Transcutaneous Electrical Nerve Stimulation for Treating Neurogenic Lower Urinary Tract Dysfunction: A Systematic Review

Research and progress on the mechanism of lower urinary tract neuromodulation: a literature review

The storage and periodic voiding of urine in the lower urinary tract are regulated by a complex neural control system that includes the brain, spinal cord, and peripheral autonomic ganglia. Investigating the neuromodulation mechanisms of the lower urinary tract helps to deepen our understanding of urine storage and voiding processes, reveal the mechanisms underlying lower urinary tract dysfunction, and provide new strategies and insights for the treatment and management of related diseases. However, the current understanding of the neuromodulation mechanisms of the lower urinary tract is still limited, and further research methods are needed to elucidate its mechanisms and potential pathological mechanisms. This article provides an overview of the research progress in the functional study of the lower urinary tract system, as well as the key neural regulatory mechanisms during the micturition process. In addition, the commonly used research methods for studying the regulatory mechanisms of the lower urinary tract and the methods for evaluating lower urinary tract function in rodents are discussed. Finally, the latest advances and prospects of artificial intelligence in the research of neuromodulation mechanisms of the lower urinary tract are discussed. This includes the potential roles of machine learning in the diagnosis of lower urinary tract diseases and intelligent-assisted surgical systems, as well as the application of data mining and pattern recognition techniques in advancing lower urinary tract research. Our aim is to provide researchers with novel strategies and insights for the treatment and management of lower urinary tract dysfunction by conducting in-depth research and gaining a comprehensive understanding of the latest advancements in the neural regulation mechanisms of the lower urinary tract.

[Invasive neurostimulation in neuro-urology: state of the art]

Modulation or stimulation of the nerves supplying the lower urinary tract is a possible treatment option for dysfunction of the lower urinary tract, pelvic floor and rectum if conservative or minimally invasive treatment approaches fail. This overview shows the possibilities and limitations of sacral neuromodulation, sacral deafferentation with sacral anterior root stimulation and conus deafferentation.Sacral neuromodulation (SNM) is a procedure for the treatment of refractory pelvic floor dysfunction of various origins (idiopathic, neurogenic or post-operative), such as overactive bladder, non-obstructive retention and faecal incontinence. A particular advantage of SNM is the possibility of prior test stimulation with a high prognostic value. The procedure is minimally invasive, reversible and associated with relatively low morbidity rates.Following the introduction of MRI-compatible SNM systems, there has been renewed interest in the treatment of neurogenic bladder dysfunction. A recent meta-analysis reports similar success rates as in the idiopathic patient population.Sacral deafferentation with implantation of a sacral anterior root stimulator (SARS/SDAF) is an excellent therapeutic option for patients with spinal cord injury, which can significantly improve the quality of life of those affected and, in addition to treating neurogenic lower urinary tract dysfunction, can also have a positive effect on neurogenic bowel dysfunction, neurogenic sexual dysfunction or autonomic dysreflexia. If conservative or minimally invasive treatment fails, it is crucial for the success of this procedure to consider SDAF/SARS at an early stage in order to avoid irreversible organic damage.Conus deafferentation (KDAF) is a less invasive surgical treatment option for patients with spinal cord injury for whom sacral deafferentation would be indicated but who would not benefit from the simultaneous implantation of a sacral anterior root stimulator. In principle, these patients also have the option of being subsequently treated with an extradural implant and thus utilising the advantages of anterior root stimulation. Indications for KDAF are autonomic dysreflexia, therapy-refractory detrusor overactivity, recurrent urinary tract infections, urinary incontinence and spasticity triggered by detrusor overactivity. With KDAF, we have a safe and efficient procedure with great potential for improving the spectrum of paraplegiological and neuro-urological treatment.

Transcutaneous Electrical Stimulation for Neurogenic Bladder After Spinal Cord Injury: A Systematic Review and Meta-Analysis

OBJECTIVES

This review aims to assess the efficacy of transcutaneous electrical nerve stimulation (TENS) for neurogenic bladder after spinal cord injury (SCI).

MATERIALS AND METHODS

A systematic search was conducted of seven electronic data bases from inception to Dec 31, 2022, to identify randomized controlled trials that studied TENS for neurogenic bladder after SCI. The primary outcomes were maximum cystometric capacity (MCC) and residual urine volume (RUV). Secondary outcomes included maximum detrusor pressure, flow rate, and bladder diary. Random effects models were used in all analyses.

RESULTS

Eleven trials involving 881 participants were included. Meta-analysis showed that TENS in addition to conventional treatment had larger MCC (mean difference [MD] 50.55 ml, 95% CI 27.81-73.29, p＜0.0001) and lower RUV (MD -22.96 ml, 95% CI -33.45 to -12.47, p＜0.0001) than did conventional treatment only. Compared with magnetic stimulation, no differences were observed with TENS for MCC (MD -14.49 ml, 95% CI -48.97 to 19.98, p = 0.41) and RUV (MD 25 ml, 95% CI -61.79 to 111.79, p = 0.57). There also were no differences in MCC (MD -7.2 ml, 95% CI -14.56 to 0.16, p= 0.06) and (MD -5.2 ml, 95% CI -60.00 to 49.60, p = 0.851) when compared with solifenacin succinate and pelvic floor biofeedback, respectively.

CONCLUSIONS

TENS may be an effective treatment option for neurogenic bladder after SCI.

Aging with spinal cord injury: A narrative review of consequences and challenges

Given the increase in life expectancy, aging with a pre-existing spinal cord injury (SCI) is becoming more common. This condition is challenging as compromised health status and functional independence can worsen. We aimed to provide an updated overview of the consequences of aging with SCI, highlighting the main challenges facing this population in a narrative review of the current literature we retrieved from the PubMed database from 2000 to 2022 on any aspect related to aging in persons with SCI. Here we address adverse circumstances that increase disability and hinder an active lifestyle, such as progressive physical deterioration, secondary health conditions, limitations in personal activity, changes in family and social support structures, aging of caregivers, and depletion of economic resources. Favorable changes are also observed, including psychosocial adjustments that improve quality of life. Additionally, various interventions are discussed to promote well-being, health, and social participation. Due to the relevance of this issue, people with SCI and all those who take care of them must have up-to-date information to carry out the necessary measures to promote healthy aging in a more inclusive social environment.

bTUNED: transcutaneous tibial nerve stimulation for neurogenic lower urinary tract dysfunction

OBJECTIVE

To present the protocol for a randomized controlled trial (RCT) evaluating the efficacy and safety of transcutaneous tibial nerve stimulation (TTNS) for refractory neurogenic lower urinary tract dysfunction (NLUTD).

STUDY DESIGN AND RESULTS

bTUNED (bladder and TranscUtaneous tibial Nerve stimulation for nEurogenic lower urinary tract Dysfunction) is an international multicentre, sham-controlled, double-blind RCT investigating the efficacy and safety of TTNS. The primary outcome is success of TTNS, defined as improvements in key bladder diary variables at study end compared to baseline values. The focus of the treatment is defined by the Self-Assessment Goal Achievement (SAGA) questionnaire. Secondary outcomes are the effect of TTNS on urodynamic, neurophysiological, and bowel function outcome measures, as well as the safety of TTNS.

CONCLUSIONS

A total of 240 patients with refractory NLUTD will be included and randomized 1:1 into the verum or sham TTNS group from March 2020 until August 2026. TTNS will be performed twice a week for 30 min during 6 weeks. The patients will attend baseline assessments, 12 treatment visits and follow-up assessments at the study end.

[Uroflowmetry: A follow-up tool for neurogenic bladder patients treated by transcutaneous tibial posterior stimulation?]

OBJECTIVE

Neurogenic bladders can suffer from overactivity, underactivity or dyssynergia depending on the level of the initial lesion. These symptoms can lead to severe alterations of the upper urinary tract. One of the first-line treatments is the transcutaneous tibial posterior stimulation (TTNS), which was demonstrated to be efficient on urodynamics. But it is an invasive, expensive and sometimes not patient-accepted examination, contrary to the uroflowmetry. The aim of this study is to assess the feasibility of a follow-up with a uroflowmetry when treated by TTNS and show that the maximum flow rate increased after treatment, displaying a better detrusor contraction.

METHODS

In total, 38 patients with neurogenic bladder undergoing a 12-weeks TTNS treatment and with 2 uroflowmetries interpretable before and after treatment were included. The maximum flow rate (Qmax), the urinated volume and the post-void residual (PVR) were retrieved from the uroflowmetry, and the USP-score and the urinary discomfort were asked at each appointment.

RESULTS

Qmax is increased from 17,53ml/s to 18,26ml/s, as well as the PVR (from 76,97ml to 79,16ml). Urinated volume is decreased from 241,4ml to 193,66ml. Patients feel enhanced after TTNS according to the decrease in the USP-score and the urinary discomfort scale.

CONCLUSION

The increase of the cystomanometric capacity and the delay of the detrusor overactivity due to TTNS explains the reduction of the urinated volume and the increase of PVR. Increased Qmax might show a better voluntary bladder contraction, with a restraint due to the lack of abdominal pressure measurement during voiding.

Efficacy of peripheral electrical nerve stimulation on improvements of urodynamics and voiding diary in patients with neurogenic lower urinary tract dysfunction: a systematic review and meta-analysis

BACKGROUND

Peripheral electrical nerve stimulation is a routinely recommended treatment for non-neurogenic overactive bladder but has not been approved for patients with neurogenic lower urinary tract dysfunction (NLUTD). This systematic review and meta-analysis was to elucidate the efficacy and safety of electrostimulation and thus provide firm evidence for treating NLUTD.

MATERIALS AND METHODS

We systematically performed the literature search through PubMed, Web of Science, and Cochrane Library databases in March 2022. The eligible studies were identified across the inclusion criteria and the data on urodynamic outcomes, voiding diary parameters, and safety was collected to quantitatively synthesize the pooled mean differences (MDs) with 95% CIs. Subgroup analyses and sensitivity analyses were subsequently used to investigate the possible heterogeneity. This report was achieved in accordance with the preferred reporting items for systematic reviews and meta-analyses statement.

RESULTS

A total of 10 studies involving 464 subjects and 8 studies with 400 patients were included for systematic review and meta-analysis, respectively. The pooled effect estimates indicated that electrostimulation could significantly improve urodynamic outcomes, including maximum cystometric capacity (MD=55.72, 95% CI 15.73, 95.72), maximum flow rate (MD=4.71, 95% CI 1.78, 7.65), maximal detrusor pressure (MD=-10.59, 95% CI -11.45, -9.73), voided volume (MD=58.14, 95% CI 42.97, 73.31), and post-void residual (MD=-32.46, 95% CI -46.63, -18.29); for voiding diary parameters, patients undergoing electrostimulation showed lower MDs of incontinence episodes per 24 h (MD=-2.45, 95% CI -4.69, -0.20) and overactive bladder symptom score (MD=-4.46, 95% CI -6.00, -2.91). In addition to surface redness and swelling, no stimulation-related severe adverse events were reported else.

CONCLUSIONS

The current evidence demonstrated that peripheral electrical nerve stimulation might be effective and safe for managing NLUTD, whereas more reliable data from large-scale randomized controlled trials are necessary to strengthen this concept.

Training with noninvasive brain-machine interface, tactile feedback, and locomotion to enhance neurological recovery in individuals with complete paraplegia: a randomized pilot study

In recent years, our group and others have reported multiple cases of consistent neurological recovery in people with spinal cord injury (SCI) following a protocol that integrates locomotion training with brain machine interfaces (BMI). The primary objective of this pilot study was to compare the neurological outcomes (motor, tactile, nociception, proprioception, and vibration) in both an intensive assisted locomotion training (LOC) and a neurorehabilitation protocol integrating assisted locomotion with a noninvasive brain-machine interface (L + BMI), virtual reality, and tactile feedback. We also investigated whether individuals with chronic-complete SCI could learn to perform leg motor imagery. We ran a parallel two-arm randomized pilot study; the experiments took place in São Paulo, Brazil. Eight adults sensorimotor-complete (AIS A) (all male) with chronic (> 6 months) traumatic spinal SCI participated in the protocol that was organized in two blocks of 14 weeks of training and an 8-week follow-up. The participants were allocated to either the LOC group (n = 4) or L + BMI group (n = 4) using block randomization (blinded outcome assessment). We show three important results: (i) locomotion training alone can induce some level of neurological recovery in sensorimotor-complete SCI, and (ii) the recovery rate is enhanced when such locomotion training is associated with BMI and tactile feedback (∆Mean Lower Extremity Motor score improvement for LOC =  + 2.5, L + B =  + 3.5; ∆Pinprick score: LOC =  + 3.75, L + B =  + 4.75 and ∆Tactile score LOC =  + 4.75, L + B =  + 9.5). (iii) Furthermore, we report that the BMI classifier accuracy was significantly above the chance level for all participants in L + B group. Our study shows potential for sensory and motor improvement in individuals with chronic complete SCI following a protocol with BMIs and locomotion therapy. We report no dropouts nor adverse events in both subgroups participating in the study, opening the possibility for a more definitive clinical trial with a larger cohort of people with SCI.Trial registration: http://www.ensaiosclinicos.gov.br/ identifier RBR-2pb8gq.

Effects of nonsurgical, minimally or noninvasive therapies for urinary incontinence due to neurogenic bladder: a systematic review and meta-analysis

Objective

To determine the effects of nonsurgical, minimally or noninvasive therapies on urge urinary incontinence (UUI) symptoms and quality of life (QoL) in individuals with neurogenic bladder (NGB).

Data Sources

Cochrane library, EMBASE, MEDLINE, PEDro, Scopus, and Web of Science databases were searched from inception to September 2021.

Review Methods

Randomized controlled trials that compared therapies such as intravaginal electrical stimulation (IVES), transcutaneous electrical nerve stimulation (TENS), neuromuscular electrical stimulation (NMES), transcutaneous tibial nerve stimulation (TTNS), pelvic floor muscle training (PFMT), and behavioural therapy (BT) to control were included. Study screening, data extraction, and study quality assessments were performed by two independent authors.

Results

Fourteen trials with 804 participants were included in the study after screening of 4281 potentially relevant articles. Meta-analyses revealed a significant effect of electrical stimulation on UUI due to multiple sclerosis (standardized mean difference (SMD): -0.614; 95% confidence interval (CI): -1.023, -0.206; p = 0.003) and stroke (SMD: -2.639; 95% CI: -3.804, -1.474; p = 0.000). The pooled analyses of TTNS (weighted mean difference (WMD): -12.406; 95% CI: -16.015, -8.797; p = 0.000) and BT (WMD: -9.117; 95% CI: -14.746, -3.487; p = 0.002) revealed significant effects of these interventions on QoL in people with Parkinson's disease. However, meta-analyses revealed nonsignificant effects for PFMT (WMD: -0.751; 95% CI: -2.426, 0.924; p = 0.380) and BT (WMD: -0.597; 95% CI: -1.278, 0.083; p = 0.085) on UUI due to Parkinson's disease.

Conclusions

Our meta-analyses found electrical stimulation to be beneficial for improving the symptoms of UUI among people with multiple sclerosis and those with stroke. Our review also revealed that TTNS and BT might improve QoL for people with NGB due to Parkinson's disease, although the effects of PFMT and BT on UUI warrant further investigation.

Avicenna and clinical experiences in Canon of Medicine

Avicenna used his medical knowledge and experience of scientists from different nations to create a new style in medicine. For this reason, his textbook, Canon of Medicine, has been considered a medical reference in all universities worldwide for centuries. In this article, some valuable and interesting diagnostic and therapeutic clinical experiences mentioned in the Canon of Medicine are described in five sections. This research was conducted to review Avicenna’s specific clinical observations and interventions in PubMed, Google Scholar, and Scopus databases using the keywords “Avicenna” and “Canon of Medicine”. In this article, we presented several examples of diagnostic and therapeutic clinical experiences mentioned in the Canon of Medicine in 5 areas, including semiology, therapeutic strategy, urology, neurology, obstetrics, and gynecology. Canon of Medicine, as a complete medical series containing the medical experiences from different nations and Iranian medical scientists, has influenced the world’s medical knowledge for several centuries. Some of Avicenna’s clinical and experimental views can be useful from both a historical point of view and new research.

Efficacy of percutaneous and transcutaneous posterior tibial nerve stimulation on idiopathic overactive bladder and interstitial cystitis/painful bladder syndrome: A systematic review and meta-analysis

OBJECTIVES

Percutaneous and transcutaneous posterior tibial nerve stimulation (PTNS and TTNS) showed a promising effect on overactive bladder (OAB) and interstitial cystitis/painful bladder syndrome. We aimed to give a systematic review and meta-analysis on the efficacy and safety of these therapeutic methods as well.

METHODS

We searched studies available on PubMed, Embase, Cochrane, Scopus, Web of Science, and ProQuest on March 31, 2021, to find both published and unpublished studies. The retrieved articles were screened by two independent researchers and then the selected studies were critically appraised by Cochrane risk-of-bias tool for randomized trials, and Joanna Briggs Institute's checklist for quasi-experimental studies. Finally, the results of studies were synthesized using Review Manager (RevMan) 5.4 statistical software when the data were homogenous. The meta-analysis was performed by calculating the effect size (mean difference) and their 95% confidence intervals (CIs).

RESULTS

Of the total 3194 publications, 68 studies were included in our qualitative evaluation and 9 studies (11 trials) in the quantitative stage. When TTNS or PTNS were compared to sham, placebo, no treatment, or conservative management, a decrease in frequency of urination was observed in both TTNS (mean difference [MD]: -3.18, 95% CI: -4.42 to -1.94, and p < 0.00001), and PTNS (MD: -2.84, 95% CI: -4.22 to -1.45, and p < 0.00001), and overall TTNS or PTNS (MD: -2.95, 95% CI: -4.01 to -1.88, and p < 0.00001). Significant improvements in mean voiding volume (MVV) and decreasing nocturia were also observed.

CONCLUSIONS

Nerve stimulations either PTNS or TTNS appear to be effective interventions in treating refractory idiopathic OAB in terms of daily voiding frequency, MVV, urgency episodes, and nighttime voiding frequency. However, our result did not show any improvement in terms of urinary incontinence, postvoid residual volume or urge incontinence, and maximum cystometric capacity which emphasized the efficacy of these modalities on dry-OAB rather than wet-OAB.

Long-Term Effect of Early Post-operative Transcutaneous Electrical Stimulation on Voiding Function After Radical Hysterectomy: A Multicenter, Randomized, Controlled Trial

Introduction: Post-radical-hysterectomy (RH) patients suffer from a series of problems resulting from neurovascular injury, such as bladder dysfunction, which reduce their quality of life. We have designed this study to evaluate the efficacy of transcutaneous electrical stimulation (TENS) on patient rehabilitation after RH for early cervical cancer.

Materials and methods: A total of 97 patients were enrolled in a randomized-controlled trial (from January 2015 to December 2019) involving 7 medical centers nationwide. Patients were assigned to either the intervention group (n = 46), or the control group (n = 51). TENS was given to patients in the intervention group from the 7^th day after surgery for a total of 14–21 days. The control group received no TENS. Primary outcomes were measured for residual urine volume and recovery of urination function. Secondary outcomes were measures for urodynamics (UDS), pelvic floor electromyography function examination (PFEmF), and quality of life (QoL).

Results: Residual urine volume and improvement in the rate of urination were found to show no significant differences on the 14^th, 21^st, and 28^th days after surgery. The maximum flow rate (Qmax) in the intervention group was significantly higher than that in the control group on the 28^th day, but there were no significant differences in average flow rate, voiding time, time to Qmax, muscle fiber strength, muscle fiber fatigue, and the abnormal rate of A3 reflection on the 28^th day and the 3^rd mo., as well as in the QoL at 3^rd mo., 6^th mo., and 12^th mo. after surgery.

Conclusion: Our study showed no sufficient evidence to prove that TENS under the trialed parameters could improve the subject's voiding function, PFEmF, and QOL after RH. This has provided valuable data for rehabilitation after RH.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02492542.

Neurogenic bladder - concepts and treatment recommendations

Introduction:

Bladder and urinary sphincter malfunctioning that results from some change in the central and/or peripheral nervous system is defined as neurogenic bladder. The urinary tract symptoms that can be related to its filling, emptying, or both have a significant impact on the quality of life of individuals. The present review was based on the document prepared for the public health system in Brazil as a treatment guidelines proposal.

Material and Methods:

Survey questions were structured as per PICO (Population, Intervention, Control, and Outcome). Search strategies were defined and performed in the MEDLINE/Pubmed, Embase, Epistemonikos and Google Scholar databases. The selection of articles followed the evidence hierarchy concept; evidence body was identified, and the quantitative study data were extracted. The quality of evidence and grade of recommendation were qualitatively assessed according to GRADE (Grading of Recommendations, Assessment, Development and Evaluations).

Results:

A total of 2.707 articles were identified, with 49 of them being selected to compose the basis for this review. Neurogenic bladder treatments were classified according to their focus on filling or emptying symptoms and sub- classified in pharmacological and surgical treatments.

Conclusion:

Treatment guidelines are important tools for the public health system to promote the best practice when treating neurogenic bladder patients.

Transcutaneous Electrical Stimulation for Neurogenic Bladder Dysfunction Following Spinal Cord Injury: Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

To assess the efficacy of transcutaneous electrical nerve stimulation (TENS) for neurogenic bladder dysfunction secondary to spinal cord injury (SCI).

MATERIALS AND METHODS

A systematic search of MEDLINE, EMBASE, Web of Science, Scopus, and Cochrane libraries up to February 2021 was performed using PRISMA methodology. All randomized controlled trials (RCTs) that studied TENS for neurogenic bladder in a SCI population were included. The primary outcomes of interest were maximum cystometric capacity (MCC) and maximum detrusor pressure (Pdet). Meta-analysis was conducted with RevMan v5.3.

RESULTS

Six RCTs involving 353 participants were included. Meta-analysis showed that TENS significantly increased MCC (standardized mean difference 1.11, 95% confidence interval [CI] 0.08-2.14, p = 0.03, I²  = 54%) in acute SCI. No benefits were seen for maximum Pdet. TENS was associated with no major adverse events.

CONCLUSIONS

TENS may be an effective, safe intervention for neurogenic bladder dysfunction following SCI. Further studies are essential to confirm these results and more work is required to determine optimal stimulation parameters and duration of the treatment.

Transcutaneous Electrical Nerve Stimulation and Percutaneous Tibial Nerve Stimulation to Treat Idiopathic Nonobstructive Urinary Retention: A Systematic Review

CONTEXT

Transcutaneous electrical nerve stimulation (TENS) and percutaneous tibial nerve stimulation (PTNS) provide minimally invasive ways to treat idiopathic nonobstructive urinary retention (NOUR).

OBJECTIVE

To assess the efficacy of TENS and PTNS for treating idiopathic NOUR.

EVIDENCE ACQUISITION

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Embase, Medline, Web of Science Core Collection, and the Cochrane CENTRAL register of trials were searched for all relevant publications until April 2020.

EVIDENCE SYNTHESIS

A total of 3307 records were screened based on the title and abstract. Eight studies met the inclusion criteria and none of the exclusion criteria. Five studies, all from the same group, reported the efficacy of PTNS and two that of TENS in adults with idiopathic NOUR. One study reported the efficacy of TENS in children with idiopathic NOUR. Objective success was defined as a ≥50% decrease in the number of catheterizations per 24 h or in the total catheterized volume in 24 h. The objective success rate of PTNS ranged from 25% to 41%. Subjective success was defined as the patient's request for continued chronic treatment with PTNS, and ranged from 46.7% to 59%. Eighty percent of women who underwent transvaginal stimulation reported an improvement such as a stronger stream when voiding. TENS in children reduced postvoid residual and urinary tract infections.

CONCLUSIONS

The efficacy of TENS and PTNS in the treatment of idiopathic NOUR is limited and should be verified in larger randomized studies before application in clinical practice.

PATIENT SUMMARY

The outcomes of transcutaneous electrical nerve stimulation and percutaneous tibial nerve stimulation for the treatment of urinary retention of unknown origin were reviewed. Whether these treatments are superior to other treatments could not be established.

Update from TASCI, a Nationwide, Randomized, Sham-controlled, Double-blind Clinical Trial on Transcutaneous Tibial Nerve Stimulation in Patients with Acute Spinal Cord Injury to Prevent Neurogenic Detrusor Overactivity

Transcutaneous tibial nerve stimulation has the potential to revolutionize the management of lower urinary tract dysfunction in patients with acute spinal cord injury. TASCI is a nationwide randomized, sham-controlled, double-blind clinical trial for which the preparatory phase has been successfully completed.

TASCI-transcutaneous tibial nerve stimulation in patients with acute spinal cord injury to prevent neurogenic detrusor overactivity: protocol for a nationwide, randomised, sham-controlled, double-blind clinical trial

INTRODUCTION

Neurogenic lower urinary tract dysfunction (NLUTD), including neurogenic detrusor overactivity (NDO) and detrusor sphincter dyssynergia, is one of the most frequent and devastating sequelae of spinal cord injury (SCI), as it can lead to urinary incontinence and secondary damage such as renal failure. Transcutaneous tibial nerve stimulation (TTNS) is a promising, non-invasive neuromodulatory intervention that may prevent the emergence of the C-fibre evoked bladder reflexes that are thought to cause NDO. This paper presents the protocol for TTNS in acute SCI (TASCI), which will evaluate the efficacy of TTNS in preventing NDO. Furthermore, TASCI will provide insight into the mechanisms underlying TTNS, and the course of NLUTD development after SCI.

METHODS AND ANALYSIS

TASCI is a nationwide, randomised, sham-controlled, double-blind clinical trial, conducted at all four SCI centres in Switzerland. The longitudinal design includes a baseline assessment period 5-39 days after acute SCI and follow-up assessments occurring 3, 6 and 12 months after SCI. A planned 114 participants will be randomised into verum or sham TTNS groups (1:1 ratio), stratified on study centre and lower extremity motor score. TTNS is performed for 30 min/day, 5 days/week, for 6-9 weeks starting within 40 days after SCI. The primary outcome is the occurrence of NDO jeopardising the upper urinary tract at 1 year after SCI, assessed by urodynamic investigation. Secondary outcome measures assess bladder and bowel function and symptoms, sexual function, neurological structure and function, functional independence, quality of life, as well as changes in biomarkers in the urine, blood, stool and bladder tissue. Safety of TTNS is the tertiary outcome.

ETHICS AND DISSEMINATION

TASCI is approved by the Swiss Ethics Committee for Northwest/Central Switzerland, the Swiss Ethics Committee Vaud and the Swiss Ethics Committee Zürich (#2019-00074). Findings will be disseminated through peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03965299.

Single subject and group whole-brain fMRI mapping of male genital sensation at 7 Tesla

Processing of genital sensations in the central nervous system of humans is still poorly understood. Current knowledge is mainly based on neuroimaging studies using electroencephalography (EEG), magneto-encephalography (MEG), and 1.5- or 3- Tesla (T) functional magnetic resonance imaging (fMRI), all of which suffer from limited spatial resolution and sensitivity, thereby relying on group analyses to reveal significant data. Here, we studied the impact of passive, yet non-arousing, tactile stimulation of the penile shaft using ultra-high field 7T fMRI. With this approach, penile stimulation evoked significant activations in distinct areas of the primary and secondary somatosensory cortices (S1 & S2), premotor cortex, insula, midcingulate gyrus, prefrontal cortex, thalamus and cerebellum, both at single subject and group level. Passive tactile stimulation of the feet, studied for control, also evoked significant activation in S1, S2, insula, thalamus and cerebellum, but predominantly, yet not exclusively, in areas that could be segregated from those associated with penile stimulation. Evaluation of the whole-brain activation patterns and connectivity analyses indicate that genital sensations following passive stimulation are, unlike those following feet stimulation, processed in both sensorimotor and affective regions.

Electrical stimulation in the treatment of bladder dysfunction: technology update

The urinary bladder has two functions: urine storage and voiding. Clinically, two major categories of lower urinary tract symptoms can be defined: storage symptoms such as incontinence and urgency, and voiding symptoms such as feeling of incomplete bladder emptying and slow urinary stream. Urgency to void with or without incontinence is called overactive bladder (OAB). Slow urinary stream, hesitancy, and straining to void with the feeling of incomplete bladder emptying are often called underactive bladder (UAB). The underlying causes of OAB or UAB can be either non-neurogenic (also referred to as idiopathic) and neurogenic, for example due to spinal cord injury or multiple sclerosis. OAB and UAB can be treated conservatively by lifestyle intervention or medication. In the case that conservative treatment does not provide sufficient benefit, electrical stimulation can be used. Sacral neurostimulation or neuromodulation (SNM) is offered as a third-line therapy to patients with non-neurogenic OAB or UAB. In SNM, the third or fourth sacral nerve root is stimulated and after a test period, a neuromodulator is implanted in the buttock. Until recently only a non-rechargeable neuromodulator was approved for clinical use. However, nowadays, a rechargeable sacral neuromodulator is also on the market, with similar safety and effectiveness to the non-rechargeable SNM system. The rechargeable device was approved for full body 1.5T and 3T MRI in Europe in February 2019. Regarding neurogenic lower urinary tract dysfunction, electrical stimulation only seems to benefit a selected group of patients.

Immediate effect of transcutaneous electrical nerve stimulation on urodynamic parameters of children with myelomeningocele

OBJECTIVE

To evaluate the immediate response of electrical stimulation in children with neurogenic bladder (NB) due to myelomeningocele, using the urodynamic study (UDS).

METHODS

This is a nonrandomized intervention study with 26 children with neurogenic overactive bladder and low bladder compliance due to myelomeningocele, aged 5 to 15 years. Each child performed a routine UDS and then a second UDS, during which the electrical stimulation was applied in the parasacral region. The main outcome was the difference in the maximum bladder pressure observed between the two urodynamic studies, analyzed from the paired t test.

RESULTS

We found that 77% of the patients had a lower maximum bladder pressure in the test with electrostimulation compared with the ones without electrostimulation. On average, the pressure reduction after stimulation was 7.24 cmH₂ O (95% confidence interval [CI], 0.35-14.14; P = .04). The reduction was even higher in children under 12 years of age, compared with the children above 12 years (11.29 cmH₂ O, 95% CI, 3.47-19.12; P = .01).

CONCLUSION

The use of transcutaneous electrical nerve stimulation had a significant immediate effect on reducing the maximum bladder pressure during the urodynamic studies among the tested pediatric patients with NB. The results were more significant among children under 12 years of age.

Effects of Genital Nerve Stimulation Amplitude on Bladder Capacity in Spinal Cord Injured Subjects

Background/Purpose

Few studies have investigated the effects of changing the amplitude of dorsal genital nerve stimulation (GNS) on the inhibition of neurogenic detrusor overactivity in individuals with spinal cord injury (SCI). The present study determined the acute effects of changes in GNS amplitude on bladder capacity gain in individuals with SCI and neurogenic detrusor overactivity.

Methods

Cystometry was used to assess the effects of continuous GNS on bladder capacity during bladder filling. The cystometric trials were conducted in a randomized sequence of cystometric fills with continuous GNS at stimulation amplitudes ranging from 1 to 4 times of threshold (T) required to elicit the genitoanal reflex.

Results

The bladder capacity increased minimally and maximally by approximately 34% and 77%, respectively, of the baseline bladder capacity at 1.5 T and 3.2 T, respectively. Stimulation amplitude and bladder capacity were significantly correlated (R = 0.55, P = 0.01).

Conclusion

This study demonstrates a linear correlation between the stimulation amplitude ranging from 1 to 4T and bladder capacity gain in individuals with SCI in acute GNS experiments. However, GNS amplitude out of the range of 1-4T might not be exactly a linear relationship due to subthreshold or saturation factors. Thus, further research is needed to examine this issue. Nevertheless, these results may be critical in laying the groundwork for understanding the effectiveness of acute GNS in the treatment of neurogenic detrusor overactivity.

[Neuromodulation of lower urinary tract dysfunction]

Neuromodulative procedures such as transcutaneous electrical nerve stimulation (TENS), transcutaneous/percutaneous tibial nerve stimulation (TTNS/PTNS), and sacral neuromodulation (SNM) are promising second-line treatments for refractory lower urinary tract dysfunction. Using these therapies, both storage and voiding disorders but also bowel dysfunction might be successfully treated. Although the mechanism of action of neuromodulation is not well understood, it seems to involve modulation of spinal cord reflexes and brain networks by peripheral afferents (genital/rectal, tibial and sacral afferents in the case of TENS, TTNS/PTNS, and SNM, respectively). Neuromodulative procedures might also be highly effective in the most desperate situations and further relevant developments are expected so that these innovative techniques will most likely become even more important in urology.

Bladder emptying method is the primary determinant of urinary tract infections in patients with spinal cord injury: results from a prospective rehabilitation cohort study

OBJECTIVE

To understand the occurrence of and risk factors for urinary tract infections (UTIs) in patients with spinal cord injury (SCI) undergoing specialized SCI rehabilitation in Switzerland.

PATIENTS AND METHODS

This study used data collected from 369 patients, who participated in a nationwide rehabilitation cohort for SCI in Switzerland between 2013 and 2017. Information on UTIs as well as their potential determinants, including demographics, lesion characteristics, and time-updated data on functional independence and bladder management, was used. Multivariable regression methods were applied to perform a time-updated evaluation of determinants of UTI risk.

RESULTS

The crude incidence rate (IR) of UTIs was 0.55 UTIs per 100 person-days (95% confidence interval [CI] 0.49-0.62), the cumulative IR was 43%, and the median length of stay was 122 days. The bladder emptying method at discharge was largely determined by 28 days after admission. Among those using indwelling or assisted intermittent catheterization (IC), the likelihood of self-IC at discharge was positively related to the level of self-care independence, negatively related to age at injury, and lower in women than men. Catheter users consistently had higher adjusted IRs for UTI than spontaneous voiders. The IR ratios were: indwelling catheter: 5.97 (95% CI 2.63-13.57); assisted IC: 6.05 (95% CI 2.63-13.94); self-IC: 5.16 (95% CI 2.31-11.52); test for differences across catheter groups: P = 0.82. Lesion severity and previous UTI had additional but smaller effect sizes.

CONCLUSIONS

Bladder emptying method was identified as the main risk factor for UTI in patients with SCI. As spontaneous voiders had the lowest UTI rate, further research is warranted to reduce voiding dysfunction, for instance using neuromodulation procedures.

Conditional neuromodulation of neurogenic detrusor overactivity using transrectal stimulation in patients with spinal cord injury: A proof of principle study

AIMS

A proof of principle study of a novel wearable device to control neurogenic detrusor over-activity in eight male spinal cord injured subjects using conditional neuromodulation.

METHODS

Transrectal stimulation was delivered through the device in response to simultaneously recorded external anal sphincter (EAS) contraction as a marker for neurogenic detrusor overactivity (NDO). The effect of conditional neuromodulation on bladder capacity and maximum detrusor pressure was investigated in addition to reliability of dyssynergic sphincter contraction as a marker for NDO.

RESULTS

Conditional neuromodulation through the novel device showed a statistically significant increase in bladder capacity and reduction in maximum detrusor pressure in six male subjects with spinal cord injury (SCI). EAS activity was a reliable surrogate for detection of NDO.

CONCLUSIONS

It has been shown for the first time that conditional neuromodulation can be delivered and triggered via a single biocompatible device placed in the anal canal. The pudendal nerves lying in Alcock's canal were stimulated through the wall of the anal canal, and the dyssynergic activity of the EAS was used to detect NDO and trigger neuromodulation giving significant increases in bladder capacity and reduction in detrusor pressure in six male subjects with SCI.

A systematic review of the diagnosis and treatment of patients with neurogenic hyperactivity of the detrusor muscle

BACKGROUND

Neurogenic detrusor hyperactivity (NDH) is a urodynamic observation characterised by involuntary detrusor contractions during the filling phase that are caused by an underlying neurological disease. The common and severe complications that can result from NDH warrant the preparation of healthcare protocols for the proper management of patients with NDH.

OBJECTIVE

The aim of this study is to standardise the criteria for the decision-making process in the management of patients with diagnosed or suspected NDH, providing personalised medical care.

ACQUISITION OF EVIDENCE

We performed a systematic noncomprehensive literature review on the aspects of the diagnosis and treatment of NDH. Based on the review, recommendations were issued by nominal consensus of a group of urology specialists.

SYNTHESIS OF THE EVIDENCE

In general, the diagnosis of NDH is arrived at by a proper review of the medical history, physical examination and voiding diary before performing any diagnostic study. The main treatment objectives are to protect the upper urinary tract, restore function of the lower tract and improve these patients' continence and quality of life. The treatment consists of several steps aimed at obtaining proper bladder storage that allows for sufficiently spaced voidings. The follow-up should be personalised based on each patient's needs.

CONCLUSIONS

The identification and management of NDH is important for positively redirecting the function of the lower urinary tract, in terms of filling and voiding, thereby improving the patients' quality of life.

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.

Prediction of Bladder Outcomes after Traumatic Spinal Cord Injury: A Longitudinal Cohort Study

BACKGROUND

Neurogenic bladder dysfunction represents one of the most common and devastating sequelae of traumatic spinal cord injury (SCI). As early prediction of bladder outcomes is essential to counsel patients and to plan neurourological management, we aimed to develop and validate a model to predict urinary continence and complete bladder emptying 1 y after traumatic SCI.

METHODS AND FINDINGS

Using multivariate logistic regression analysis from the data of 1,250 patients with traumatic SCI included in the European Multicenter Spinal Cord Injury study, we developed two prediction models of urinary continence and complete bladder emptying 1 y after traumatic SCI and performed an external validation in 111 patients. As predictors, we evaluated age, gender, and all variables of the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and of the Spinal Cord Independence Measure (SCIM). Urinary continence and complete bladder emptying 1 y after SCI were assessed through item 6 of SCIM. The full model relies on lower extremity motor score (LEMS), light-touch sensation in the S3 dermatome of ISNCSI, and SCIM subscale respiration and sphincter management: the area under the receiver operating characteristics curve (aROC) was 0.936 (95% confidence interval [CI]: 0.922-0.951). The simplified model is based on LEMS only: the aROC was 0.912 (95% CI: 0.895-0.930). External validation of the full and simplified models confirmed the excellent predictive power: the aROCs were 0.965 (95% CI: 0.934-0.996) and 0.972 (95% CI 0.943-0.999), respectively. This study is limited by the substantial number of patients with a missing 1-y outcome and by differences between derivation and validation cohort.

CONCLUSIONS

Our study provides two simple and reliable models to predict urinary continence and complete bladder emptying 1 y after traumatic SCI. Early prediction of bladder function might optimize counselling and patient-tailored rehabilitative interventions and improve patient stratification in future clinical trials.