Sacral Neuromodulation: Device Improvement and Current Applications in Urology.

Sacral neuromodulation (SNM) offers a therapeutic approach to urological patients suffering from idiopathic overactive bladder (OAB) syndrome, with or without incontinence and non-obstructive urinary retention (NOR), who are not responding to or are not compliant with conservative or medical therapies. The exact mechanism of action of SNM is not fully understood but modulation of the spinal cord reflexes and brain networks by peripheral afferents is regarded as the main pathway. Over the years, surgical techniques improved, leading to the development of the modern two-stage implantation technique. The quadripolar lead is positioned percutaneously under fluoroscopy guidance through the third sacral foramen following the trajectory of S3. The procedure can be performed under local or general anesthesia with the patient in prone position. Current applications of sacral neuromodulation in urology are increasing thanks to the recent improvements of the devices that make this a valuable option not only in conditions such as overactive bladder and non-obstructing urinary retention but also neurogenic lower urinary tract dysfunction.

Sacral neuromodulation for constipation and fecal incontinence in children and adolescents - study protocol of a prospective, randomized trial on the application of invasive vs. non-invasive technique.

BACKGROUND: A therapeutic effect of sacral neuromodulation (SNM) on fecal incontinence (FI) and quality of life has been proven in adults. SNM is, however, rarely used in pediatric cases. The aim of the study is to investigate effects of SNM in pediatric constipation in a prospective parallel-group trial. METHODS: A monocentric, randomized, unblinded, parallel-group trial is conducted. SNM is conducted in the invasive variant and in an innovative, external approach with adhesive electrodes (enteral neuromodulation, ENM). We include patients with constipation according to the ROME IV criteria and refractory to conventional options. Patients with functional constipation and Hirschsprung's disease are able to participate. Participants are allocated in a 1:1 ratio to either SNM or ENM group. Clinical data and quality of life is evaluated in regular check-ups. Neuromodulation is applied continuously for 3 months (end point of the study) with follow-up-points at 6 and 12 months. Findings are analyzed statistically considering a 5% significance level (p ≤ 0.05). Outcome variables are defined as change in (1) episodes of abdominal pain, (2) episodes of FI, (3) defecation frequency, (4) stool consistency. Improvement of proprioception, influence on urinary incontinence, quality of life and safety of treatment are assessed as secondary outcome variables. We expect a relevant improvement in both study groups. DISCUSSION: This is the first trial, evaluating effects of neuromodulation for constipation in children and adolescents and comparing effects of the invasive and non-invasive application (SNM vs. ENM). TRIAL REGISTRATION: The study is registered with clinicaltrials.gov, Identifier NCT04713085 (date of registration 01/14/2021).

[Prolonged spinal and sacral neurostimulation in children with pelvic organ dysfunction: preliminary analysis]. / Dlitel'naya spinal'naya i sakral'naya neirostimulyatsiya u detei pri narusheniyakh funktsii tazovykh organov: predvaritel'nyi analiz.

OBJECTIVE: To evaluate the clinical efficacy of long-term spinal and sacral programmable neurostimulation for pelvic organ dysfunction in patients with myelodysplasia and chronic dysfunction of the bladder and rectum. MATERIAL AND METHODS: A retrospective study included 32 children aged 1-17 years (mean 10.7) with myelodysplasia, pelvic organ dysfunction and ineffective therapy including botulinum therapy and exclusion of tethered spinal cord syndrome. All children underwent comprehensive urodynamic examination with analysis of bladder and residual urine volume, mean flow rate, intravesical pressure and total urine volume, as well as electromyographic examination. Examination was carried out before surgery, after 6, 12 and 36 months. We applied urinary diary, NBSS questionnaire and urodynamic examination data. All patients underwent neurological examinations (neurological status, magnetic resonance imaging of the spinal cord, computed tomography and radiography of the spine, electroneuromyography). The study was conducted at the neurosurgical department of the Republican Children's Clinical Hospital in Ufa between 2014 and 2022. There were 32 implantations of epidural neurostimulators for pelvic organ dysfunctions. RESULTS: Patients used epidural spinal and sacral stimulation up to 6 times a day for 10-15 min turning on the pulse generator. This method significantly increased urinary volume, decreased episodes of urinary leakage and fecal incontinence, residual volume after urination and number of periodic catheterizations compared to baseline data. Sixteen patients were very satisfied, 10 ones were moderately satisfied, and 2 patients were not satisfied with therapy. The number of bladder catheterizations per day decreased by 51.1%. Urine volume significantly increased from 131.5±16.1 to 236±16.7 ml, intravesical pressure decreased from 23.5±4.2 to 18.5±2.1 cm H2O (by 20.3%). CONCLUSION: Chronic epidural spinal and sacral stimulation can improve the quality of life in patients with pelvic organ dysfunction. This technique may be effective for pelvic organ dysfunction caused by myelodysplasia.

Does choice of anesthesia during stage 1 sacral neuromodulation testing influence outcomes?

INTRODUCTION: Staged sacral neuromodulation (SNM) testing has been shown to have a high rate of progression to permanent implantation for the management of voiding dysfunction. Stage 1 lead placement (SNM-I) can be performed under monitored anesthesia care (MAC) or general anesthesia (GA). MAC allows for interpretation of sensory and motor responses to optimize lead placement while GA only permits for motor assessment. However, patient discomfort and movement can make lead placement challenging during MAC. Herein we evaluate whether the anesthesia type impacts the progression rate to permanent implantation (SNM-II). MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent SNM-I in the operating room for wet overactive bladder between 2005 and 2023. Patients were divided into two groups based on the type of anesthesia used, MAC or GA. Clinical variables and progression to SNM-II were compared between cohorts. Progression to SNM-II was based on ≥50% symptomatic improvement during a 1-2 week trial period following SNM-I. RESULTS: Of 121 patients included in the study, 95 (79%) underwent MAC and 26 (21%) GA for SNM-I. No difference in the progression rate to SNM-II was noted between groups (MAC, 68/95 patients, 72%; GA, 19/26, 73%; p = 0.39). We also found no difference when comparing the GA group to the 26 most recent MAC patients (MAC, 20/26 patients, 77%; GA, 19/26, 73%; p = 0.48). CONCLUSION: Types of anesthesia for SNM-I did not affect rate of progression to SNM-II. The result lends support to the reliance on motor responses alone for lead placement during SNM-I.

Effectiveness, safety and cost-effectiveness of sacral neuromodulation for idiopathic slow-transit constipation: a systematic review.

AIM: Sacral neuromodulation (SNM) is a minimally invasive treatment option for functional constipation. Evidence regarding its effectiveness is contradictory, driven by heterogeneous study populations and designs. The aim of this study was to assess the effectiveness, safety and cost-effectiveness of SNM in children and adults with refractory idiopathic slow-transit constipation (STC). METHOD: OVID Medline, OVID Embase, Cochrane Library, the KSR Evidence Database, the NHS Economic Evaluation Database and the International HTA Database were searched up to 25 May 2023. For effectiveness outcomes, randomized controlled trials (RCTs) were selected. For safety outcomes, all study designs were selected. For cost-effectiveness outcomes, trial- and model-based economic evaluations were selected for review. Study selection, risk of bias and quality assessment, and data extraction were independently performed by two reviewers. For the intervention 'sacral neuromodulation' effectiveness outcomes included defaecation frequency and constipation severity. Safety and cost-effectiveness outcomes were, respectively, adverse events and incremental cost-effectiveness ratios. RESULTS: Of 1390 records reviewed, 67 studies were selected for full-text screening. For effectiveness, one cross-over and one parallel-group RCT was included, showing contradictory results. Eleven studies on safety were included (four RCTs, three prospective cohort studies and four retrospective cohort studies). Overall infection rates varied between 0% and 22%, whereas reoperation rates varied between 0% and 29%. One trial-based economic evaluation was included, which concluded that SNM was not cost-effective compared with personalized conservative treatment at a time horizon of 6 months. The review findings are limited by the small number of available studies and the heterogeneity in terms of study populations, definitions of refractory idiopathic STC and study designs. CONCLUSION: Evidence for the (cost-)effectiveness of SNM in children and adults with refractory idiopathic STC is inconclusive. Reoperation rates of up to 29% were reported.

Seminal papers in urology: two-year outcomes of Sacral Neuromodulation Versus OnabotulinumtoxinA for refractory urgency urinary incontinence: a Randomized Trial.

In this critical review, we explore the study design, strengths and limitations of the paper: "Two-Year Outcomes of Sacral Neuromodulation Versus OnabotulinumtoxinA for Refractory Urgency Urinary Incontinence: A Randomized Trial." The paper reports 24 month follow-up data of the landmark ROSETTA trial. This multi-centre, open-labelled parallel randomised trial allocated females 1:1 to receive Sacral Neuromodulation (SNM) or OnabotulinumtoxinA(BTX) 200 units (U). The primary outcome was change in mean daily urinary urgency incontinence episodes (UUIE) over 24 months. The study did not demonstrate a difference between treatments (-3.88 vs. -3.50 episodes per day), however women treated with BTX were more satisfied; but reported higher rates of UTI. The two treatments provide comparable third-line treatment options for patients with refractory urgency urinary incontinence.

Long-Term Cost Analysis of Third-Line Treatment Options for Overactive Bladder.

INTRODUCTION: We aimed to analyze the long-term cost of overactive bladder third-line treatments. METHODS: This insurance claims review analyzed the 2015 to 2020 MarketScan (MKS) claims data set subjects age ≥ 18, diagnosis of overactive bladder (OAB) using ICD-9/ICD-10 codes and receipt of treatment for percutaneous tibial nerve stimulation, sacral neuromodulation (SNM), or botulinum A. Age, gender, treatment types, and cost were extracted. Treatment costs were aggregated at the level of patient and treatment type for total payment and patient contribution by combining copay, coinsurance, and deductible. We used the Wilcoxon rank-sum test for continuous and chi-square test for categorical variables. SAS v9.4 was used for analyses. Significance was set at P < .05. RESULTS: We identified 17,755 patients from the commercial claims MKS and 10,912 patients from the Medicare supplemental (MDC) database with mean age 50.7±11.1 and 75.5±7.6 years, respectively, who underwent ≥ 1 third-line OAB treatment. Patients receiving third-line treatment were predominantly female (84.9%, MKS, 74.8%, MDC). Long-term costs over a 15-year period were estimated. Percutaneous tibial nerve stimulation is the most expensive in terms of total net payment ($105,337.50 MKS, $94,102.50 MDC) and patient contribution ($9177.60 MKS, $3921.00 MDC). Total net payment for botulinum A was $67,968 (MSK), $54,261 (MDC), and patient contribution cost was $2850 (MSK), $1110 (MDC). The most cost-effective option was SNM in terms of both total net payment ($5179.10 MKS, $6099.00 MDC) and patient contribution ($59.10 MKS, $60.00 MDC). CONCLUSIONS: SNM was the most cost-effective third-line treatment for OAB looking over a 15-year period in terms of both total net payment and patient contribution.

Sensing in Sacral Neuromodulation: A Feasibility Study in Subjects With Urinary Incontinence and Retention.

OBJECTIVES: Sacral neuromodulation (SNM) therapy standard of care relies on visual-motor responses and patient-reported sensory responses in deciding optimized lead placement and programming. Automatic detection of stimulation responses could offer a simple, consistent indicator for optimizing SNM. The purpose of this study was to measure and characterize sacral evoked responses (SERs) resulting from sacral nerve stimulation using a commercial, tined SNM lead. MATERIALS AND METHODS: A custom external research system with stimulation and sensing hardware was connected to the percutaneous extension of an implanted lead during a staged (tined lead) evaluation for SNM. The system collected SER recordings across a range of prespecified stimulation settings (electrode configuration combinations for bipolar stimulation and bipolar sensing) during intraoperative and postoperative sessions in 21 subjects with overactive bladder (OAB) and nonobstructive urinary retention (NOUR). Motor and sensory thresholds were collected during the same sessions. RESULTS: SERs were detected in all 21 subjects. SER morphology (number of peaks, magnitude, and timing) varied across electrode configurations within and across subjects. Among subjects and electrode configurations tested, recordings contained SERs at motor threshold and/or sensory threshold in 75% to 80% of subjects. CONCLUSIONS: This study confirmed that implanted SNM leads can be used to directly record SERs elicited by stimulation in subjects with OAB and NOUR. SERs were readily detectable at typical SNM stimulation settings and procedural time points. Using these SERs as possible objective measures of SNM response has the capability to automate patient-specific SNM therapy, potentially providing consistent lead placement, programming, and/or closed-loop therapy.

Do patients experience decisional regret after sacral neuromodulation for refractory overactive bladder?

OBJECTIVE: Success following urological procedures is traditionally defined through objective endpoints. This approach may not capture the impact on patient satisfaction. There is a paucity of literature evaluating patient-centered metrics such as satisfaction and decisional regret in the field of urology. This study investigates long-term satisfaction and decisional regret amongst patients who underwent sacral neuromodulation (SNM) for the treatment of refractory overactive bladder (OAB). MATERIALS AND METHODS: This study retrospectively reviewed patients who underwent SNM for refractory OAB from 2015 to 2022 at a single institution serving an ethnically diverse and underrepresented community. Demographic data were collected through chart review and surveys conducted via telephone calls. Patient satisfaction and decisional regret was measured with the validated modified SDS-DRS scale (satisfaction with decision scale-decision regret scale). Descriptive statistics, Wilcoxan rank sum, and median regression analyses were performed using STATA 15.0 with p < 0.05 as significant. RESULTS: Out of 191 patients who underwent SNM, 63 were unreachable (wrong number in chart, number not in service, patient did not answer, deceased). Eighty-nine out of 128 patients reached agreed to participate (70% response rate). The mean time since surgery was 37.3 ±25.2 months. The median satisfaction with decision score was 4.0 (IQR: 3.7-4.7) with a score of 1 correlating with low satisfaction and a score of 5 correlating with high satisfaction. The median decisional regret score was 2.0 (IQR: 1.2-2.9) with a score of 1 correlating with low decisional regret and a score of 5 correlating with strong decisional regret. Ten patients reported complications after surgery, which was significantly associated with lower SDS and higher DRS scores (p < 0.01), and persisted after adjusting for age, body mass index, sex, and comorbidities (SDS ß coef: -0.84, 95% CI: -1.5 to 0.15, p = 0.02; DRS ß coef: 1.48, 95% CI: 0.55-2.41, p < 0.01). CONCLUSIONS: Patients who underwent SNM for refractory OAB overall had low regret and high satisfaction with their decision at an average 3 years of follow-up. As expected, those who developed postoperative complications had worse scores. The inclusion of patient-centric outcomes is imperative when determining the success of a surgical procedure and is useful for shared decision-making when advancing to third-line therapy for OAB. Longer-term follow-up is necessary to assess durability of high satisfaction and low regret over time.

Sacral neuromodulation therapy for urinary and defecatory disorders: experience in a Latin American public hospital

Abstract Objective: To show the experience of a Latin American public hospital, with SNM in the management of either OAB, NOUR or FI, reporting feasibility, short to medium-term success rates, and complications. Methods: A retrospective cohort was conducted using data collected prospectively from patients with urogynecological conditions and referred from colorectal surgery and urology services between 2015 and 2022. Results: Advanced or basic trial phases were performed on 35 patients, 33 (94%) of which were successful and opted to move on Implantable Pulse Generator (GG) implantation. The average follow-up time after definitive implantation was 82 months (SD 59). Of the 33 patients undergoing, 27 (81%)reported an improvement of 50% or more in their symptoms at last follow-up. Moreover, 30 patients (90%) with a definitive implant reported subjective improvement, with an average PGI-I "much better" and 9 of them reporting to be "excellent" on PGI-I. Conclusion: SNM is a feasible and effective treatment for pelvic floor dysfunction. Its implementation requires highly trained groups and innovative leadership. At a nation-wide level, greater diffusion of this therapy among professionals is needed to achieve timely referral of patients who require it.

Evaluation of the efficacy of sacral neuromodulation in the treatment of voiding dysfunction after endometriosis surgery.

Pelvic surgery for endometriosis is associated with a risk of bladder and digestive sequelae. Sacral neuromodulation (SNM) has been shown to be effective in the treatment of overactive bladder (OAB) and voiding dysfunction (VD). This study aimed to evaluate the efficacy of sacral neuromodulation (SNM) in treating voiding dysfunction (VD) following endometriosis surgery. A retrospective analysis was conducted on data from women who underwent SNM testing for persistent VD after endometriosis surgery. The study included 21 patients from a French tertiary referral center. Patient characteristics, lower urinary tract symptoms, urodynamic findings, SNM procedures, and outcomes were assessed. The primary outcome was the success of SNM treatment for VD. After a median follow-up of 55 months, 60% of patients achieved successful outcomes, with significant improvements of VD and quality of life. Moreover, more than half of patients who required clean intermittent self-catheterization (CISC) before SNM were able to wean off CISC. Complications such as infections and paraesthesia were observed, but overall, SNM was found to be effective and well tolerated. Age and the interval between endometriosis surgery and SNM testing were associated with treatment success. This study adds to the limited existing literature on SNM for VD after endometriosis surgery and suggests that SNM can be a valuable therapeutic option for these patients. Further research is needed to identify predictive factors and mechanisms underlying the effectiveness of SNM in this context. MRI-compatible and rechargeable devices, has improved the feasibility of SNM for these patients. In conclusion, SNM offers promise as a treatment option for persistent VD after endometriosis surgery, warranting further investigation. LEVEL OF EVIDENCE: 4.

Development of a predictive tool for sacral nerve modulation implantation in the treatment of non-obstructive urinary retention and/or slow urinary stream: a study from the Neuro-Urology Committee of the French Association of Urology.

PURPOSE: This study aimed to seek predictive factors and develop a predictive tool for sacral nerve modulation (SNM) implantation in patients with non-obstructive urinary retention and/or slow urinary stream (NOUR/SS). METHODS: This study was designed as a retrospective study including all patients who have undergone a two-stage SNM for NOUR/SS between 2000 and 2021 in 11 academic hospitals. The primary outcome was defined as the implantation rate. Secondary outcomes included changes in bladder emptying parameters. Univariate and multivariable logistic regression analysis were performed and determined odds ratio for IPG implantation to build a predictive tool. The performance of the multivariable model discrimination was evaluated using the c-statistics and an internal validation was performed using bootstrap resampling. RESULTS: Of the 357 patients included, 210 (58.8%) were finally implanted. After multivariable logistic regression, 4 predictive factors were found, including age (≤ 52 yo; OR = 3.31 CI95% [1.79; 6.14]), gender (female; OR = 2.62 CI95% [1.39; 4.92]), maximal urethral closure pressure (≥ 70 cmH2O; OR: 2.36 CI95% [1.17; 4.74]), and the absence of an underlying neurological disease affecting the lower motor neuron (OR = 2.25 CI95% [1.07; 4.76]). Combining these factors, we established 16 response profiles with distinct IPG implantation rates, ranging from 8.7 to 81.5%. Internal validation found a good discrimination value (c-statistic, 0.724; 95% CI 0.660-0.789) with a low optimism bias (0.013). This allowed us to develop a predictive tool ( https://predictivetool.wixsite.com/void ). CONCLUSION: The present study identified 4 predictive factors, allowing to develop a predictive tool for SNM implantation in NOUR/SS patients, that may help in guiding therapeutic decision-making. External validation of the tool is warranted.

Pathways and parameters of sacral neuromodulation in rats.

The stimulation paradigm for sacral neuromodulation has remained largely unchanged since its inception. We sought to determine, in rats, whether stimulation-induced increases in bladder capacity correlated with the proportion of sensory pudendal (PudS) neurons at each stimulated location (L6, S1). If supported, this finding could guide the choice of stimulation side (left/right) and level (S2, S3, S4) in humans. Unexpectedly, we observed that acute stimulation at clinically relevant (low) amplitudes [1-1.5 × motor threshold (Tm)], did not increase bladder capacity, regardless of stimulus location (L6 or S1). More importantly for the ability to test our hypothesis, there was little anatomic variation, and S1 infrequently contributed nerve fibers to the PudS nerve. During mapping studies we noticed that large increases in PudS nerve activation occurred at amplitudes exceeding 2Tm. Thus, additional cystometric studies were conducted, this time with stimulation of the L6-S1 trunk, to examine further the relationship between stimulation amplitude and cystometric parameters. Stimulation at 1Tm to 6Tm evoked increases in bladder capacity and decreases in voiding efficiency that mirrored those produced by PudS nerve stimulation. Many animal studies involving electrical stimulation of nerves of the lower urinary tract use stimulation amplitudes that exceed those used clinically (∼1Tm). Our results confirm that high amplitudes generate immediate changes in cystometric parameters; however, the relationship to low-amplitude chronic stimulation in humans remains unclear. Additional studies are needed to understand changes that occur with chronic stimulation, how these changes relate to therapeutic outcomes, and the contribution of specific nerve fibers to these changes.NEW & NOTEWORTHY Acute low-amplitude electrical stimulation of sacral nerve (sacral neuromodulation) did not increase bladder capacity in anesthetized CD, obese-prone, or obese-resistant rats. Increasing stimulation amplitude correlated with increases in bladder capacity and pudendal sensory nerve recruitment. It is unclear how the high-amplitude acute stimulation that is commonly used in animal experiments to generate immediate effects compares mechanistically to the chronic low-amplitude stimulation used clinically.

Sacral neuromodulation in endometriosis - A promising treatment option for chronic pelvic pain.

INTRODUCTION: Chronic pelvic pain (CPP) affects over one fifth of women worldwide, and endometriosis is one of the most common causes. In the present study, we examined whether sacral neuromodulation (SNM) is effective in the treatment of refractory chronic pelvic pain in women with endometriosis. MATERIAL AND METHODS: This multicenter prospective pilot study was started in 2017 and includes patients with chronic pelvic pain with no other obvious pathology than endometriosis. Other treatment options have been tried or they are unsuitable. Patients underwent SNM implantation. The main outcome was postoperative pain reduction and secondary outcome was quality of life. The following questionnaires were used to assess the outcomes: Brief pain inventory (BPI), clinical global impression - improvement (CGI-I), 15D-measure of health-related quality of life, and Biberoglu and Behrman (B&B) score. RESULTS: A total of 35 patients underwent the SNM procedure and, at the time of analysis, 15 patients had returned one-year questionnaires. The patients had a history of endometriosis for a median of 5.5 (interquartile range 2-9) years, with no correlation between the severity of symptoms and the duration of the disease (p = 0.158). A total of 31 patients (89%) were implanted with the internal pulse generator. There were statistically significant changes in BPI pain-related items. Worst experienced daily pain decreased among those who returned 12-month questionnaires from median 9 to 5 (p = 0.006), average daily pain from 6 to 3.5 (p = 0.004), and least daily pain from 3 to 1 (p = 0.004). Based on the CGI questionnaire (n = 14), at 12 months nine patients (60%) experienced great improvement in their symptoms, three patients (20%) much improvement and two patients (13%) minimal improvement. None of the patients experienced worsening of their symptoms. There was a statistically significant change in overall 15D score at 1 month (p < 0.001), 6 months (p = 0.001) and 12 months (p = 0.018), when the results were compared to baseline values. Median B&B score also improved significantly and decreased from a baseline value of 8 (4-12) to 4.5 (0-6), p = 0.002. CONCLUSIONS: Based on the preliminary findings of our study, SNM might be a promising treatment of CPP in endometriosis patients.

[Sacral neuromodulation for bladder voiding dysfunction: Experience at a French university center]. / Neuromodulation sacrée pour trouble de la vidange vésicale : expérience d'un centre universitaire français.

OBJECTIVE: To report the experience of a university hospital center with sacral neuromodulation for patients with bladder voiding disorders. MATERIAL AND METHODS: All patients who underwent sacral neuromodulation between 1998 and 2022 for bladder voiding disorders were included. Medical records were analyzed retrospectively, and population, efficacy and follow-up data were collected. RESULTS: A total of 134 patients underwent test implantation and 122 patients were analyzed. 68 patients (56%) were implanted with a definitive neuromodulation device. Mean age was 43±16 years and BMI 25.5±5.4kg/m2. 74% were women. Bladder voiding disorder was due to sphincter hypertonia in 51% of cases, with associated bladder hypocontractility in 29%. The spontaneous micturition rate after implantation increased from 34% to 92%. Implantation results appeared to be better in patients with sphincter hypertonia, whether or not associated with bladder hypocontractility. The benefit was most often present with a frequency of 5Hz (54.4%). Side-effects were present in 52% of cases at 5 years, and in 85% of cases were pain in relation to the implanted devices. They resolved under medical treatment or after revision of the device (27% of cases at 5 years). CONCLUSION: SNM is effective in micturition recovery, but has side effects. Urodynamic mechanism and etiology may provide clues for modulating NMS box settings and determining predictive factors for NMS success. Data from other centers are needed to identify reliable predictive factors.

Long-term cost-effectiveness analysis of sacral neuromodulation in the treatment of severe faecal incontinence.

AIM: The aim of this study was to evaluate the long-term cost-effectiveness of sacral neuromodulation in the treatment of severe faecal incontinence as compared with symptomatic management. METHODS: In the public health field, a micro-costing evaluation method was conducted from the perspectives of the health system and the society. The incremental cost-effectiveness ratio was used as a decision index, and we considered various scenarios to evaluate the impact of the cost of symptomatic management and percutaneous nerve evaluation success rate in its calculation. Clinical data were retrieved from a consecutive cohort of 93 patients with severe faecal incontinence undergoing sacral neuromodulation after a failure of conservative (pharmacological and biofeedback) and/or surgical (sphincteroplasty) first-line treatments were considered. RESULTS: The long-term incremental cost-effectiveness ratio comparing sacral neuromodulation versus symptomatic management was 14347€/QALY and 28523€/QALY from the societal and health service provider's perspectives, respectively. If the definitive pulse generator implant success rate was 100%, incremental cost-effectiveness would correspond to 6831€/QALY and 16761€/QALY, respectively. CONCLUSIONS: Sacral neuromodulation may be considered a cost-effective technique in the long-term treatment of severe faecal incontinence from the societal and health care sector perspectives. Improving patient selection and determining the predictive outcome factors for successful sacral neuromodulation in the treatment of faecal incontinence would improve cost-effectiveness.

Sacral neuromodulation for low anterior resection syndrome: current status-a systematic review and meta-analysis.

INTRODUCTION: It is estimated that approximately 70% of patients with rectal cancer who undergo surgery will suffer from Low Anterior Resection Syndrome (LARS). In the last decades, sacral neuromodulation (SNM) has been widely used in urinary dysfunction and in faecal incontinence refractory to medical treatment. Its application in LARS has been investigated and has shown promising results. The paper's aim is to present a systematic review and meta-analysis of the available literature and evaluate the therapeutic success of SNM in patients with LARS. METHODS: A systematic search was performed in international health-related databases: Cochrane Library, EMBASE, PubMed and SciELO. No restrictions on year of publication or language were applied. Retrieved articles were screened and selected according to set inclusion criteria. Data items were collected and processed for each included article and a meta-analysis was done according to the PRISMA guidelines. The primary outcome was the number of successful definitive SNM implants. Further outcomes included changes in bowel habits, incontinence scores, quality of life scores, anorectal manometry data and complications. RESULTS: A total of 18 studies were included, with 164 patients being submitted to percutaneous nerve evaluation (PNE) with 91% responding successfully. During follow-up of therapeutic SNM some devices were explanted. The final clinical success rate was 77% after permanent implant. Other outcomes, such as the frequency of incontinent episodes, faecal incontinence scores, quality of life scores were overall improved after SNM. The meta-analysis showed a decrease in 10.11 incontinent episodes/week; a decrease of 9.86 points in the Wexner score and an increase in quality of life of 1.56 (pooled estimate). Changes in anorectal manometry were inconsistent. Local infection was the most common post-operative complication, followed by pain, mechanical issues, loss of efficacy and haematoma. DISCUSSION/CONCLUSION: This is the largest systematic review and meta-analysis concerning the use of SNM in LARS patients. The findings support the available evidence that sacral neuromodulation can be effective in the treatment of LARS, with significant improvement in total incontinent episodes and patients´ quality of life.

Is sacral neuromodulation effective and safe in pregnancy? A systematic review.

OBJECTIVE: We systematically assessed all available evidence on the efficacy and safety of sacral neuromodulation (SNM) in pregnancy. METHODS: On September 2022, a thorough search was done on Ovid, PubMed, Scopus, ProQuest, Web of Science, and The Cochrane Library. We chose studies that included pregnant women who had SNM previously. Two authors independently evaluated the quality of the study using a standardized tool of JBI. Studies were given a risk of bias rating of low, moderate, or high. Given the descriptive nature of this study, we utilized descriptive statistics to report demographic and clinical features. For continuous variables, we used mean and standard deviation, and for dichotomous data, we used frequencies and percentages. RESULTS: Out of 991 abstracts screened, only 14 studies met our inclusion criteria and were included in the review. Overall, the quality of the evidence available from the literature is low based on the design of the included studies. Fifty-eight women, including 72 pregnancies, had SNM. The indication of SNM implantation was filling phase disorders in 18 cases (30.5%), voiding dysfunction in 35 women (59.3%), IC/BPS in two cases (3.5%), and fecal incontinence. In 38 pregnancies (58.5%), the SNM status was ON during pregnancy. Forty-nine cases delivered a full-term baby (75.4%), 12 cases had pre-term labor (18.5%), two miscarriages, and two postterm pregnancies happened. The most complications in patients with devices were urinary tract infection in 15 women (23.8%), urinary retention in six patients (9.5%), and pyelonephritis in two cases (3.2%). The findings revealed that when the device was deactivated, 11 cases out of the 23 patients (47.8%) had full-term pregnancies, while in ON status, 35 out of the 38 pregnant women (92.1%) had full-term pregnancies. Nine preterm labors in OFF (39.1%), and two in ON status (5.3%) were recorded. The results revealed that this difference was statistically significant (p = 0.002), and those who turned SNM of them off had more preterm labor. Although the studies reported all neonates had a healthy status, two children had chronic motor tic problems and a pilonidal sinus in a case with an active SNM in pregnancy. However, there was no association between the SNM status and pregnancy or neonatal complications (p = 0.057). CONCLUSION: SNM activation in pregnancy seems safe and effective. The choice of whether to activate or deactivate SNM should be made on an individual basis given the current SNM evidence.

Sacral neuromodulation for refractory ulcerative colitis: safety and efficacy in a prospective observational series of eight patients.

PURPOSE: Ulcerative colitis (UC) treatment is mainly based on immunosuppressive therapy. As anti-inflammatory effects of sacral neuromodulation (SNM) have been previously reported in animal models, we conducted a pilot study aimed at assessing clinical, biological, and endoscopic response but also safety of SNM use in UC refractory to medical therapy. METHODS: Adult patients with histologically proven UC resistant to immunosuppressive therapy were invited to enroll in the study. Primary outcome was the rate of UC remission (UCDAI score ≤ 2, without any criteria > 1) at 8 weeks (W8). Secondary outcomes were biological and endoscopic response also evaluated at W8 and W16. Subsequently, every patient was followed every 6 months. Adverse events were prospectively collected for safety assessment during the follow-up. RESULTS: Eight patients, with mean age 47 years old, suffering from UC for 2-13 years were included. There were no complications in relation to SNM procedure. The acceptance of the device was excellent in all patients. Clinical and endoscopic remission was obtained at W8 in one patient (12.5%) and three other patients (37.5%) were responders at W16. At review (mean follow-up of 4 years), two patients (25%) were in remission and two (25%) were responders. CONCLUSION: SNM application is safe in patients suffering from refractory UC. Effects on disease activity were mainly observed after 16 weeks. Larger prospective studies are mandatory, but SNM could be a way to reinforce medical therapy and reduce the use of immunosuppressive drugs.

Five-year Results from the Prospective, Multicenter, Observational SOUNDS Study of Patients with Overactive Bladder Treated with the InterStim System for Sacral Neuromodulation.

BACKGROUND: Although sacral neuromodulation (SNM) for overactive bladder (OAB) is an established therapy, there is a lack of high-quality, long-term data on real-life practice. OBJECTIVE: To report on real-life therapeutic effectiveness, quality of life (QoL), disease severity, and safety as well as patient-reported symptom bother after approximately 5 yr of follow-up. DESIGN, SETTING, AND PARTICIPANTS: A total of 291 OAB patients were enrolled at 25 French sites according to local standard of care. Sacral neuromOdUlation with InterStim therapy for intractable lower uriNary tract DySfunctions (SOUNDS) enrolled both de novo and replacement patients, and a total of 229 patients were permanently implanted. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Over the course of the study, patients were followed up six times with two follow-ups in the year after implantation and annually thereafter. Of the patients, 154 completed the final follow-up after a mean of 57.7 ± 3.9 mo. RESULTS AND LIMITATIONS: The mean number of daily leaks in urinary urge incontinence (UI) patients was reduced from 4.4 ± 3.3 at baseline to 1.8 ± 2.6 after 5 yr in de novo and from 5.4 ± 4.9 to 2.2 ± 3.0 in replacement patients (both p < 0.001). Likewise, the number of voids in urinary frequency patients was reduced compared with baseline (de novo: reduced from 12.6 ± 4.0 [baseline] to 9.6 ± 4.3 [5 yr]; replacements: reduced from 11.5 ± 4.3 [baseline] to 9.2 ± 3.1 [5 yr]; both p < 0.05). Complete continence rates after 5 yr were 44% (25/57) in de novo and 33% (5/15) in replacement UI patients, and 68% (39/57) and 67% (10/15) of UI patients were categorized as therapy responders by showing a >50% improvement in leaks. Disease severity (Urinary Symptom Profile domain 2), Numeric Rating Scale-based symptom bother, and disease-specific QoL (Ditrovie) improved significantly in both groups at all visits (p < 0.001). Adverse events related to device or procedure occurred in 51% (140/274) of patients, with 66% (152/229) of the events being classified as minor (Clavien-Dindo grade I and II). Surgical revisions were reported in 39% (89/229), which include permanent explants in 15% (34/229) of patients. CONCLUSIONS: SOUNDS demonstrates the sustained effectiveness and QoL improvements of SNM in OAB patients after 5 yr in real-world conditions while maintaining an acceptable safety profile consistent with literature. PATIENT SUMMARY: This study confirmed that French overactive bladder patients had a sustained symptom and bother reduction, and improvements in quality of life up to 5 yr after sacral neuromodulation device implantation.