Sacral neuromodulation in patients with neurogenic lower urinary tract dysfunction

[Importance of neuro-urological care in patients with spinal cord injuries/diseases]

Integrity, control and regulation of the urinary tract are subject to a complex neuronal regulation, in which portions of the sympathetic, parasympathetic and somatic nervous system are involved. The spinal cord plays a central role in regulation and serves as a transmitter for the motor and sensory pathways. Bladder dysfunction followed by renal dysfunction was the most frequent cause of death in patients with spinal cord injuries/diseases (paraplegia) as recently as half a decade ago. Thanks mainly to diagnostic and therapeutic advances made in neuro-urology, urological problems are no longer life-limiting. A vital role is played not only by the actual function of the urinary tract but also by the complex interactions in patients living with paraplegia. Issues such undertreated hyperactivity of the detrusor muscle with autonomous dysregulation, incontinence with secondary skin changes, or insufficient hand function to perform intermittent catheterisation must be evaluated in an interdisciplinary approach. Spinal cord injury/disease implies numerous functional disorders and secondary impairments of the organism. In addition to bladder function, sexual dysfunction also plays a crucial role. Especially in younger patients who sustain paraplegia before or during the family planning phase, this disruption and limitation is an essential reason for reduced quality of life. Neurogenic intestinal function plays an additional crucial role with regard to quality of life and management of everyday life. In recent years, the range of neuro-urological topics has expanded significantly. The focus of our work shifted from being merely on the urinary tract and urodynamics. In particular, the diagnostic investigation and treatment of neurogenic intestinal dysfunction is increasingly in the hands of neuro-urologists. The complex presentation of paraplegia involves an interaction of bladder, intestinal and sexual dysfunction in a way that these influence one another. Therefore, the sustained care and re-integration of these patients essentially includes lifelong and regular neuro-urological care in a paraplegia centre. Last but not least, it is exactly these neuro-urological topics such as urinary tract infections, urinary and intestinal incontinence and faecal impaction, which most commonly lead to re-hospitalisation.

Effects of repetitive functional magnetic stimulation in the sacral nerve in patients with neurogenic detrusor overactivity after suprasacral spinal cord injury: a study protocol for a randomized controlled trial

BACKGROUND

Neurogenic detrusor overactivity (NDO) is a serious and common complication after spinal cord injury, affecting patients' quality of life seriously. Therefore, we developed this research protocol to evaluate the efficacy of repetitive functional magnetic stimulation (rFMS) in the sacral nerve in patients with neurogenic detrusor overactivity (NDO) after suprasacral spinal cord injury (SCI) and provide more options for rFMS in treating NDO after suprasacral SCI.

METHODS

This study is a single-center, randomized, parallel-group clinical trial. We will recruit the patients with NDO after suprasacral SCI in the Rehabilitation Department of the Affiliated Hospital of Southwest Medical University from September 2022 to August 2023. They will be assigned to the rFMS group and the sham stimulation group randomly. The sample size is 66, with 33 patients in each group. The rFMS group will receive real rFMS treatment of the sacral nerve (100% stimulation intensity, 5 Hz, 20 min each time, five times a week), and the sham group will receive sham stimulation. Both groups will receive similar treatment strategies, including medication, standard urine management, acupuncture treatment, and health education. The bladder compliance (bladder capacity/detrusor pressure) and pudendal nerve electromyography will be evaluated at baseline, 8th week of treatment. The residual volume of the bladder and bladder diary will be recorded once a week during 8 weeks of treatments. SCI-QOL and NBSS will be evaluated at baseline, the 4th and 8th week of treatment. In addition, the above assessments will be followed up at 8 weeks after the end of treatment.

DISCUSSION

It is expected that the bladder function, symptoms, and quality of life might be significantly improved after rFMS of the sacral nerve.

TRIAL REGISTRATION

The China Clinical Trials Registry has approved this study, registration number: ChiCTR2100045148. Registered on April 7, 2021.

Effectiveness and safety of sacral neuromodulation for neurogenic bladder

BACKGROUND

The treatment of neurogenic bladder (NB) is a challenge because conventional therapy often fails. Sacral neuromodulation (SNM) is a minimally invasive technique and an unconventional treatment for neurogenic bladder. Its research is still in the exploratory stage. The research on its effectiveness and safety is not clear.

OBJECTIVE

To assess the effectiveness and safety of sacral neuromodulation (SNM) for neurogenic bladder (NB).

METHODS

By searching the PubMed databases and Cochrane Library databases, combined with the method of literature tracing, the clinical researches and works on neurogenic bladder and sacral neuromodulation therapy were collected. Two reviewers independently selected and extracted data, (1) determine whether the study meets the inclusion criteria and exclude the literature that meets the exclusion criteria. (2) Researchers' screening results and data, if there are differences in the results, will be discussed to eliminate the differences. (3) Read the full text of the literature carefully to determine the final literature to be included. (4) The relevant data of 11 independent studies, a total of 291 patients, were systematically reviewed using review manager 5.3 software.

RESULTS

This research included 11 independent studies with a total of 291 patients. The improvements of main outcomes before and after SNM therapy were significant: incontinence episodes /24 h (WMD -2.52; 95%CI-3.14-1.90; p <0.001), frequency/24 h (WMD-5.96; 95%CI -6.27，-5.66; p <0.001), voiding volume (WMD 116.09 mL; 95%CI 86.68，145.51; p <0.001), cystometric capacity (WMD 129.84 mL; 95%CI 100.53, 159.15; p <0.001), post-void residual volume (WMD-198.00 mL; 95%CI-264.60, -131.40; p <0.001), clean intermittent self-catheterization/24 h (WMD-2.48; 95%CI -2.96, -2.00; p <0.001).

CONCLUSION

This systematic review indicated that the sacral neuromodulation treatment for neurogenic bladder was effective and safe.

Sacral neuromodulation for neurological disease-induced lower urinary tract symptoms in Saudi Arabia: a single-centre experience

Objective

To evaluate the effectiveness of sacral neuromodulation therapy (SNM) for lower urinary tract symptoms (LUTS) caused by neurological diseases.

Methods

This prospective cohort study enrolled patients that developed LUTS secondary to neurological disorders. All patients underwent staged SNM. A 5-day voiding diary was used to evaluate their response to the stage 1 procedure. Implantation of the full system during the stage 2 procedure was undertaken in patients that had ≥50% improvement on their voiding diary.

Results

Twenty-one patients were included in the study with the following neurological aetiologies: diabetes mellitus (n = 2), myelitis (n = 3), multiple sclerosis (n = 5), spinal cord injury (n = 10) and cerebrovascular accident (n = 1). Fifteen patients underwent the stage 1 procedure successfully; their mean age was 47.5 years and the mean follow-up was 29 months. SNM resulted in significantly increased voided volume/void/day, decreased leaking episodes/day, decreased postvoiding residual/day and decreased number of clean intermittent catheterization/day compared with baseline. Five patients were highly satisfied, nine were moderately satisfied and one patient was not satisfied with the therapy.

Conclusion

SNM was an effective therapy for LUTS caused by neurological disease and there was a high rate of patient satisfaction.

Interventional management and surgery of neurogenic lower urinary tract dysfunction in patients with chronic spinal cord injury: A urologist's perspective

Neurogenic lower urinary tract dysfunction (NLUTD) caused by spinal cord injury (SCI) is challenging for urologists. NLUTD not only affects the quality of life but also endangers the upper urinary tract of patients with chronic SCI. Considering that the bladder and urethral function change with time, regular follow-up of NLUTD is necessary, and any complication should be adequately treated. The first priority of bladder management in patients with chronic SCI manifesting NLUTD should be renal function preservation, followed by the normalization of lower urinary tract function. The quality of life should also be assessed. Patients who have a high risk for impaired renal function should be more frequently identified and investigated. Conservative treatment and pharmacological therapy should be started as early as possible. Intravesical or urethral injections of botulinum toxin A is an alternative treatment for refractory NLUTD. When surgical intervention is necessary, less invasive and reversible procedures should be considered first. Improving patients' quality of life and willingness to undergo bladder management is the most important aspect of treatment.

Neuromodulation for Storage Lower Urinary Tract Symptoms in Parkinson Disease: A Systematic Review

BACKGROUND

Bladder symptoms are common in Parkinson disease (PD), affecting quality of life. Medications commonly used such as antimuscarinics can cause frequently intolerable side effects, and therefore, new, better tolerated approaches are needed. Neuromodulation techniques have an established role in urologic disorders; these techniques include tibial nerve stimulation (TNS) and sacral neuromodulation (SNM), which are localized therapies lacking the side effects associated with medication.

OBJECTIVES

This study aimed to undertake a systematic review of the literature reporting the use of neuromodulation techniques for the treatment of bladder symptoms in PD and related conditions.

MATERIALS AND METHODS

A systematic search of data bases was conducted including MEDLINE, CENTRAL, and Web of Science. Studies were required to present specific outcomes for individuals with PD for neuromodulation interventions.

RESULTS

Ten primary studies were identified concerning detailed outcomes of neuromodulation on bladder symptoms in PD, including seven for TNS, one for SNM, and one using transcranial magnetic stimulation (TMS). Two further mixed cohort studies documented minimal data on individuals with PD. All studies demonstrated benefit in a range of outcome measures following neuromodulation. Two randomized sham-controlled studies were carried out using TNS, with one clearly demonstrating superiority over sham, although difficulties with achieving believable yet ineffective sham treatment are highlighted. Further studies reported limited, uncontrolled outcomes of SNM in patients with PD, demonstrating benefit.

CONCLUSIONS

Evidence from case series suggests benefit from TNS in PD, with limited literature on SNM or TMS. Placebo effect from neuromodulation is a concern, and only limited controlled data exist. Future well-designed and sham-controlled studies need to be completed to provide definitive data on the benefit of neuromodulation in PD. Definitively proving the utility of a neuromodulation modality will allow better treatment of bladder symptoms without the need for pharmacologic measures that cause side effects.

Meeting Proceedings for SCI 2020: Launching a Decade of Disruption in Spinal Cord Injury Research

The spinal cord injury (SCI) research community has experienced great advances in discovery research, technology development, and promising clinical interventions in the past decade. To build upon these advances and maximize the benefit to persons with SCI, the National Institutes of Health (NIH) hosted a conference February 12-13, 2019 titled "SCI 2020: Launching a Decade of Disruption in Spinal Cord Injury Research." The purpose of the conference was to bring together a broad range of stakeholders, including researchers, clinicians and healthcare professionals, persons with SCI, industry partners, regulators, and funding agency representatives to break down existing communication silos. Invited speakers were asked to summarize the state of the science, assess areas of technological and community readiness, and build collaborations that could change the trajectory of research and clinical options for people with SCI. In this report, we summarize the state of the science in each of five key domains and identify the gaps in the scientific literature that need to be addressed to move the field forward.

Systematic Literature Review and Meta-Analysis of Sacral Neuromodulation (SNM) in Patients with Neurogenic Lower Urinary Tract Dysfunction (nLUTD): Over 20 Years' Experience and Future Directions

INTRODUCTION

Sacral neuromodulation (SNM) has been used in carefully selected patients with neurogenic lower urinary tract dysfunctions (nLUTD) for over two decades.

METHODS

The aim of the current work was to perform a systematic literature review and meta-analysis of studies reporting the safety and effectiveness of SNM in patients with nLUTD (neurogenic detrusor overactivity, non-obstructive urinary retention, or a combination of both). For this purpose a systematic literature research was conducted using Embase (OvidSP), MEDLINE (OvidSP), MEDLINE In-Process Citations & Daily Update (OvidSP), MEDLINE (OvidSP) e-Pub ahead of print, Cochrane Central Register of Controlled Trials (CENTRAL), NIH Clinicaltrials.gov, and WHO International Clinical Trials Registry Platform (ICTRP) between 1998 and March 2020, supplemented by a hand search.

RESULTS

Forty-seven studies were included in the systematic literature review. Twenty-one studies comprising a total of 887 patients were included in the meta-analysis of test SNM. The pooled success rate of SNM test stimulation was 66.2% (95% CI 56.9-74.4). Depending on neurogenic conditions test success rates varied greatly. Twenty-four studies with a total of 428 patients were included in the meta-analysis of permanent SNM. The success rate of pooled permanent SNM was 84.2% (95% CI 77.8-89.0). Among the identified studies, the most common adverse events (AEs) were loss of effectiveness, infection, pain at implant site, and lead migration with AE rates of 4.7%, 3.6%, 3.2%, and 3.2%, respectively. Limitations entail lower level of evidence (Oxford classification 3-4) of included studies, significant risk of bias, small sample sizes in some studies, the inclusion of retrospective case series, substantial between-study heterogeneity, heterogeneous patient populations, insufficient disease classification, and variations in terms of outcome parameters as well as techniques. Furthermore, long-term data are limited.

CONCLUSION

This meta-analysis supports not only the benefits of permanent SNM for various nLUTDs but also high overall success rates, similar to idiopathic patients. Current data of the analyzed studies showed that SNM is safe for these patients. However, more vigorous studies and/or registries are needed before definitive conclusions can be drawn.

Safety of Magnetic Resonance Imaging in patients under Sacral Neuromodulation with an InterStim Neuromodulator

OBJECTIVE

To retrospectively investigate the safety of magnetic resonance imaging (MRI) in patients under sacral neuromodulation (InterStim II).

METHODS

Data of patients who received a sacral neuromodulator at the urological department of a Swiss center of tertiary care from 2007 to 2018 and subsequently received at least 1 MRI with implanted device were retrospectively analyzed. Patient characteristics, data on implantation, MRI characteristics and complications potentially related to the MRI were analyzed. In addition, patient interviews were performed to verify the data gathered from patient records.

RESULTS

A total of 55 consecutive patients with a median age of 48 years (range 16 - 80 years) and a total of 191 MRIs (median 3, range 1 - 13) were included to the study. The majority of MRIs (92%) were performed with 1.5 Tesla. The majority of the 1.5 Tesla (58%) as well as 3 Tesla (56%) MRIs assessed body regions other than the head. Complication possibly related to the MRI were only found in 2 (1%) MRI scans in two patients who reported on transient electrifying pain and heat sensation at the implantation site of the neuromodulator during MRI.

CONCLUSION

MRI scans in patients with an implanted InterStim II sacral neuromodulator and with the device being turned off seem to be safe, even if they involve body regions other than the head, at least with 1.5 Tesla.

Is there a role for sacral neuromodulation in patients with neurogenic lower urinary tract dysfunction?

PURPOSE

To review current literature regarding sacral neuromodulation (SNM) for neurogenic lower urinary tract dysfunction (NLUTD) focused on indications, barriers and latest technological developments.

MATERIAL AND METHODS

A PubMed database search was performed in April 2020, focusing on SNM and various neuro-urological conditions.

RESULTS

SNM has been increasingly indicated for lower urinary tract dysfunction (LUTD) in neuro-urological patients. Most studies are cases series with several methodological limitations and limited follow-up, lacking standardized definition for SNM clinical success. Most series focused on neurogenic overactive bladder in spinal cord injured (incomplete lesions) and multiple sclerosis patients. Barriers for applying this therapy in neurogenic LUTD were mainly related to magnetic resonance imaging incompatibility, size of the implantable pulse generator (IPG), and battery depletion. Newer technological advances have been made to address these limitations and will be widely available in the near future.

CONCLUSIONS

SNM seems a promising therapy for neurogenic LUTD in carefully selected patients with incomplete lesions. Further studies are still needed to define which subgroups of neurological patients benefit the most from this minimally invasive technique.

Intraspinal stimulation with a silicon-based 3D chronic microelectrode array for bladder voiding in cats

Objective.

Bladder dysfunction is a significant and largely unaddressed problem for people living with spinal cord injury (SCI). Intermittent catheterization does not provide volitional control of micturition and has numerous side effects. Targeted electrical microstimulation of the spinal cord has been previously explored for restoring such volitional control in the animal model of experimental SCI. Here, we continue the development of the intraspinal microstimulation array technology to evaluate its ability to provide more focused and reliable bladder control in the feline animal model.

Approach.

For the first time, a mechanically robust intraspinal multisite silicon array was built using novel microfabrication processes to provide custom-designed tip geometry and 3D electrode distribution. Long-term implantation was performed in eight spinally intact animals for a period up to 6 months, targeting the dorsal gray commissure area in the S2 sacral cord that is known to be involved in the coordination between the bladder detrusor and the external urethral sphincter.

Main results.

About one third of the electrode sites in the that area produced micturition-related responses. The effectiveness of stimulation was further evaluated in one of eight animals after spinal cord transection (SCT). We observed increased bladder responsiveness to stimulation starting at 1 month post-transection, possibly due to supraspinal disinhibition of the spinal circuitry and/or hypertrophy and hyperexcitability of the spinal bladder afferents.

Significance.

3D intraspinal microstimulation arrays can be chronically implanted and provide a beneficial effect on the bladder voiding in the intact spinal cord and after SCT. However, further studies are required to assess longer-term reliability and safety of the developed intraspinal microstimulation array prior to eventual human translation.

Evaluation of pre-operative bladder contractility as a predictor of improved response rate to a staged trial of sacral neuromodulation in patients with detrusor underactivity

PURPOSE

Sacral neuromodulation (SNM) is one of the few management options shown to improve outcomes in patients with detrusor underactivity (DU). This original research will investigate if preserved bladder contractility can predict a successful treatment with SNM.

METHODS

This is a retrospective study of a prospectively collected database of consecutive patients with DU, who had a staged SNM trial from January 2013 to December 2018, with a minimum of 12 months follow-up. The primary outcome was the success of stage 1 SNM trial.

RESULTS

In total, 69 patients with DU were followed. The median age was 67 [interquartile range (IQR) 74-55], median baseline bladder contractility index (BCI) 18 (IQR 67-0), and median post-void residual 200 mL (IQR 300-130). There were 35 patients (51%) that responded to a SNM trial. At a median follow-up of 23 months (IQR 39-12), three were removed for poor efficacy. In patients with detrusor acontractility (DAC), six responded (33%), compared to 29 patients (57%) with BCI > 0. This was statistically significant, p value 0.03. Younger age was also a predictive factor for SNM response, p value 0.02. There were no differences noted in those with gender, neurogenic history, previous pelvic surgery, diabetes, or pre-operative voiding history.

CONCLUSION

Our study showed that patients with preserved bladder contractility are more likely to respond to a trial of SNM compared with those that have DAC. Younger age was also predictive of SNM response. UDS is the only method to accurately identify DAC patients. This information will help in patient selection and pre-operative counselling.

Spinal cord stimulation for the restoration of bladder function after spinal cord injury

Spinal cord injury (SCI) results in the inability to empty the bladder voluntarily, and neurogenic detrusor overactivity (NDO) and detrusor sphincter dyssynergia (DSD) negatively impact both the health and quality of life of persons with SCI. Current approaches to treat bladder dysfunction in persons with SCI, including self-catheterisation and anticholinergic medications, are inadequate, and novel approaches are required to restore continence with increased bladder capacity, as well as to provide predictable and efficient on-demand voiding. Improvements in bladder function following SCI have been documented using a number of different modalities of spinal cord stimulation (SCS) in both persons with SCI and animal models, including SCS alone or SCS with concomitant activity-based training. Improvements include increased volitional voiding, voided volumes, bladder capacity, and quality of life, as well as decreases in NDO and DSD. Further, SCS is a well-developed therapy for chronic pain, and existing Food And Drug Administration (FDA)-approved devices provide a clear pathway to sustainable commercial availability and impact. However, the effective stimulation parameters and the appropriate timing and location of stimulation for SCS-mediated restoration of bladder function require further study, and studies are needed to determine underlying mechanisms of action.

Neurostimulation in neurogenic patients

PURPOSE OF REVIEW

To provide an overview of available electrical stimulation devices in neurogenic patients with lower urinary tract disease.

RECENT FINDINGS

It is advocated to do more studies in neurogenic patients as results seem promising and useful but most studies did not include neurogenic patients or neurogenic patients were not analyzed or reported separately. Most studies included a small heterogenous neurogenic group with multiple pathophysiologic origin focusing on effect of a treatment instead of results of a treatment in a specific neurogenic group. Neuromodulation or stimulation has the advantage that it acts on different organs, like bladder and bowel, so can treat neurogenic patients, who mostly suffer from multiple organ failure.

SUMMARY

Brindley procedure, sacral neuromodulation (SNM) and posterior tibial nerve stimulation (PTNS) are available for a while already. The Brindley procedure (including sacral anterior root stimulation in combination with a rhizotomy of posterior sacral roots) is developed for selected spinal cord injury patient with a complete spinal injury, and has shown results for many years in neurogenic patients. An alternative to the rhizotomy is not established yet. SNM and PTNS are other modalities that are used in nonneurogenic patients, but are not yet indicated and much studied in neurogenic patients.

Early sacral neuromodulation ameliorates urinary bladder function and structure in complete spinal cord injury minipigs

Aims

To determine the effects of early sacral neuromodulation (SNM) and pudendal neuromodulation (PNM) on lower urinary tract (LUT) function, minipigs with complete spinal cord injury (cSCI) were analyzed. SNM and PNM have been proposed as therapeutic approaches to improve bladder function, for example after cSCI. However, further evidence on efficacy is required before these methods can become clinical practice.

Methods

Eleven adults, female Göttingen minipigs with cSCI at vertebral level T11‐T12 were included: SNM (n = 4), PNM (n = 4), and SCI control (SCIC: n = 3). Tissue from six healthy minipigs was used for structural comparisons. Stimulation was started 1 week after cSCI. Awake urodynamics was performed on a weekly basis. After 16 weeks follow‐up, samples from the urinary bladder were taken for analyses.

Results

SNM improved bladder function with better capacities and lower detrusor pressures at voiding and avoided the emergence of detrusor sphincter dyssynergia (DSD). PNM and untreated SCI minipigs had less favorable outcomes with either DSD or constant urinary retention. Structural results revealed SCI‐typical fibrotic alterations in all cSCI minipigs. However, SNM showed a better‐balanced distribution of smooth muscle to connective tissue with a trend towards the reduced progression of bladder wall scarring.

Conclusion

Early SNM led to an avoidance of the emergence of DSD showing a more physiological bladder function during a 4 month follow‐up period after cSCI. This study might pave the way for the clinical continuation of early SNM for the treatment of neurogenic LUT dysfunction after SCI.

A Urodynamic Comparison of Neural Targets for Transcutaneous Electrical Stimulation to Acutely Suppress Detrusor Contractions Following Spinal Cord Injury

Objectives

To assess and compare the effect of transcutaneous Dorsal Genital Nerve Stimulation (DGNS), Tibial Nerve Stimulation (TNS), Sacral Nerve Stimulation (SNS), and Spinal Stimulation (SS) on Neurogenic Detrusor Overactivity (NDO) and bladder capacity in people with Spinal Cord Injuries (SCI).

Materials and Methods

Seven male participants with supra-sacral SCI were tested. Standard cystometry (CMG) was performed to assess bladder activity at baseline and with stimulation applied at each site. This was conducted over four separate sessions. All stimulation was monophasic, 15 Hz, 200 μS pulses and applied at maximum tolerable amplitude. Results were analysed against individual control results from within the same session.

Results

Dorsal Genital Nerve Stimulation increased bladder capacity by 153 ± 146 ml (p = 0.016) or 117 ± 201%. DGNS, TNS and SNS all increased the volume held following the first reflex contraction, by 161 ± 175, 46 ± 62, and 34 ± 33 ml (p = 0.016, p = 0.031, p = 0.016), respectively. SS results showed small reduction of 33 ± 26 ml (p = 0.063) from baseline bladder capacity in five participants. Maximum Detrusor Pressure before leakage was increased during TNS, by 10 ± 13 cmH₂O (p = 0.031) but was unchanged during stimulation of other sites. DGNS only was able to suppress at least one detrusor contraction in five participants and reduced first peak detrusor pressure below 40 cmH₂O in these 5. Continuous TNS, SNS, and SS produced non-significant changes in bladder capacity from baseline, comparable to conditional stimulation. Increase in bladder capacity correlated with stimulation amplitude for DGNS but not TNS, SNS or SS.

Conclusion

In this pilot study DGNS acutely suppressed detrusor contractions and increased bladder capacity whereas TNS, SNS, and SS did not. This is the first within individual comparison of surface stimulation sites for management of NDO in SCI individuals.

Guideline for the management of pre-, intra-, and postpartum care of women with a spinal cord injury

The German Association of the Scientific Medical Societies guideline for pregnancy, childbirth, and puerperium in women with a spinal cord injury (SCI) addresses a range of topics from the desire to have a child to different stages of pregnancy and birth. Given that a generally accessible and evidence-based presentation of this complex issue does not yet exist, this new guideline contributes to the standardization of gynecological, obstetric, and maternal care of women with SCI. This guideline aims to provide practice-oriented support for the care and counseling of women in the pre-, intra-, and postpartum periods; to close identified gaps in medical care; foster collaboration among clinicians of relevant disciplines; and inspire research.

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.

Protocol for a randomized clinical trial investigating early sacral nerve stimulation as an adjunct to standard neurogenic bladder management following acute spinal cord injury

Background

Neurogenic bladder (NGB) dysfunction after spinal cord injury (SCI) is generally irreversible. Preliminary animal and human studies have suggested that initiation of sacral neuromodulation (SNM) immediately following SCI can prevent neurogenic detrusor overactivity and preserve bladder capacity and compliance. We designed a multicenter randomized clinical trial to evaluate the effectiveness of early SNM after acute SCI.

Methods/Design

The scientific protocol comprises a multi-site, randomized, non-blinded clinical trial. Sixty acute, acquired SCI patients (30 per arm) will be randomized within 12 weeks of injury. All participants will receive standard care for NGB including anticholinergic medications and usual bladder management strategies. Those randomized to intervention will undergo surgical implantation of the Medtronic PrimeAdvanced Surescan 97,702 Neurostimulator with bilateral tined leads along the S3 nerve root in a single-stage procedure. All patients will undergo fluoroscopic urodynamic testing at study enrollment, 3 months, and 1-year post randomization. The primary outcome will be changes in urodynamic maximum cystometric capacity at 1-year. After accounting for a 15% loss to follow-up, we expect 25 evaluable patients per arm (50 total), which will allow detection of a 38% treatment effect. This corresponds to an 84 mL difference in bladder capacity (80% power at a 5% significance level). Additional parameters will be assessed every 3 months with validated SCI-Quality of Life questionnaires and 3-day voiding diaries with pad-weight testing. Quantified secondary outcomes include: patient reported QoL, number of daily catheterizations, incontinence episodes, average catheterization volume, detrusor compliance, presence of urodynamic detrusor overactivity and important clinical outcomes including: hospitalizations, number of symptomatic urinary tract infections, need for further interventions, and bowel and erectile function.

Discussion

This research protocol is multi-centered, drawing participants from large referral centers for SCI and has the potential to increase options for bladder management after SCI and add to our knowledge about neuroplasticity in the acute SCI patient.

Trial registration

ClinicalTrials.gov #NCT03083366 1/27/2017.

Translating promising strategies for bowel and bladder management in spinal cord injury

Loss of control over voiding following spinal cord injury (SCI) impacts autonomy, participation and dignity, and can cause life-threatening complications. The importance of SCI bowel and bladder dysfunction warrants significantly more attention from researchers in the field. To address this gap, key SCI clinicians, researchers, government and private funding organizations met to share knowledge and examine emerging approaches. This report reviews recommendations from this effort to identify and prioritize near-term treatment, investigational and translational approaches to addressing the pressing needs of people with SCI.

Role of sacral neuromodulation in modern urogynaecology practice: a review of recent literature

Sacral neuromodulation (SNM) offers promise in the therapy of many pelvic floor disorders. This innovative treatment has slowly gained popularity. A review of recent literature is presented in relation to its efficacy and complications in various pelvic floor conditions: overactive bladder and urge urinary incontinence, chronic urinary retention, painful bladder syndrome, pelvic pain and double incontinence. It is a minimally invasive, completely reversible safe procedure with good long-term outcomes. However, the treatment is costly, the revision rate is high and patients require life-long follow-up. SNM should always be considered in suitable patients before offering bladder augmentation procedures or urinary diversion or permanent catheterization for bladder dysfunction. SNM should also be considered in patients with double incontinence, after discussion in a urogynaecology/colorectal multidisciplinary team.

Peripheral and Sacral Neuromodulation in the Treatment of Neurogenic Lower Urinary Tract Dysfunction

Sacral and peripheral neuromodulation are minimally invasive surgical procedures that are third-line therapy options for the treatment of patients with idiopathic overactive bladder syndrome. There has been interest in their efficacy in the management of neurogenic lower urinary tract dysfunction (NLUTD). Contemporary data suggest promising outcomes for urinary and bowel symptoms in carefully selected patients with spinal cord injury and/or multiple sclerosis. This article reviews the current literature regarding urinary and bowel outcomes in patients with NLUTD and also discusses contemporary studies that suggest that treatment during particular stages of neurologic injury may prevent long-term urinary sequelae.

Neuromodulation in neurogenic bladder

While neuromodulation is a well-established treatment option for patients with non-neurogenic overactive bladder and urinary retention, its applicability to the neurogenic bladder population has only recently been examined more in depth. In this article we will discuss the outcomes, contraindications, and special considerations of sacral and percutaneous tibial nerve stimulation (PTNS) in patients with neurogenic lower urinary tract dysfunction.