-frequency stimulation that may be developed as an "on demand" neuromodulation paradigm to suppress unwanted urinary voids.

CONFLICT OF INTEREST

The authors reported no conflict of interest.

Detecting Bladder Biomarkers for Closed-Loop Neuromodulation: A Technological Review

Neuromodulation was introduced for patients with poor outcomes from the existing traditional treatment approaches. It is well-established as an alternative, novel treatment option for voiding dysfunction. The current system of neuromodulation uses an open-loop system that only delivers continuous stimulation without considering the patient's state changes. Though the conventional open-loop system has shown positive clinical results, it can cause problems such as decreased efficacy over time due to neural habituation, higher risk of tissue damage, and lower battery life. Therefore, there is a need for a closed-loop system to overcome the disadvantages of existing systems. The closed-loop neuromodulation includes a system to monitor and stimulate micturition reflex pathways from the lower urinary tract, as well as the central nervous system. In this paper, we reviewed the current technological status to measure biomarker for closed-loop neuromodulation systems for voiding dysfunction.

The anatomy of urination: What every physician should know

Normal voiding needs a coordinated, sustained bladder contraction of adequate size and duration. It requires a decrease in resistance of the bladder neck and urethra and no obstruction. Voiding problems can arise from abnormal storage of urine or problems with urinary control. The aim of this article was to review the functional anatomy and physiology of urinary control and micturition and the pathophysiology of urinary control problems. The Medline (PubMed) database, Cochrane Library, and Science Citation Index were searched electronically to identify original published studies on bladder anatomy, function and urinary control. References were searched from relevant chapters in specialized texts and all were included. Voiding problems are the most common presenting urological symptoms in general medical practice. Urinary incontinence occurs when the normal process of storing and passing urine is disrupted. A history of coexisting fecal incontinence suggests a neuropathic etiology. A better understanding of the physiology of urinary control could lead to preventive measures for postoperative urinary retention and incontinence such as fluid restriction and to appropriate anesthesia/analgesia, autonomic nerve preservation, total mesorectal excision (TME) for rectal cancer, and biofeedback exercises. It could also suggest appropriate therapeutic measures for established urinary incontinence. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.

Neuromodulation for Pelvic and Urogenital Pain

Chronic pain affecting the pelvic and urogenital area is a major clinical problem with heterogeneous etiology, affecting both male and female patients and severely compromising quality of life. In cases where pharmacotherapy is ineffective, neuromodulation is proving to be a potential avenue to enhance analgesic outcomes. However, clinicians who frequently see patients with pelvic pain are not traditionally trained in a range of neuromodulation techniques. The aim of this overview is to describe major types of pelvic and urogenital pain syndromes and the neuromodulation approaches that have been trialed, including peripheral nerve stimulation, dorsal root ganglion stimulation, spinal cord stimulation, and brain stimulation techniques. Our conclusion is that neuromodulation, particularly of the peripheral nerves, may provide benefits for patients with pelvic pain. However, larger prospective randomized studies with carefully selected patient groups are required to establish efficacy and determine which patients are likely to achieve the best outcomes.

Urology as rehabilitation medicine: a literature review

As a urologist, we usually encounter with two representative functional behaviors, namely, voiding and sexual function. These are not only important but also complex and synchronized so if these functions are impaired, patients need active functional rehabilitation to recover. These functional impairments should be recognized and corrected early because they could not only cause direct damage to the affected functions but also have harmful consecutive consequences such as kidney damage due to voiding abnormality and self-esteem damage due to decreased sexual function. Numerous rehabilitative methods are currently available, which help minimize the negative effects of these functional impairments. In terms of voiding function, pelvic floor muscle exercise, biofeedback, functional magnetic stimulation, neuromodulation, and clean intermittent self-catheterization are representative rehabilitation modalities. In case of children, extra-attention should be paid because this might affect their entire life. In impairment of sexual function, early intervention to maintain male erection is the main target of rehabilitation to prevent corporal fibrosis and penile deformity and increase recovery chance in patients who underwent radical prostatectomy or major surgery. In this review, we will elucidate various rehabilitation methods in urology to further increase our understanding of the rehabilitative characteristics of urology and widen our view of rehabilitation medicine.