Sacral Neuromodulation for Refractory Lower Urinary Tract Dysfunction: Results of a Nationwide Registry in Switzerland

Spinal Cord Stimulation for Intractable Visceral Pain Originating from the Pelvic and Abdominal Region: A Narrative Review on a Possible New Indication for Patients with Therapy-Resistant Pain

Aim

Visceral pain, characterized by pain that is diffuse and challenging to localize, occurs frequently and is difficult to treat. In cases where the pain becomes intractable despite optimal medical management, it can affect patients' Quality of Life (QoL). Spinal Cord Stimulation (SCS) has emerged as a potential solution for intractable visceral pain.

Purpose

In this narrative review, we collected all evidence regarding the efficacy of SCS for visceral pain across various underlying conditions.

Methods

A comprehensive literature search was conducted in PubMed, Embase, and Web of Science in which articles published from October 1st, 1963 up to March 7th, 2023 were identified.

Results

Seventy articles were included in this review of which most were retrospective cohort studies, case series and case reports. The studies, often with a small number of participants, reported on SCS for chronic pancreatitis, anorectal pain and bowel disorders, gynaecological diagnoses, visceral pelvic pain, urological disorders and finally general visceral pain. They found positive effects on pain and/or symptom relief, opioid consumption, anxiety and depression and QoL. Complications occurred frequently but were often minor and reversible.

Conclusion

Better screening and selection criteria need to be established to optimally evaluate eligible patients who might benefit from SCS. A positive outcome of a sympathetic nerve block appears to be a potential indicator of SCS effectiveness. Additionally, women receiving SCS for endometriosis had a better outcome compared to other indications. Finally, SCS could also relief functional symptoms such as voiding problems and gastroparesis. Complications could often be resolved with revision surgery. Since SCS is expensive and not always covered by standard health insurance, the incorporation of cost-analyses is recommended. In order to establish a comprehensive treatment plan, including selection criteria for SCS, rigorous prospective, possibly randomized and controlled studies that are diagnosis-oriented, with substantial follow-up and adequate sample sizes, are needed.

Neuromodulation for the management of chronic pelvic pain syndromes: A systematic review

BACKGROUND

Chronic pelvic pain is a burdensome condition that involves multiple medical sub-specialties and is often difficult to treat. Sacral stimulation for functional bladder disease has been well established, but little large-scale evidence exists regarding utilization of other neuromodulation techniques to treat chronic pelvic pain. Emerging evidence does suggest that neuromodulation is a promising treatment, and we aim to characterize the use and efficacy of such techniques for treating chronic pelvic pain syndromes.

MATERIALS AND METHODS

A systematic review of the literature demonstrating the treatment of chronic pelvic pain syndromes with neuromodulation. Abstracts were reviewed and selected for inclusion, including case series, prospective studies, and randomized controlled trials (RCTs). Case studies and publications in abstract only were not included. The reporting for this systematic review follows Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The literature search was performed using MEDLINE, Embase, Cochrane Library, PubMed, CINAHL, and Scopus.

RESULTS

A total of 50 studies were included in this review, three of which were randomized controlled trials, and the remaining were prospective and retrospective case series. The range of pelvic pain conditions treated included interstitial cystitis, peripheral neuralgia, pudendal neuralgia, gastrointestinal pain, urogenital pain, sacroiliac joint pain, and visceral chronic pelvic pain. We reported on outcomes involving pain, functionality, psychosocial improvement, and medication reduction.

CONCLUSIONS

Neuromodulation is a growing treatment for various chronic pain syndromes. Peripheral nerve stimulation was the least studied form of stimulation. Posterior tibial nerve stimulation appears to offer short-term benefit, but long-term results are challenging. Sacral nerve stimulation is established for use in functional bladder syndromes and appears to offer pain improvement in these patients as well. Dorsal root ganglion stimulation and spinal cord stimulation have been used for a variety of conditions with promising results. Further studies of homogeneous patient populations are necessary before strong recommendations can be made at this time, although pooled analysis may also be impactful.

Sacral neuromodulation in the management of chronic pelvic pain: A systematic review and meta-analysis

INTRODUCTION

Sacral neuromodulation (SNM) is a treatment approved for use in several conditions including refractory overactive bladder (OAB) and voiding dysfunction. Chronic pelvic pain (CPP) is a debilitating condition for which treatment is often challenging. SNM shows promising effect in patients with refractory CPP. However, there is a lack of clear evidence, especially in long-term outcomes. This systematic review will assess outcomes of SNM for treating CPP.

METHODS

A systematic search of MEDLINE, Embase, Cochrane Central and clinical trial databases was completed from database inception until January 14, 2022. Studies using original data investigating SNM in an adult population with CPP which recorded pre and posttreatment pain scores were selected. Primary outcome was numerical change in pain score. Secondary outcomes were quality of life assessment and change in medication use and all-time complications of SNM. Risk of bias was assessed using the Newcastle Ottawa Tool for cohort studies.

RESULTS

Twenty-six of 1026 identified articles were selected evaluating 853 patients with CPP. The implantation rate after test-phase success was 64.3%. Significant improvement of pain scores was reported in 13 studies; three studies reported no significant change. WMD in pain scores on a 10-point scale was -4.64 (95% confidence interval [CI] = -5.32 to -3.95, p < 0.00001) across 20 studies which were quantitatively synthesized: effects were maintained at long-term follow-up. Mean follow-up was 42.5 months (0-59). Quality of life was measured by RAND SF-36 and EQ-5D questionnaires and all studies reported improvement in quality of life. One hundred and eighty-nine complications were reported in 1555 patients (Clavien-Dindo Grade I-IIIb). Risk of bias ranged from low to high risk. Studies were case series and bias stemmed from selection bias and loss to follow-up.

CONCLUSION

Sacral Neuromodulation is a reasonably effective treatment of Chronic Pelvic Pain and significantly reduces pain and increases patients' quality of life with immediate to long-term effects.

Neuromodulation for Management of Chronic Pelvic Pain: A Comprehensive Review

INTRODUCTION

Chronic pelvic pain (CPP) is a symptom that derives from a complex group of heterogeneous pathologies of the pelvic organs. The aim of this study was to review the available evidence on efficacy of neuromodulatory modalities including sacral neuromodulation, dorsal root ganglion stimulation, dorsal column neuromodulation, and pudendal nerve stimulation.

METHODS

This narrative review focuses on updated information on neuromodulation for management of chronic pelvic pain. In 2022, we searched English-language studies on neuromodulation, pelvic pain, and chronic pain in a comprehensive search. We searched the following databases: PubMed, Medline, SciHub, Cochrane Database of Systematic Reviews, and Google Scholar. We used the following combinations of keywords: neuromodulation, pelvic pain, chronic pain, chronic pelvic pain, pelvic pain treatment. We tried to include as many recent manuscripts as possible (within the last 3 years) but also included papers older than 3 years if they were particularly relevant to our topic. We also attempted to search for, use, and cite primary manuscripts whenever possible.

RESULTS

CPP is a challenging entity to treat because of diagnostic inconsistencies and limited evidence for therapeutic modalities. Our review found evidence suggestive of benefit for all modalities reviewed but the data was of overall low quality with numerous limitations. The literature highlights a lack of randomized controlled trials for neuromodulatory therapies but suggests a growing role for such techniques in treating refractory chronic pelvic pain syndrome (CPPS).

CONCLUSIONS

This review explores the available evidence on efficacy of neuromodulatory modalities for CPPS and contextualizes the results with information about the type of neuromodulation, lead location and waveform, pain outcomes and assessment timepoints, and reported adverse effects.

Sacral Neuromodulation for Neurogenic Lower Urinary Tract Dysfunction

BACKGROUND: Neurogenic lower urinary tract dysfunction (NLUTD) is a highly prevalent and disabling condition; nevertheless, standard treatments often remain unsatisfactory. Sacral neuromodulation (SNM) is a well-established therapy for non-NLUTD, but there is a lack of randomized controlled trials to show benefit in patients with NLUTD. METHODS: For this sham-controlled, double-blind, multicenter trial, patients with refractory NLUTD (and intended SNM) were recruited at four Swiss SNM referral centers. After lead placement into the sacral foramina S3 (rarely, S4), all participants underwent SNM testing. If successful (≥50% improvement in key bladder diary variables), the neurostimulator was implanted for permanent stimulation. For 2 months, neuromodulation was optimized using subsensory stimulation with individually adjusted parameters. Thereafter, the neurostimulator remained on or was switched off (1:1 random allocation to group SNM ON or SNM OFF, respectively) for 2 months, followed by a neurourologic reevaluation. The primary outcome was success, as defined above, of SNM compared with baseline. RESULTS: Of 124 patients undergoing SNM testing, 65 (52%) had successfully improved lower urinary tract function. Of these, 60 patients (median age, 49.5 years; 43 women) were randomly assigned to the intervention. After 2 months of intervention, the SNM ON group demonstrated a success rate of 76%. In the SNM OFF group, 42% of patients showed sustained SNM effects despite their neurostimulator being switched off during the last 2 months (odds ratio, 4.35; 95% confidence interval, 1.43 to 13.21; P=0.009). During the entire study period, there were 11 adverse events (6 dropouts; no dropouts during the intervention phase). CONCLUSIONS: SNM effectively corrected refractory NLUTD in the short term in well-selected neurologic patients. (Funded by the Swiss National Science Foundation, Vontobel–Stiftung, Gottfried und Julia Bangerter–Rhyner Stiftung, Dr. Urs Mühlebach, and the Swiss Continence Foundation; ClinicalTrials.gov number, NCT02165774.)

Predictive Factors in Sacral Neuromodulation: A Systematic Review

INTRODUCTION

Sacral neuromodulation (SNM) is an effective treatment in patients with overactive bladder syndrome or nonobstructive urinary retention when conservative treatment fails. Several factors that could impact outcome with SNM have been studied. This systematic review investigated these predictive factors and their relevance for clinical practice.

METHODS

Systematic review according to the PRISMA guidelines was conducted. This review is registered in the PROSPERO register (CRD42015016256).

RESULTS

Seventy-eight studies (of which 11 abstracts) were included. Females, younger patients, and a tined lead procedure tend to be predictive in successful SNM outcome. Factors that did not influence SNM outcome were prior back surgery, surgery for stress urinary incontinence, affective symptoms, and duration of complaints. Reduced detrusor contractility is associated with a lower success rate. The level of evidence of most studies (graded according to the Centre for Evidence-Based Medicine) was 3b.

CONCLUSION

Even though this systematic review investigated predictive factors (gender, age, type of procedure, type of lead, and detrusor contractility), no general consensus on predictive factors could be made. Most studies are small, retrospective, and involve a heterogeneous population. Therefore, prospective research in larger specific patient groups remains necessary to find predictors of SNM outcome.

[Functional results and satisfaction in 44 patients after implantation of a NS3-type sacral neurostimulator for refractory idiopathic overactive bladder followed at 43 months, single-center series]

OBJECTIVES

Sacred neuromodulation (SNM) has been used in France since 1997 for the management of non-neurogenic urinary disorders that do not respond to first-line pharmacological treatment. The aim of this study is to analyze the clinical efficacy and satisfaction of patients with refractory idiopathic overactive bladder (OAB) treated with SNM.

METHODS

This single-center retrospective series included 59 patients with refractory OAB of idiopathic origin and eligible for the SNM between January 2010 and December 2017. Demographic data, history of pelvic surgery, complications according to Clavien-Dindo classification, as well as revision and explantation rates were collected. All the patients included underwent a test phase. Therapeutic success for the test phase and definitive implantation was defined by≥50% improvement. Satisfaction was a secondary criteria.

RESULTS

Of the 59 patients tested for SNM, 44 patients had a permanent implantation, of which 36 (82%) were women and 8 (12%) were men. The median age of the study was 55 years old. The median follow-up was 43 months [21,2-66,5]. All of the patients had an idiopathic refractory OAB. The median time between test and final implantation was 28 days [18-35]. The success rate for all patients tested was 60% (34/59). In patients implanted, 34 patients (77%) had clinical improvement. Adverse events had to be managed including multiple re-parameterizations (n=13), device revision (n=16), or even device implantation (n=8). The satisfaction rate was 82% (36/44).

CONCLUSION

With a median follow-up of 43 months, this retrospective study on NMS shows the efficacy of second-line SNM for idiopathic OAB. This technique remains minimally invasive but with significant adverse events when informing our patients.

LEVEL OF EVIDENCE

3.

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.

The Management of Lower Urinary Tract Dysfunction in Multiple Sclerosis

PURPOSE OF REVIEW

Multiple sclerosis (MS) is the most frequent neuroinflammatory disease of the central nervous system and is commonly associated with lower urinary tract (LUT) dysfunction. As a consequence, health-related quality of life is often impaired and the upper urinary tract might be at risk for damage. The aim of this review is to give an overview of current treatment options for LUT dysfunction in patients with MS.

RECENT FINDINGS

The treatment is tailored to the type of dysfunction-storage or voiding dysfunction-beginning with conservative treatment options and ending with invasive therapies and surgery. Additionally, alternative options, e.g., different intravesical therapies or cannabinoids, have been evaluated in recent years with promising results. Current available therapies offer different possible treatments for LUT dysfunction in patients with MS. They address either voiding or storage dysfunction and therefore ameliorate LUT symptoms improve quality of life and protect the upper urinary tract.

Long-Term Functional Outcomes of S3 Sacral Neuromodulation for the Treatment of Idiopathic Overactive Bladder

OBJECTIVES

To assess the long-term functional outcomes of sacral neuromodulation (SNM) in the treatment of refractory idiopathic overactive bladder (IOAB) and to determine predictive factors for success.

MATERIALS AND METHODS

To obtain long-term data, all consecutive patients suffering from IOAB and treated by SNM at a single tertiary care center between December 1996 and December 2004 were included. Data regarding patient demographics, past medical, and surgical history, bladder diary, complications as well as device revision and removal rates were collected. Success was defined as an improvement ≥ 50% of any clinical parameter.

RESULTS

Overall, 34 patients, with a median age of 57.8 years (IQR 44.8-65.7) were included. Immediately after definitive implantation, 2 (6%) patients were lost to follow-up. After a median follow-up of 9.7 years (IQR 4.7-12.0), SNM was considered successful in 20 (63%) patients. Mean amount of protections used per 24 hours significantly decreased (4.1 preoperatively vs. 1.8 at the last follow-up visit, p = 0.02). Devices were removed in 2 (6%) patients due to pain and lack of efficacy. Twenty-two revision surgeries were performed in 15 (47%) patients. First revision surgery occurred after a mean of 6.2 years (± 3.1). Revision surgeries were mainly performed for end of battery life/device dysfunction (n = 18, 82%). No significant predictor for success was identified.

CONCLUSIONS

With a median follow-up time of 9.7 years, this retrospective SNM study reports a 63% efficacy rate (≥ 50% improvement) for the treatment of refractory IOAB. Moreover, it is a well-tolerated and minimally invasive therapy.

Sacral Neuromodulation for Refractory Bladder Pain Syndrome/Interstitial Cystitis: a Global Systematic Review and Meta-analysis

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a common debilitating disease and there has not been consistently effective treatment. We aimed to evaluate all available literature regarding the efficacy and safety of sacral neuromodulation (SNM) for refractory BPS/IC. A comprehensive search of Pubmed, Web of Science and Cochrane Library through May 2016 was conducted. A total of 17 studies enrolling 583 patients were identified. Pooled analyses demonstrated that SNM was associated with great reduction in pelvic pain (weighted mean difference [WMD] −3.99; 95% confidence interval [CI] −5.22 to −2.76; p < 0.00001), Interstitial Cystitis Problem and Symptom Index scores (WMD −6.34; 95% CI −9.57 to −3.10; p = 0.0001; and WMD −7.17; 95% CI −9.90 to −4.45; p < 0.00001, respectively), daytime frequency (WMD −7.45; 95% CI −9.68 to −5.22; p < 0.00001), nocturia (WMD −3.01; 95% CI −3.56 to −2.45; p < 0.00001), voids per 24 hours (WMD −9.32; 95% CI −10.90 to −7.74; p < 0.00001) and urgency (WMD −1.08; 95% CI −1.79 to −0.37; p = 0.003) as well as significant improvement in average voided volume (WMD 95.16 ml; 95% CI 63.64 to 126.69; p < 0.0001). The pooled treatment success rate was 84% (95% CI 76% to 91%). SNM-related adverse events were minimal. Current evidence indicates that SNM might be effective and safe for treating refractory BPS/IC.

Five-Year Followup Results of a Prospective, Multicenter Study of Patients with Overactive Bladder Treated with Sacral Neuromodulation

PURPOSE

We evaluated the therapeutic success rate, changes in quality of life and safety of sacral neuromodulation 5 years after InterStim™ implantation. Included in study were subjects with bothersome symptoms of overactive bladder, including urinary urge incontinence and/or urgency-frequency, in whom at least 1 anticholinergic medication failed and 1 medication had not been tried.

MATERIALS AND METHODS

Therapeutic success was defined as a urinary urge incontinence or urgency-frequency response of 50% or greater improvement in average leaks or voids per day, or return to normal voiding, defined as fewer than 8 voids per day. Quality of life was evaluated by ICIQ-OABqol (International Consultation on Incontinence Modular Questionnaire). Safety was evaluated through adverse events.

RESULTS

Of the 340 subjects who completed the test stimulation 272 had an implant, of whom 91% were female. Mean age was 57 years. At baseline 202 subjects with urinary urge incontinence had a mean ± SD of 3.1 ± 2.7 leaks per day and 189 with urgency-frequency had a mean of 12.6 ± 4.5 voids per day. The 5-year therapeutic success rate was 67% (95% CI 60-74) using modified completers analysis and 82% (95% CI 76-88) using completers analysis. Subjects with urinary urge incontinence had a mean reduction from baseline of 2.0 ± 2.2 leaks per day and subjects with urgency-frequency had a mean reduction of 5.4 ± 4.3 voids per day (each completers analysis p <0.0001). Subjects showed improvement in all ICIQ-OABqol measures (p <0.0001). The most common device related adverse events were an undesirable change in stimulation in 60 of the 272 subjects (22%), implant site pain in 40 (15%) and therapeutic product ineffectiveness in 36 (13%).

CONCLUSIONS

This multicenter study shows that sacral neuromodulation had sustained efficacy and quality of life improvements, and an acceptable safety profile through 5 years in subjects with overactive bladder.

Impact of ao-dake-humi, Japanese traditional bamboo foot stimulator, on lower urinary tract symptoms, constipation and hypersensitivity to cold: a single-arm prospective pilot study

Background

Ao-dake-humi is a traditional Japanese bamboo foot stimulator consisting of a half-pipe-shaped step made of bamboo used to stimulate the foot by stepping on it, and is commonly used to promote general health among the elderly in Japan. However, its efficacy has not been reported in the scientific literature. This study was performed to investigate the role of ao-dake-humi focusing on lower urinary tract symptoms (LUTS), constipation, and hypersensitivity to cold (HC).

Methods

Participants with LUTS, constipation, or HC were enrolled in this study. Ao-dake-humi was used twice a day for 28 days. Before and 28 days after starting ao-dake-humi use, international prostate symptom score (IPSS), quality-of-life (QoL) score, and overactive bladder symptom score (OABSS) were measured to evaluate the efficacy of ao-dake-humi on LUTS. To evaluate the objective efficacy of ao-dake-humi on LUTS, a frequency-volume chart (FVC) was plotted in LUTS patients for 3 days. A visual analogue scale (VAS) was used to evaluate the efficacy of ao-dake-humi on constipation (VAS-constipation) and HC (VAS-HC) in the participants with constipation or HC.

Results

A total of 24 participants were enrolled in this study. Twenty-one participants had LUTS, 11 had constipation, and 17 participants had HC. IPSS, especially storage-subscore, QoL score and OABSS, decreased significantly after use of ao-dake-humi. The use of ao-dake-humi increased maximal bladder capacity, resulting in a significant decrease in urinary frequency as determined from the FVC. In accordance with the results of VAS-constipation and VAS-HC, both constipation and HC were significantly relieved after ao-dake-humi use.

Conclusion

The results of this prospective pilot study indicated that ao-dake-humi is safe and has therapeutic efficacy in cases of LUTS, constipation and HC. The possibility of using ao-dake-humi as physical neuromodulation therapy was shown in the management of LUTS, constipation and HC.

Trial registration

UMIN000019333 (UMIN-CTR, Registered October-15-2015) retrospectively registered.

Electronic approaches to restoration of sight

Retinal prostheses are a promising means for restoring sight to patients blinded by the gradual atrophy of photoreceptors due to retinal degeneration. They are designed to reintroduce information into the visual system by electrically stimulating surviving neurons in the retina. This review outlines the concepts and technologies behind two major approaches to retinal prosthetics: epiretinal and subretinal. We describe how the visual system responds to electrical stimulation. We highlight major differences between direct encoding of the retinal output with epiretinal stimulation, and network-mediated response with subretinal stimulation. We summarize results of pre-clinical evaluation of prosthetic visual functions in- and ex vivo, as well as the outcomes of current clinical trials of various retinal implants. We also briefly review alternative, non-electronic, approaches to restoration of sight to the blind, and conclude by suggesting some perspectives for future advancement in the field.

Photovoltaic Pixels for Neural Stimulation: Circuit Models and Performance

Photovoltaic conversion of pulsed light into pulsed electric current enables optically-activated neural stimulation with miniature wireless implants. In photovoltaic retinal prostheses, patterns of near-infrared light projected from video goggles onto subretinal arrays of photovoltaic pixels are converted into patterns of current to stimulate the inner retinal neurons. We describe a model of these devices and evaluate the performance of photovoltaic circuits, including the electrode-electrolyte interface. Characteristics of the electrodes measured in saline with various voltages, pulse durations, and polarities were modeled as voltage-dependent capacitances and Faradaic resistances. The resulting mathematical model of the circuit yielded dynamics of the electric current generated by the photovoltaic pixels illuminated by pulsed light. Voltages measured in saline with a pipette electrode above the pixel closely matched results of the model. Using the circuit model, our pixel design was optimized for maximum charge injection under various lighting conditions and for different stimulation thresholds. To speed discharge of the electrodes between the pulses of light, a shunt resistor was introduced and optimized for high frequency stimulation.

Conjoint Urological Society of Australia and New Zealand (USANZ) and Urogynaecological Society of Australasia (UGSA) Guidelines on the management of adult non-neurogenic overactive bladder

Due to the myriad of treatment options available and the potential increase in the number of patients afflicted with overactive bladder (OAB) who will require treatment, the Female Urology Special Advisory Group (FUSAG) of the Urological Society of Australia and New Zealand (USANZ), in conjunction with the Urogynaecological Society of Australasia (UGSA), see the need to move forward and set up management guidelines for physicians who may encounter or have a special interest in the treatment of this condition. These guidelines, by utilising and recommending evidence-based data, will hopefully assist in the diagnosis, clinical assessment, and optimisation of treatment efficacy. They are divided into three sections: Diagnosis and Clinical Assessment, Conservative Management, and Surgical Management. These guidelines will also bring Australia and New Zealand in line with other regions of the world where guidelines have been established, such as the American Urological Association, European Association of Urology, International Consultation on Incontinence, and the National Institute for Health and Care Excellence guidelines of the UK.

Inhibitory Effect and Possible Mechanism of Intraurethral Stimulation on Overactive Bladder in Female Rats

Purpose:

To investigate the inhibitory effect and possible mechanism of intraurethral stimulation on overactive bladder (OAB) induced by acetic acid irritation.

Methods:

Cystometry was performed in 13 urethane-anesthetized female rats. Intravesical infusion of 0.5% acetic acid was used to irritate the bladder and induce OAB. Multiple cystometrograms were performed with mirabegron, continuous stimulation, mirabegron plus continuous stimulation, and β3-adrenoceptor antagonist plus continuous stimulation to determine the mechanism underlying the inhibitory effect by intraurethral stimulation.

Results:

Infusion of acetic acid significantly decreased bladder capacity. Intraurethral stimulation at 2.5 Hz plus mirabegron significantly increased bladder capacity and decreased the nonvoiding contraction count. The changes were strongly inhibited after the β3-adrenoceptor antagonist was administered.

Conclusions:

Activation of urethral afferent nerves can reverse OAB, which activates C-fiber afferent nerves. This animal study indicates that intraurethral stimulation may interfere with OAB through hypogastric nerve activation and pudendal nerve neuromodulation.

Protocol for a randomized, placebo-controlled, double-blind clinical trial investigating sacral neuromodulation for neurogenic lower urinary tract dysfunction

BACKGROUND

Sacral neuromodulation has become a well-established and widely accepted treatment for refractory non-neurogenic lower urinary tract dysfunction, but its value in patients with a neurological cause is unclear. Although there is evidence indicating that sacral neuromodulation may be effective and safe for treating neurogenic lower urinary tract dysfunction, the number of investigated patients is low and there is a lack of randomized controlled trials.

METHODS AND DESIGN

This study is a prospective, randomized, placebo-controlled, double-blind multicenter trial including 4 sacral neuromodulation referral centers in Switzerland. Patients with refractory neurogenic lower urinary tract dysfunction are enrolled. After minimally invasive bilateral tined lead placement into the sacral foramina S3 and/or S4, patients undergo prolonged sacral neuromodulation testing for 3-6 weeks. In case of successful (defined as improvement of at least 50% in key bladder diary variables (i.e. number of voids and/or number of leakages, post void residual) compared to baseline values) prolonged sacral neuromodulation testing, the neuromodulator is implanted in the upper buttock. After a 2 months post-implantation phase when the neuromodulator is turned ON to optimize the effectiveness of neuromodulation using sub-sensory threshold stimulation, the patients are randomized in a 1:1 allocation in sacral neuromodulation ON or OFF. At the end of the 2 months double-blind sacral neuromodulation phase, the patients have a neuro-urological re-evaluation, unblinding takes place, and the neuromodulator is turned ON in all patients. The primary outcome measure is success of sacral neuromodulation, secondary outcome measures are adverse events, urodynamic parameters, questionnaires, and costs of sacral neuromodulation.

DISCUSSION

It is of utmost importance to know whether the minimally invasive and completely reversible sacral neuromodulation would be a valuable treatment option for patients with refractory neurogenic lower urinary tract dysfunction. If this type of treatment is effective in the neurological population, it would revolutionize the management of neurogenic lower urinary tract dysfunction.

TRIAL REGISTRATION

TRIAL REGISTRATION NUMBER

http://www.clinicaltrials.gov; Identifier: NCT02165774.

Tined lead versus percutaneous nerve evaluation for sacral nerve stimulator assessment

Purpose:

We compared the outcomes of percutaneous nerve evaluation (PNE) with first-stage tined lead placement (FSTLP) for the testing phase of sacral nerve neuromodulation (SNM), and we assessed the outcomes of these two techniques following implantation of a (second-stage) permanent sacral nerve stimulator (SNS).

Methods:

Seventy consecutive patients had either PNE ( n = 35) or FSTLP ( n = 35) evaluation, and conversion to a permanent SNS implant according to response. Primary outcomes were assessed using frequency-volume charts, pad testing, ICIQ/EQ5D questionnaires and global health perception visual analogue scale (VAS). Success was considered if they achieved greater than 50% improvement in their urinary symptoms. Success and failure rates were compared during the test phase and after implantation of the SNS.

Results:

Mean follow-up for the FSTLP group was 14 months (nine to 20) and for the PNE group was 22 months (eight to 27). Sixteen (46%) of the PNE tests and 20 (57%) of the FSTLP patients were converted to permanent implant. A significant correlation was noted between patients’ general health (VAS score) and a successful test phase ( r = 0.297, p = 0.013). Eighteen of 19 (95%) of tined lead patients have successful SNS implants, whereas five of 16 (31%) of PNE evaluations failed to convert test efficacy to the permanent SNS implant ( p = 0.042). Furthermore, two of PNE-SNS patients were successfully salvaged by the implantation of a second tined lead.

Conclusions:

FSTLP-SNS has a significantly higher success rate than PNE-SNS in converting the test phase to SNS implantation. This may be due in part to difficulties retaining accurate lead placement with the two-lead (PNE-SNS) approach. These findings have important cost and logistical implications for SNS services.

Male incontinence: onabotulinum toxin A and sacral nerve stimulation

PURPOSE OF REVIEW

Overactive bladder affects 10-12% of men, of which 13% are refractory to medical therapy and seek second-line treatment. This places a substantial clinical and economic burden on the National Health Service United Kingdom.

RECENT FINDINGS

This review identifies current evidence for the use of onabotulinum toxin A and sacral nerve neuromodulation for the treatment of overactive bladder in patients who do not respond to optimal medical treatment. Posterior tibial nerve stimulation is not covered here. Clinical and financial implications of the treatments are reviewed.

SUMMARY

The focus will remain on recently published evidence, which may be useful to clinicians managing refractory patients.

Understanding the dissemination of sacral neuromodulation

OBJECTIVES

To assess trends in the use of sacral neuromodulation and to measure the magnitude of variation in its use across geographic regions.

METHODS

We used the State Ambulatory Surgery Database (SASD) from 2002 to 2009 from Florida to identify patients implanted with a neuromodulator. Age- and gender-adjusted rates of implantation were calculated by year and by geographic region, defined by the Hospital Service Area. The coefficient of variation was estimated to quantify the magnitude of variation for different time periods.

RESULTS

Adjusted rates of sacral neuromodulation increased significantly from 1.1 per 100,000 population in 2002 to 10.4 per 100,000 population in 2009. The majority of cases were performed for overactive bladder. There was a very large amount of geographic variation in rates of these procedures as evidenced by the high coefficients of variation: 1.67 (2002 and 2003), 1.70 (2004 and 2005), 1.49 (2006 and 2007), and 1.05 (2008 and 2009).

CONCLUSIONS

Rates of sacral neuromodulation have increased dramatically over the past decade. However, these rates of utilization are highly variable across regions, with some regions performing large numbers of these procedures and other regions performing few to no procedures. This range in practice patterns may reflect medical uncertainty surrounding the role of this procedure.

Efficacy of sacral neuromodulation in treating chronic pain related to painful bladder syndrome/interstitial cystitis in adults

OBJECTIVE

The objective of this review is to evaluate the efficacy and safety of sacral neuromodulation in treating chronic pelvic pain related to Painful bladder syndrome/Interstitial-cystitis.

DESIGN

The databases searched were MEDLINE and EMBASE [1950- Nov 2011]. Additional searches were performed on the Cochrane Database of Systematic reviews (CDSR), Scopus, CINAHL, BIOSIS, The Cochrane controlled trials register, the science citation index, TRIP DATABASE.

RESULTS

Overall 70.8% or 170/244 patients were successful at the trial stage. The only randomized controlled trial reported a decrease in Visual analogue pain scores of 49% (7.9 to 4.0) for sacral nerve stimulation [SNS] and 29%(4.5 to 3.2) for pudendal nerve stimulation [PNS] at 6 months follow up. Nine observational studies reported a decrease in pain scores/decrease in pain medications at long term follow up following permanent sacral neuromodulation. One study showed an 80% improvement in Global response assessment score.

CONCLUSION

The results from the randomised controlled trial and case series/case reports demonstrate a reduction of pain symptoms of Painful bladder syndrome following sacral neuromodulation.

Efficacy of sacral neuromodulation on urological diseases: a multicentric research project

INTRODUCTION AND AIM OF THE STUDY

Sacral neuromodulation has been used as a safe, effective treatment option for patients with lower urinary tract dysfunction (LUTD). Several clinical studies demonstrated its positive effects on refractory urge incontinence, non-osbstructive urinary retention, urgency frequency syndrome, as well as on other non- urological disorders, such as fecal incontinence and chronic constipation. The aim of this research project was to evaluate the efficacy and safety of sacral neuromodulation on the management of LUTD refractory to the standardized first line treatment options.

MATERIALS AND METHODS

We retrospectively collected and evaluated data from patients undergoing sacral neuromodulations between September 2001 and November 2010 in 4 Urological Centres of North-East Italy. The patients were affected by Overactive Bladder Syndrome (OAB), Urinary Retention (UR), Fecal Incontinence (FI), Constipation (CO), Chronic Pelvic Pain (CPP). All the patients were evaluated with voiding diaries, before and after implantation.Patients included in the present evaluation were followed up in a network of 4 Italian urological centres, which participate to in the Italian Clinical Service project - a national urological database and medical care project aiming at describing and improving the use of implantable urological devices in the Italian clinical practice. Continuous normally distributed variables were reported as the mean value ± standard deviation (SD). Continuous non-normally distributed variables were presented as the median values and an interquartile range (IQR). The t-test and Wilcoxon test were used to compare continuous variables, as appropriate. A two-sided p <0.05 was considered statistically significant.

RESULTS

Overall, 157 patients underwent implantation of sacral neuromodulator during the period under review. Eighty-three out of 157 (53%) patients complained of OAB; 52 (33%) of UR; 5 (3%) of faecal incontinence; 4 (2%) of chronic constipation; 12 (8%) of CPP. The median follow- up was 11 months (IQR 1 - 91 months). In patients treated for OAB, we documented a statistically significant reduction in the mean number of: incontinence episodes/die, pads/die, daily micturitions, nocturnal micturitions and global micturitions. In patients treated for UR, we observed a statistically significant reduction in the mean post- voiding residual volume and in the number of self catheterization. Interpretation of results: It is difficult to translate into quantifiable data the subjective perception of improvement of the symptoms expressed by the patients, as they are frequently subjective perceptions, not always numeric data. This subjective perception makes it difficult to the clinician to evaluate the real outcomes of this procedure, and makes it difficult to achieve a complete follow-up.

CONCLUSIONS

This multicenter research project confirmed the midterm safety and effectiveness of sacral neuromodulation in the treatment of refractory overactive bladder syndrome and urinary retention, showing high cure rates and low complication rates.

[Botulinum toxin versus sacral neuromodulation for idiopathic detrusor overactivity]

Idiopathic detrusor overactivity (motory urge) negatively affects the live of patients. Conservative treatment is not always effective and has multiple side effects. Sacral neuromodulation is a second line therapy for the treatment of idiopatic detrusor overactivity. Over the last decade, botulinum toxin injections have been increasingly used as alternative although there are only few randomized studies. Goal of this review is to compare efficiacy, safety and cost effectiveness of both methods.

Sacral neuromodulation and refractory overactive bladder: an emerging tool for an old problem

Overactive bladder (OAB) syndrome negatively affects the daily life of many people. Conservative treatments, such as antimuscarinics, do not always lead to sufficient improvement of the complaints and are often associated with considerable side effects resulting in treatment failure. In the case of failure or intolerable side effects, sacral neuromodulation (SNM) and botulinum toxin intravesical injections are minimally invasive and reversible alternatives. Currently, both SNM and botulinum toxin injection have FDA approval for use in OAB patients. This mini-review attempts to provide an update on SNM as a second-line management of adults with refractory OAB, based on the available clinical evidence concerning the efficacy and safety.

[Sacral neuromodulation for neurogenic bladder dysfunction]

Sacral neuromodulation (SNM) represents a promising option for managing treatment-refractory neurogenic bladder dysfunction. It remains to be seen, however, which types of neurogenic bladder dysfunction and which underlying neurological disorders best respond to SNM. Constant improvements in SNM have been achieved and it is now a minimally invasive approach performed under local anesthesia which should be considered before undertaking larger reconstructive procedures. An electrode is implanted in the S3 or S4 sacral foramen and during a test phase lasting for days to weeks the patient keeps a bladder diary to determine whether SNM has provided a relevant benefit. If the results of the test phase are positive, a neuromodulator is implanted in the gluteal area (or more rarely in the abdominal wall).The mechanism of action of SNM has not been completely clarified, but the afferent nerves most likely play a key role. It appears that SNM produces a modulation of medullary reflexes and brain centers by peripheral afferents. The implanted neuromodulation system does not lead to limitation of the patient's activities. However, it should be noted that high-frequency diathermy and unipolar electrocauterization are contraindicated in patients with neuromodulators, that during extracorporeal shock wave lithotripsy the focal point should not be in the direct vicinity of the neuromodulator or the electrode, that ultrasound and radiotherapy in the region of the implanted components should be avoided, that the neuromodulation should be discontinued in pregnancy, and that MRI examinations should only be conducted when urgently indicated and the neuromodulator is turned off.

Motor cortex stimulation in refractory pelvic and perineal pain: report of two successful cases

AIMS

In some patients, with refractory chronic pelvic and perineal pain, pain and quality of life are barely alleviated despite optimal medical treatment, infiltrations and surgical release of the pudendal nerve. The management of these patients is complex, especially after failure of neuromodulation techniques (spinal cord stimulation. S3 nerve root stimulation and direct stimulation of the pudendal nerve). We report the first two cases illustrating the value of motor cortex stimulation (MCS), in this new indication.

METHODS

The history, decision-making process, intraoperative findings and results of this technique are presented. The perineal cortical area was identified by intraoperative motor evoked potentials in the external anal sphincter, confirming its location in the primary motor cortex between the inferior and superior limb positions. As predictive value of repetitive transcranial magnetic stimulation (rTMS) in the identification of responders to MCS for pain is now established, we performed pre-operative rTMS sessions for both patients.

RESULTS

The first patient was a 74-years-old woman who reported an 11-year history of left lateral perineal pain. The second patient was a 45-year-old woman who reported a 4-year history of perineal pain following hysterectomy with ovariectomy. After respectively 40 months and 19 months of follow up, both patients reported an improvement of pain ranging from 40 to 50%. Time to onset of pain on sitting was markedly improved from a few minutes to 90 minutes, and largely contributing to improvement of activities of daily living and of quality of life.

CONCLUSION

These two first cases suggest that motor cortex stimulation constitutes a new treatment for refractory pelvic and perineal pain, and should be considered after failure of conventional neuromodulation techniques, especially spinal cord stimulation.

Transcutaneous electrical nerve stimulation: an effective treatment for refractory non-neurogenic overactive bladder syndrome?

PURPOSE

To assess the effect of transcutaneous electrical nerve stimulation (TENS) for treating refractory overactive bladder syndrome (OAB).

PATIENTS AND METHODS

A consecutive series of 42 patients treated with TENS for refractory OAB was prospectively investigated at an academic tertiary referral centre. Effects were evaluated using bladder diary for at least 48 h and satisfaction assessment at baseline, after 12 weeks of TENS treatment, and at the last known follow-up. Adverse events related to TENS were also assessed.

RESULTS

Mean age of the 42 patients (25 women, 17 men) was 48 years (range, 18-76). TENS was successful following 12 weeks of treatment in 21 (50 %) patients, and the positive effect was sustained during a mean follow-up of 21 months (range, 6-83 months) in 18 patients. Following 12 weeks of TENS treatment, mean number of voids per 24 h decreased significantly from 15 to 11 (p < 0.001) and mean voided volume increased significantly from 160 to 230 mL (p < 0.001). In addition, TENS completely restored continence in 7 (39 %) of the 18 incontinent patients. Before TENS, all 42 patients were dissatisfied or very dissatisfied; following 12 weeks of TENS treatment, 21 (50 %) patients felt satisfied or very satisfied (p < 0.001). No adverse events related to TENS were noted.

CONCLUSIONS

TENS seems to be an effective and safe treatment for refractory OAB warranting randomized, placebo-controlled trials.

Pelvic pain in urogynecology. Part II: treatment options in patients with lower urinary tract symptoms

Therapeutic options for chronic pelvic pain in women offer only a limited symptom relief. Especially in the patient with lower urinary tract symptoms (LUTS), where overlap of pain, storage and voiding symptoms is common, data on the efficacy of treatment of pain are limited. We conducted a literature review to detect articles which pertained to female patients with LUTS and pelvic pain and we included articles which evaluated the efficacy of the treatment of pelvic pain. Forty-one articles were detected, which included nerve stimulation (sacral and pudendal), intravesical instillations and injections, oral pharmacological treatments, periurethral injections as well as physical and manual therapy as treatment options. Only five controlled trials were found, which did not show superiority of the active treatment versus placebo. Although some treatment options show promising results in the treatment of pelvic pain in patients with LUTS, more randomised controlled trials are needed to confirm these results.

Inhibition of bladder overactivity by stimulation of feline pudendal nerve using transdermal amplitude-modulated signal (TAMS)

OBJECTIVE

• To develop a non-invasive neuromodulation method targeting the pudendal nerve.

MATERIALS AND METHODS

• Bladder overactivity induced by acetic acid (AA) irritation was partially suppressed by electrical stimulation of the pudendal nerve in α-chloralose anaesthetized cats using a transdermal amplitude-modulated signal (TAMS).

RESULTS

• During cystometrography (CMG), intravesical infusion of 0.25% AA significantly decreased the mean (se) bladder capacity to 28.8 (5.9)% of the capacity measured during saline infusion. • The TAMS stimulation inhibited AA-induced bladder overactivity at 5, 7 and 10 Hz, and significantly increased the mean (se) bladder capacity to 61.8 (9.9)%, 51.3 (14.5)%, 53.6 (14.9)%, respectively, of the control capacity during saline infusion, whereas stimulation at 20-40 Hz had no effect. • Under isovolumetric conditions at a bladder volume ranging between 130 to 160% of the bladder capacity measured during AA infusion, TAMS stimulation at all frequencies (5-40 Hz) significantly suppressed the irritation-induced rhythmic bladder contractions, reduced the area under the bladder pressure curve, and decreased the frequency of bladder contractions. However, the amplitude of rhythmic bladder contractions was only significantly decreased at stimulation frequencies of 5-20 Hz. • At bladder volumes above the AA control capacity, TAMS stimulation with frequencies of 20-30 Hz had an excitatory effect, resulting in large amplitude (>25 cmH(2) O) bladder contractions.

CONCLUSIONS

• TAMS stimulation targeting the cat pudendal nerve can inhibit C-fibre afferent-mediated bladder overactivity. • Thus, clinical research seems warranted to explore the usefulness of this technology for patients with overactive bladder symptoms.

Sacral neuromodulation for treating neurogenic bladder dysfunction: clinical and urodynamic study

PURPOSE

The efficacy of sacral neuromodulation for treating refractory idiopathic lower urinary tract dysfunction is now well established. Nevertheless, results of this technique in neurological patients are still controversial. The aim of this retrospective study was to assess the results of sacral neuromodulation in neurogenic bladder dysfunction.

MATERIALS AND METHODS

Between 1998 and 2008, a percutaneous nerve evaluation or a two-stage technique was performed in 62 patients (mean age 50.5 ± 14.8 years) with neurogenic lower urinary tract dysfunction. Before and during the temporary stimulation, each patient had a urodynamic evaluation and performed a bladder diary. The test was considered positive if the clinical and urodynamic improvement was over 50% and if the symptoms reappeared after turning the stimulation off.

RESULTS

Lower urinary tract dysfunction was detrusor overactivity in 34 cases and chronic urinary retention in 28 cases. A detrusor-sphincter dyssynergia (DSD) was associated in nine cases. Out of the 62 patients, 41 patients (66.1%) had more than 50% improvement on urodynamic evaluation and bladder diary and 37 were implanted. With a mean follow-up of 4.3 ± 3.7 years, results remained similar to the evaluation phase in 28 cases (75.7%), were partially altered in three cases (8.1%) and lost in six cases (16.2%). In these six cases, neuromodulation failed on average 12.0 ± 12.4 months after implantation.

CONCLUSION

Sacral neuromodulation seems to constitute a serious therapeutic option for patients with neurogenic lower urinary tract dysfunction. However, its results depend on the type of the underlying neurologic disease and in particular, whether it may progress or not.

[Therapy-refractory overactive bladder: alternative treatment approaches]

The treatment of patients with overactive bladder (OAB) refractory to conventional treatment is gaining clinical significance. This article intends to review alternative therapy options for patients with OAB refractory to conventional treatment. A search of the PubMed database as well as the abstracts presented at the European Association of Urology and the American Urological Association annual meetings was conducted. Keywords used during this search included overactive bladder (OAB) refractory to conventional treatment, electromotive drug administration (EMDA), sacral neuromodulation, augmentation cystoplasty and cystectomy. Eighteen articles with an adequate number of patients were identified. All articles published before 2001 were not included in this analysis. Because of first-line treatment failure, 30% of the patients required alternative treatment. This included EMDA, botulinum toxin injections into the detrusor, sacral neuromodulation, augmentation cystoplasty or cystectomy. Based on this review it appears that a significant improvement in micturition parameters, continence and in quality of life was achieved. Overall EMDA, intradetrusor injections of botulinum toxin and sacral neuromodulation seem to be highly effective and safe. Augmentation cystoplasty or cystectomy remains the last choice of treatment in refractory cases.Overall EMDA, intradetrusor injections of botulinum toxin and sacral neuromodulation seem to be highly effective and safe. Augmentation cystoplasty or cystectomy remains to be the last choice of treatment in refractory cases.

Pelvic electrical neuromodulation for the treatment of overactive bladder symptoms

Overactive bladder syndrome negatively affects the daily life of many people. First-line conservative treatments, such as antimuscarinics, do not always lead to sufficient improvement of the complaints and/or are often associated with disabling adverse effects leading to treatment failure. Electrical stimulation of the sacral nerves has emerged as an alternative and attractive treatment for refractory cases of bladder overactivity. Few theories attempted to explain its mechanism of action which remains elusive. It involves percutaneous posterior tibial nerve stimulation and more commonly sacral neuromodulation. For the latter, temporary sacral nerve stimulation is the first step. If the test stimulation is successful, a permanent device is implanted. The procedure is safe and reversible. It carries a durable success rate. The technique should be combined with careful followup and attentive adjustments of the stimulation parameters in order to optimize the clinical outcomes. This paper provides a review on the indications, possible mechanisms of action, surgical aspects and possible complications, and safety issues of this technique. The efficacy of the technique is also addressed.