Intraoperative Predictors of Sacral Neuromodulation Implantation and Treatment Response: Results From the ROSETTA Trial.

PURPOSE: We determined the utility of intraoperative data in predicting sacral neuromodulation outcomes in urgency urinary incontinence. MATERIALS AND METHODS: Intraoperative details of sacral neuromodulation stage 1 were recorded during the prospective, randomized, multicenter ROSETTA trial, including responsive electrodes, amplitudes, and response strengths (motor and sensory Likert scales). Stage 2 implant was performed for stage 1 success on 3-day diary with 24-month follow-up. An intraoperative amplitude response score for each electrode was calculated ranging from 0 (no response) to 99.5 (maximum response, 0.5 V). Predictors for stage 1 success and improvement at 24 months were identified by stepwise logistic regression confirmed with least absolute shrinkage and selection operator and stepwise linear regression. RESULTS: Intraoperative data from 161 women showed 139 (86%) had stage 1 success, which was not associated with number of electrodes generating an intraoperative motor and/or sensory response, average amplitude at responsive electrodes, or minimum amplitude-producing responses. However, relative to other electrodes, a best amplitude response score for bellows at electrode 3 was associated with stage 1 failure, a lower reduction in daily urgency urinary incontinence episodes during stage 1, and most strongly predicted stage 1 outcome in logistic modeling. At 24 months, those who had electrode 3 intraoperative sensory response had lower mean reduction in daily urgency urinary incontinence episodes than those who had no response. CONCLUSIONS: Specific parameters routinely assessed intraoperatively during stage 1 sacral neuromodulation for urgency urinary incontinence show limited utility in predicting both acute and long-term outcomes. However, lead position as it relates to the trajectory of the sacral nerve root appears to be important.

Effect of pulse width variations on sacral neuromodulation for overactive bladder symptoms: A prospective randomized crossover feasibility study.

INTRODUCTION/BACKGROUND: The pulse width (PW) parameter in sacral neuromodulation (SNM) is understudied, with no evidence-based guidance available on optimal PW for urinary indications. The aim of this prospective, randomized, single-blinded, 3 × 3 cross over design study was to estimate the effect of two PW settings (60 µs, 420 µs) compared to the industry standard (210 µs) on SNM efficacy, quality of life, and device parameters in patients who were stable and satisfied with their SNM treatment. METHODS/MATERIALS: Eligible patients were previously implanted and had urge incontinence or urgency-frequency with satisfaction on SNM at time of enrollment. Patients completed a 3-day voiding diary, validated questionnaires, and device interrogations with sensory threshold assessment at baseline and after a 4-week period on each of the three PW settings, to which they were randomized. Eighteen participants completed the study, as called for by power analysis. RESULTS: Eighteen patients were enrolled in the study. Mean age was 68 years and implant duration at the time of participation was 4.4 years. While PW variations did not produce significant differences in overall objective outcomes, device parameters, including sensory threshold amplitude and battery life differed significantly. Shortened PW necessitated higher amplitude while conserving battery life. Stimulus sensation location, quality, and intensity did not differ between PW. Standard PW was chosen by 11 patients after the study, 5 chose extended, and 2 chose shortened. Those who chose alternative PW achieved significant reductions in urinary frequency from enrollment -2.23 voids/day (p = 0.015). Upon sub-analysis, patients reporting "much better" or "very much better" on extended PW achieved significant reductions in urinary frequency and nocturia at 5.6 and 0.4, compared to 8.5 and 2.16 at baseline (p = 0.005, p = <0.001). Whereas those reporting "much better" or "very much better" on shortened PW achieved significant reductions in urinary frequency at 5.15 compared to 7.35 (p = 0.026). There were no adverse events or complications. CONCLUSIONS: Overall SNM effectiveness was unchanged with alternative PW; however, 39% of patients preferred alternative to standard PW and achieved significant improvements in urinary symptoms with such. Shorter PW can also provide savings in estimated battery life without sacrificing therapeutic efficacy.

Computed tomography scanning of implanted hypoglossal nerve stimulators and approach to device malfunction: case series.

OBJECTIVE: Serious device-related complications for hypoglossal nerve stimulators are rare, but surgeons should implement a prompt and systematic approach to quickly troubleshoot a non-functioning device. METHOD: Records were queried at a single academic tertiary referral centre between January 2019 and June 2021. RESULTS: The authors present four cases of non-functioning hypoglossal nerve stimulator devices: one case in which migration of the stimulation lead required a revision implantation, one in which the implantable pulse generator was found to be non-functional intra-operatively, one case of an intramuscular sensory lead tract causing pain and one case of implantable pulse generator failure that was probably triggered by implantable cardiac device discharge. In this study, computed tomography imaging was critical to the diagnosis for the first and third cases. CONCLUSION: Given the limited complication reporting available for hypoglossal nerve stimulators, these cases highlight management and unique imaging findings. The authors present an algorithm to work-up non-functioning hypoglossal nerve stimulator devices.

Ultrasound-guided percutaneous peripheral nerve stimulation for chronic refractory neuropathic pain: a unique series.

During the last two decades, with the advent of recent technology, peripheral nerve stimulation has become an appealing modality at the forefront of pain management. In this case series, we document the clinical rationale and technical considerations on three of the most challenging cases, refractory to previous interventions, that were treated by our team with an ultrasound-guided percutaneous peripheral nerve stimulator targeting the musculocutaneous, bilateral greater occipital and subcostal nerves. At the 6-month follow-up, all patients experienced greater than 50% relief of baseline pain, with a near-complete resolution of pain exacerbations. Furthermore, to our knowledge, this is the first report of an ultrasound-guided percutaneous technique of a peripheral nerve stimulator targeting the musculocutaneous and subcostal nerves.

Peripheral nerve stimulation is a new tool used in the treatment of peripheral nerve pain. In this study, we share our experience using this technology in three unusual, difficult-to-treat chronic nerve pain presentations, targeting the musculocutaneous, bilateral greater occipital and subcostal nerves. All patients were asked about how pain levels had changed since the peripheral nerve stimulation device had been implanted. In every case, patients reported a decline in their pain level from day one. After 6 months of peripheral nerve stimulator use, all patients reported a greater than 50% pain relief.

Development of an implant technique and early experience using a novel implantable pulse generator with a quadripolar electrode array at the tibial nerve for refractory overactive bladder.

OBJECTIVES: Tibial nerve stimulation is an effective treatment for overactive bladder (OAB) and has been utilized as an in-person recurring session treatment option for many years. The primary objective of this study was to evaluate the safety and efficacy of a long-term implantable device and the method of utilizing a retrograde approach to place the device (a percutaneous implantable pulse generator [pIPG] with integrated quadripolar electrodes) at the tibial nerve (Protect PNS; Uro Medical Corp.). METHODS: A novel retrograde implant technique was developed through multiple cadaveric dissections to percutaneously implant a chronic, wireless, minimally invasive pIPG device with integrated quadripolar electrodes (now licensed to Uro Medical) at the tibial nerve. A proof-of-concept pIPG device approved as part of an FDA IDE was designed to gain early experience in subjects with refractory OAB. The pIPG was implanted in the office under local anesthesia using the novel retrograde approach, and stimulation was activated using an external wireless energy source called a transmitter. Initially, a pilot study was designed to compare outcomes in subjects randomized to either percutaneous tibial nerve stimulation (PTNS) or Protect PNS. However, due to the small sample sizes available at this time, it was not possible to compare the two groups. Thus, the purpose of this manuscript is to describe the outcome of subjects who underwent implantation of the Protect PNS system. Twelve-month safety and efficacy were evaluated. RESULTS: Nine subjects were enrolled in the randomized pilot study; 5 to the pIPG group and 4 to PTNS, and all completed the 13-week primary endpoint. Subsequently, two subjects in the PTNS group chose to cross over and have the pIPG implanted after 13 weeks. Outcomes of the seven subjects who underwent implantation of the pIPG are described. No complications related to the office procedure were noted. Two of the older model pIPG devices became nonresponsive at 1 and 4 weeks and were replaced. Six minor adverse events were reported and resolved. Subjects reported improvement in urge urinary incontinence (UUI) episodes, OAB symptoms, and quality of life. Subjects impanted with a pIPG reported a 50% reduction in UUI as early as 1 week. CONCLUSIONS: Results of this pilot study suggest that retrograde percutaneous implantation of a pIPG is a safe, minimally invasive one-stage office procedure for treatment for urge incontinence related OAB symptoms, without significant complications after 12 months follow-up. Future studies will be required to compare outcomes among treatment modalities.

[Neurolaryngology]. / Neurolaryngologie.

Neurological and neurophysiological knowledge of neuromuscular diseases is combined in neurolaryngology with experience from laryngology. Laryngeal electromyography (LEMG) is the most important diagnostic and prognostic tool in neurolaryngology. It can be combined with diagnostic electrostimulation. Interest in LEMG today extends beyond the thyroarytenoid muscle to all accessible laryngeal muscles. LEMG should be performed and interpreted according to a standardized protocol. Main applications of LEMG are confirmation, topodiagnostic and prognostic assessment of vocal fold paralysis. It is possible to differentiate fresh from old recurrent laryngeal nerve lesions as well as mechanical vocal fold fixations from paralysis. Needle guidance for botulinum toxin injections in spasmodic dysphonia and for augmentation laryngoplasty can be supported by LEMG, but also by laryngeal ultrasound. The timing of therapy for temporary and permanent augmentations, thyroplasty and reinnervation surgery may be better defined with experience from neurolaryngology. The use of diagnostic neurostimulation can reveal any remaining active movement potential of a vocal fold and thus help identify candidates for future laryngeal pacemaker treatments. Other topics in neurolaryngology include spasmodic dysphonia and underlying neurological diseases such as stroke, central vocal fold paralysis, essential tremor and Parkinson's disease. Laryngoscopic, clinical and LEMG characteristics of these diseases are presented.

Pivotal Study of Leadless Tibial Nerve Stimulation with eCoin® for Urgency Urinary Incontinence: An Open-Label, Single Arm Trial.

PURPOSE: A novel leadless tibial nerve stimulator provides a primary battery-powered, coin-sized, minimally invasive option to deliver automatic low-duty cycle stimulation for overactive bladder syndrome therapy. A pivotal trial was conducted to evaluate the safety and efficacy of this investigational device, eCoin®, for treating refractory urgency urinary incontinence. MATERIALS AND METHODS: This was a prospective, open-label, single arm trial carried out at 15 U.S. medical centers involving 137 subjects with refractory urgency urinary incontinence. After implantation in the lower leg above the fascia over the tibial nerve, eCoin delivered automated stimulation sessions for the duration of the study. The primary efficacy measure was the proportion of subjects who achieved a 50% or greater reduction from baseline in urgency urinary incontinence episodes after 48 weeks of therapy. The primary safety measure was device-related adverse events at the same time point. RESULTS: Of 137 subjects enrolled, 133 were implanted with eCoin, and 132 were included in the intention-to-treat population. Of those 132 subjects, 98% were female, mean±SD age was 63.9±10.9 years, and baseline daily urgency urinary incontinence episodes were 4.3±3.1. The primary efficacy analysis showed 68% (95% CI: 60%-76%) of subjects experienced at least a 50% reduction in urgency urinary incontinence episodes at 48 weeks post-activation; 16% of implanted subjects experienced device-related events through 52 weeks post-implantation. CONCLUSIONS: eCoin demonstrated clinical benefit for treating overactive bladder syndrome with automatic delivery of an intermittent low-duty cycle and implanted with a minimally invasive, brief procedure.

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

INTRODUCTION: Sacral neuromodulation (SNM) has been used in carefully selected patients with neurogenic lower urinary tract dysfunctions (nLUTD) for over two decades. METHODS: The aim of the current work was to perform a systematic literature review and meta-analysis of studies reporting the safety and effectiveness of SNM in patients with nLUTD (neurogenic detrusor overactivity, non-obstructive urinary retention, or a combination of both). For this purpose a systematic literature research was conducted using Embase (OvidSP), MEDLINE (OvidSP), MEDLINE In-Process Citations & Daily Update (OvidSP), MEDLINE (OvidSP) e-Pub ahead of print, Cochrane Central Register of Controlled Trials (CENTRAL), NIH Clinicaltrials.gov, and WHO International Clinical Trials Registry Platform (ICTRP) between 1998 and March 2020, supplemented by a hand search. RESULTS: Forty-seven studies were included in the systematic literature review. Twenty-one studies comprising a total of 887 patients were included in the meta-analysis of test SNM. The pooled success rate of SNM test stimulation was 66.2% (95% CI 56.9-74.4). Depending on neurogenic conditions test success rates varied greatly. Twenty-four studies with a total of 428 patients were included in the meta-analysis of permanent SNM. The success rate of pooled permanent SNM was 84.2% (95% CI 77.8-89.0). Among the identified studies, the most common adverse events (AEs) were loss of effectiveness, infection, pain at implant site, and lead migration with AE rates of 4.7%, 3.6%, 3.2%, and 3.2%, respectively. Limitations entail lower level of evidence (Oxford classification 3-4) of included studies, significant risk of bias, small sample sizes in some studies, the inclusion of retrospective case series, substantial between-study heterogeneity, heterogeneous patient populations, insufficient disease classification, and variations in terms of outcome parameters as well as techniques. Furthermore, long-term data are limited. CONCLUSION: This meta-analysis supports not only the benefits of permanent SNM for various nLUTDs but also high overall success rates, similar to idiopathic patients. Current data of the analyzed studies showed that SNM is safe for these patients. However, more vigorous studies and/or registries are needed before definitive conclusions can be drawn.

The role of pulse width manipulation compared to program changes alone for unsatisfactory sacral neuromodulation therapy: A retrospective matched-cohort analysis.

AIM: Pulse width (PW) influences neuromodulation by its impact on nerve fiber recruitment. A paucity of data regarding the manipulation of PW in sacral neuromodulation (SNM) exists. This study describes the clinical features and outcomes of PW manipulation for unsatisfactory SNM therapy. METHODS: A retrospective, single-institution review was performed of reprogrammed SNM patients between 2010 and 2019. Two cohorts were created: those with PW changes ± program changes and age-matched controls with program changes alone. Patients lacking follow-up and non-InterStim II models were excluded. RESULTS: Out of 710 SNM interrogations, 147 (20.7%) had PW changes and 80 met inclusion criteria. Most PW changes were shortened (61/80, 76.3%). Clinical features did not differ between cohorts except by indication for reprogramming. The most common indication for PW change was painful stimulation (34/80, 43%), whereas in controls it was suboptimal efficacy (76/80, 95%). Clinical success was stratified by indication. There was a higher improvement in efficacy in the PW cohort (61%, 17/28 vs. 36%, 27/76, p = .02). PW manipulation successfully relieved painful stimulation in 50% (17/34 vs. 0/3, p = .23), which was more likely with a shortened compared to extended PW (14/15, 93.3% vs. 0/6, 0%, p < .01). PW resulted in improvement in localization of the stimulus in 94% (17/18 vs. 0/1, p = .10). The subsequent lead revision or explant was significantly higher in the PW cohort (43% vs. 25%, p = .03). CONCLUSION: PW manipulation may aid the salvage of unsatisfactory SNM therapy. These findings represent an initial assessment of the role of PW in SNM, particularly regarding the efficacy and painful stimuli. The further prospective investigation is warranted.

A Supervised 3 Weeks Test Phase in Sacral Neuromodulation with a 1-Year Followup.

PURPOSE: We sought to determine whether prolonged interventional test phase increases cumulative success rate and compared success rates between early responders (ie within 1 week) and those in need for reprogramming (due to lack of efficacy) of sacral neuromodulation after 1-year followup. MATERIALS AND METHODS: In a single tertiary center prospective study (August 2015 to November 2018) 90 patients refractory to first line treatment were eligible for sacral neuromodulation, including 48 overactive bladder wet (53%), 8 overactive bladder dry (9%) and 34 nonobstructive urinary retention (38%). Patients were evaluated at weekly intervals during test phase and those not successful were reprogrammed. This could be repeated after the second week. Primary outcome was success rate after 3-week test phase and after 1-year followup. Statistical analysis was done by nonparametric tests for numeric (Mann-Whitney U) and categorical (chi2) data. RESULTS: After 3 weeks of test period 56 patients (62%) were considered successful. Prolonged interventional testing increased cumulative success. A 1-year followup showed no significant difference in success rate between early responders and those in need for reprogramming (chi2, p=0.562). There was no difference in age (Mann-Whitney U, p=0.222), sex (chi2, p=0.952) or indication (chi2, p= 0.975). CONCLUSIONS: A 3-week test phase with close followup increases cumulative success rate. During this supervised 3-week test phase 42% of the initial nonresponders after the first week became successful candidates after reprogramming. Patients who required this additional programming did equally as well as those without need for reprogramming. A supervised 3-week test phase is therefore strongly recommended.

Device outcomes in pediatric sacral neuromodulation: A single center series of 187 patients.

INTRODUCTION: Pediatric sacral neuromodulation (SNM) device duration before revision or removal is not well known. Furthermore, secondary surgeries serve as surrogates for key outcomes including complications and symptom improvement. OBJECTIVE: We sought to study the rate and causes of secondary surgeries in pediatric SNM patients. STUDY DESIGN: We assessed our cohort of pediatric SNM patients for secondary surgeries (revision or removal). Baseline patient characteristics associated with secondary surgery were analyzed with Fisher's exact test. Kaplan-Meier analysis was used to describe secondary-surgery-free device survival. RESULTS: 187 pediatric patients underwent sacral neuromodulation at our institution between 2002 and 2019. 7 (4%) patients did not have a permanent device placed due to poor response during an externalized lead trial period, leaving 180 patients with permanent implanted devices. Over a median follow-up of 3.9 years (IQR 2.0 to 6.3), there were 154 total secondary surgeries. There were 83 device revisions, with 89% of revisions for a non-functioning device, 8% for pain, and 2% for infection. Of the non-functioning devices, 11% were due to battery depletion and the rest were due to lead fracture or dislodgement. Permanent device removal was performed in 71 (39%) patients, with 38% of these for unfavorable reasons (6% infection, 8% pain, 24% no longer effective) and 62% for favorable reasons (symptom improvement or resolution). Of patient baseline characteristics, only device duration was associated with favorable removal (p < 0.01). On Kaplan-Meier analysis, 5 year device secondary-surgery-free survival was 32% for any secondary surgery (favorable or unfavorable) and was 47% for unfavorable secondary surgery. At last follow-up, 74% of patients were in a favorable position (using the device, trialing with device off, or device had been removed for improvement) while 26% of patients were requiring other treatments due to device problem or removal. DISCUSSION: Describing the likelihood of subsequent surgery is an important aspect of patient and guardian counseling concerning pediatric SNM. Our cohort had a 68% 5 year all-cause reoperation rate. However, in a theoretical perfect world, pediatric SNM reoperation rate would be 100% after adequate follow-up (either for battery replacement, or device explantation for improvement). CONCLUSIONS: While sacral neuromodulation in our cohort of children carried a high (68% 5-year) reoperation rate (whether for complication or symptom improvement), the majority (74%) of these patients with previously refractory symptoms either continue to use their device or have had significant symptom improvement to permit device removal at moderate-term (median 3.9 year) follow-up.

Sleep disturbance changes in women after treatment of refractory overactive bladder with sacral neuromodulation.

Purpose: The aim of this study is to evaluate changes in sleep disturbance following treatment of overactive bladder with sacral neuromodulation. Materials and Methods: This is a sub-analysis of data collected from an institutional review board approved retrospective cohort study evaluating women with Patient-Reported Outcomes Measurement Information System-Sleep Disturbance (PROMIS-SD) before and after sacral neuromodulation for overactive bladder between March 2016 and October 2017. Data collected included demographics, clinical characteristics, and additional PROMIS item banks. Within-group analysis was performed with paired t-tests. Groups based up on PROMIS-SD improvement (change <0) were then compared using Fisher's exact test, t-test, or Mann-Whitney U-test as appropriate. Results: Those with improved sleep disturbance (n=7) noted a significant mean improvement of -3.99 (95% confidence interval, -6.32, -1.65; p<0.01). Both pre- and post-procedure PROMIS-Physical Function (38.86±2.35 vs. 34.13±5.58, p=0.07 and 37.14±5.10 vs. 35.44±4.74, p=0.53), Pain Interference (60.04±6.34 vs. 65.50±6.20, p=0.13 and 57.89±5.08 vs. 64.73±7.35, p=0.07), Depression (44.2±4.73 vs. 61.29±9.53, p=0.17 and 54.29±6.25 vs. 57.96±11.42, p=0.47) t-scores were similar between sleep response groups. Conclusions: Those with improved sleep disturbance reported significant changes after sacral neuromodulation for overactive bladder. However, no significant differences were identified between those with and without improvement. Further investigation of changes in sleep disturbance and factors affecting change are needed within this population.

Effectiveness of Neurostimulation Technologies for the Management of Chronic Pain: A Systematic Review.

OBJECTIVES: To describe the state of the literature for clinical effectiveness of neurostimulation used for the management of chronic pain. METHODS: A systematic review of spinal cord stimulation (SCS), peripheral nerve stimulation (PNS), peripheral nerve field stimulation (PNFS), and supraorbital transcutaneous electrical nerve stimulation in patients with cancer and noncancer chronic pain was conducted. MEDLINE, Embase, CINAHL, and the Cochrane CENTRAL Register of Controlled Trials were searched, using terms like "electrical stimulation therapy" and "pain management." Direction of effect, consistency across studies, and strength of evidence for effects of neurostimulation on chronic pain were narratively synthesized. RESULTS: A total of 15 randomized controlled trials (RCTs) examining SCS, 7 RCTs examining PNS/PNFS, and 1 nonrandomized trial examining supraorbital transcutaneous electrical nerve stimulation (TENS) were included. In nine SCS studies, neurostimulation had positive effects on pain. In three studies, neurostimulation did not significantly reduce pain. For PNS/PNFS, five studies found improvements in pain offered by neurostimulation; pain outcomes were not reported in two studies. In the TENS study, neurostimulation reduced headaches per month and medication consumption. Overall, 21 studies were of low or unclear risk of bias, 4 were high risk of bias, and the TENS study was not appropriate for assessment using the Cochrane Risk of Bias tool. CONCLUSIONS: A robust body of evidence examining SCS and PNS was identified. Only one study for PNFS and TENS was identified; both reported pain reductions. Generally, neurostimulation improved pain control. Future studies should examine the effectiveness of neurostimulation offered early in the trajectory of chronic pain.

Single Institutional Experience with Single Stage Sacral Neuromodulation: Cost Savings and Outcomes in a Contemporary Case Series.

PURPOSE: Sacral neuromodulation is traditionally performed in 2 stages. Studies have projected that 1-stage sacral neuromodulation is cost-effective if the conversion rate is 61.3% or greater. To our knowledge we present the first case series in the literature to evaluate the cost of 1-stage sacral neuromodulation. The objective of our study was to evaluate outcomes and analyze cost using our institutional experience with 1-stage sacral neuromodulation. MATERIALS AND METHODS: A total of 15 consecutive 1-stage sacral neuromodulation procedures were performed at a self-insured, integrated health care institution. Cost data were determined using 2019 Medicare reimbursement rates for CPT codes 64581, 64585, 64590 and 64595. Median operative time was derived from actual institutional data. RESULTS: One-stage sacral neuromodulation implantation was performed in 15 patients. Median followup was 14.6 months (IQR 6.9-22.5). Of the 15 cases 14 (93.3%) were successful, defined as a 50% or greater improvement from baseline. Total reimbursement for the 15 patients who underwent 1-stage implantation was $329,430. If these patients had undergone traditional 2-stage implantation with equivalent outcomes, the overall reimbursement was determined to be $414,796. Single-stage sacral neuromodulation implantation provided a calculated total cost savings of $85,366 (p <0.01). Moreover, a projected 233 minutes in operative time was saved by performing 1-stage sacral neuromodulation (p <0.01). CONCLUSIONS: This study demonstrates the potential health care savings of a 1-stage sacral neuromodulation procedure. Moreover, 1-stage sacral neuromodulation may have other added benefits, such as reduced infection rates, patient satisfaction and other indirect cost savings, including reduced time off from work.

[Sacral neuromodulation preliminary outcomes in male patients with idiopathic dysuria].

Objective: To assess the effectiveness and safety of sacral neuromodulation (SNM) therapy for men with idiopathic dysuria. Methods: From January 2012 to December 2016, a total of 26 patients treated with SNM therapy from multi-center across the country were retrospectively studied. The age ranged from 19 to 86 years with an average age of 45.2 years. Patients suffered from one or multiple urinary symptoms such as frequency of urination, urgency, urinary retention, etc. All patients had received more than two types of conservative therapy including oral and behavioral therapy, but had poor or no improvement. The voiding diary, urgency score and the quality of life score before implantation, in stageⅠ after implantation and stage Ⅱ after permanent implantation were recorded and compared. Results: A total of 22 patients chose to receive IPG at the end of stageⅠ therapy while 4 patients refused further stage Ⅱ therapy because of dissatisfactory effect. The conversion rate of stage Ⅰ to stage Ⅱ was 84.6% (22/26). The average follow-up time was 19.2 months, ranging from 3 to 63 months. The baseline of residual urine, voiding frequency and average voiding amount and those after stage Ⅰ therapy were [5 (0, 137.5) ] ml vs [0 (0, 40) ] ml, 14.6±6.1 vs 9.1±2.8, [100 (80, 135) ] ml vs [190 (150, 210) ] ml, respectively. The differences were statistically significant(all P<0.05).However, no significant differences were found in urination volume and quality of life (QoL) before and after implantation(P>0.05). During an average follow-up time of 19.2 months after the permanent implantation, over 80% patients had an improvement of residual urine volume by more than 50% after permanent implantation while the improvement was 55.6% after stage Ⅰ therapy, suggesting that the improvement of residual urine volume might be positively correlated with the duration of regulation. No significant differences were found in other parameters between stage Ⅰ and Ⅱ therapy. No adverse events like wound infection and electrode dislocation happened during our study. Conclusions: SNM is an effective and safety procedure for male patients with idiopathic dysuria, with a relatively high transfer rate. The medium-term curative effect is stable. The duration of regulation may be positively correlated with the improvement of residual urine.

What uro-gynecologists should know about sacral neuromodulation (SNM) for the treatment of refractory overactive bladder.

PURPOSE: To inform uro-gynecologists about the current standards and latest developments of sacral neuromodulation (SNM) in women with overactive bladder (OAB). METHODS: Literature search in the PubMed database for articles published between 1988 and 2019 on SNM for OAB in women. RESULTS: In total, 361 articles were identified and 51 articles retrieved for the review. SNM shows an objective success rate of 70-80%, OAB cure rate of 17-47% and a subjective satisfaction rate of 80-90%. These benefits have to be weighed against an adverse event rate of approx. 40%. SNM is significantly more successful than switching to another antimuscarinic after failed antimuscarinic drug therapy. Efficacy of SNM is slightly lower compared to bladder wall injections with 200 U botulinum toxin in the first months but efficacy of both treatments appears to be similar after 24 months. MRI examinations of patients with a sacral neurostimulator should only be performed after radiologist consultation. Sacral neurostimulators in patients with another pacemaker system should only be implanted after interdisciplinary consultation. The sacral neuromodulator should be turned off during pregnancy and delivery. SNM for OAB in patients with concomitant female sexual dysfunction or fecal incontinence seems to be beneficial. CONCLUSIONS: SNM is a successful and recommended second-line treatment of OAB. Sacral neurostimulators should preferably be implanted in SNM-centers because complications and the frequency of revisions are significantly reduced with increasing experience of the surgeon.

Specific Changes in Brain Activity during Urgency in Women with Overactive Bladder after Successful Sacral Neuromodulation: A Functional Magnetic Resonance Imaging Study.

PURPOSE: The mechanism of sacral neuromodulation is poorly understood. We compared brain activity during urgency before and after sacral neuromodulation in women with overactive bladder and according to the response to treatment. MATERIALS AND METHODS: Women with refractory overactive bladder who elected sacral neuromodulation were invited to undergo functional magnetic resonance imaging before and after treatment. During imaging the bladder was filled until urgency was experienced. Regions of interest were identified a priori and brain activity in these regions of interest was compared before and after treatment as well as according to the treatment response. Whole brain exploratory analysis with an uncorrected voxel level threshold of p <0.001 was also performed to identify additional brain regions which changed after sacral neuromodulation. RESULTS: Of the 12 women who underwent a pretreatment functional magnetic resonance imaging examination 7 were successfully treated with sacral neuromodulation and underwent a posttreatment examination. After sacral neuromodulation brain activity decreased in the left anterior cingulate cortex, the bilateral insula, the left dorsolateral prefrontal cortex and the bilateral orbitofrontal cortex (each p <0.05). No new brain regions showed increased activity after sacral neuromodulation. Pretreatment brain activity levels in the bilateral anterior cingulate cortex, the right insula, the bilateral dorsolateral prefrontal cortex, the right orbitofrontal cortex, the right supplementary motor area and the right sensorimotor cortex were higher in women who underwent successful treatment (each p <0.05). CONCLUSIONS: Brain activity during urgency changes after successful sacral neuromodulation. Sacral neuromodulation may be more effective in women with higher levels of pretreatment brain activity during urgency.

Onset of Action of Sacral Neuromodulation in Lower Urinary Tract Dysfunction-What is the Optimal Duration of Test Stimulation?

PURPOSE: Since the development of sacral neuromodulation, a large number of patients with lower urinary tract symptoms have been treated with this procedure. A test stimulation is performed prior to implantation. At centers worldwide the duration of this test stimulation varies considerably since it is not certain when the onset of the therapy effect can be expected. The objective of this prospective study was to evaluate the average onset time of sacral neuromodulation in patients with lower urinary tract symptoms. MATERIALS AND METHODS: All patients who were eligible for treatment with sacral neuromodulation were asked to participate in this study. A voiding diary was filled out prior to and during test stimulation using an implanted tined lead. Success was defined as a 50% or greater improvement compared to baseline in any of the main complaint parameters. The Mann-Whitney U test was used to compare the mean time to success between patients with overactive bladder syndrome and patients with nonobstructive urinary retention. RESULTS: Of the 45 patients 24 with nonobstructive urinary retention and 21 with overactive bladder syndrome agreed to participate and were included in study. Test stimulation was successful in 29 patients (64%). Mean time to success in all patients was 3.3 days (range 1 to 9). There was no significant difference in mean time to success between cases of overactive bladder syndrome and nonobstructive urinary retention (3.25 and 3.5 days, respectively, p = 0.76). CONCLUSIONS: The results imply that a test stimulation of more than 2 weeks is not necessary if a cutoff of 50% or greater improvement is adopted. However, further improvement can be expected with prolonged test stimulation. This might be important since it might have implications for long-term results.

Motor Response Matters: Optimizing Lead Placement Improves Sacral Neuromodulation Outcomes.

PURPOSE: We sought to determine the usefulness of motor responses during sacral neuromodulation lead placement by testing the hypothesis that a greater number of motor responses during intraoperative electrode testing would be associated with more durable therapy. MATERIALS AND METHODS: We retrospectively reviewed all sacral neuromodulation lead placements at a large academic center from 2010 to 2015. Included in study were all unilateral sacral lead placements for which the presence or absence of a motor response was documented discretely for each electrode. Motor responses were quantified into separate subscores, including bellows and toe response subscores (each range 0 to 4) for a possible maximum total score of 8 when combined. Revision surgery was the primary outcome. Univariate and multivariate analyses were performed for factors associated with lead revision. RESULTS: A total of 176 lead placements qualified for analysis. Mean ± SD cohort age was 58.4 ± 15.9 years, 86.4% of the patients were female and 93.2% had undergone implantation for overactive bladder. Median followup was 10.5 months (range 2 to 36). Overall 34 patients (19%) required lead revision. Revision was negatively associated with the total electrode response score (p = 0.027) and the toe subscore (p = 0.033) but not with the bellows subscore (p = 0.183). Predictors of revision on logistic regression included age less than 59 years at implantation (OR 5.5, 95% CI 2-14) and a total electrode response score less than 4 (OR 4.2, 95% CI 1.4-12.8). CONCLUSIONS: Fewer total electrode responses and specifically fewer toe responses were associated with sacral neuromodulation lead revision. These data suggest that placing a lead with more toe responses during testing may result in more durable sacral neuromodulation therapy.

Real-Time Changes in Brain Activity during Sacral Neuromodulation for Overactive Bladder.

PURPOSE: We performed functional magnetic resonance imaging to identify changes in brain activity during sacral neuromodulation in women with overactive bladder who were responsive to therapy. MATERIALS AND METHODS: Women recruited into the study had nonneurogenic refractory overactive bladder, responded to sacral neuromodulation and had had a stable program for at least 3 months with no subsequent overactive bladder treatment. Enrolled patients completed validated symptom and quality of life instruments before functional magnetic resonance imaging. Stimulus settings were recorded, devices were switched off for a 5-day washout and instruments were repeated. Three functional magnetic resonance imaging scans with simultaneous sacral neuromodulation stimulation were performed below, at and above stimulus sensory threshold using a block design. This yielded brain activity maps represented by changes in blood oxygenation level dependence. A total of 5 stimulator off and 4 stimulator on cycles of 42 seconds each were imaged. Group analysis was done using a single voxel p value of 0.05 with a false-positive error of 0.05 on cluster analysis. RESULTS: Six of the 13 patients enrolled completed functional magnetic resonance imaging. Median age was 52 years (range 36 to 64). Urinary symptoms and voiding diary data worsened with washout. Overall brain activation generally progressed with increasing stimulation amplitude. However, activation of the right inferior frontal gyrus remained stable while deactivation of the pons and the periacqueductal gray matter only occurred with subsensory stimulation. Sensory stimulation activated the insula but deactivated the medial and superior parietal lobes. Suprasensory stimulation activated multiple structures and the expected S3 somatosensory region. All devices had normal impedance after functional magnetic resonance imaging. CONCLUSIONS: Functional magnetic resonance imaging confirmed that sacral neuromodulation influences brain activity in women with overactive bladder who responded to therapy. These changes varied with stimulus intensity.