Acute Autonomic Nervous System Response to Direct Sacral Nerve Root Stimulation in Lower Urinary Tract Dysfunction: A New Approach to Understand the Mechanism of Action of Sacral Nerve Modulation.

PURPOSE: Our goal was to assess acute autonomic nervous system (ANS) response to direct sacral nerve root (SNR) stimulation in the context of lower urinary tract dysfunction. MATERIALS AND METHODS: In this retrospective monocentric study, patients undergoing 2-stage sacral nerve modulation for overactive bladder, nonobstructive urinary retention, or chronic bladder pain syndrome between March 2022 and June 2023 were analyzed. A standardized stimulation protocol was applied during the lead implantation, each of the 4 contact points being sequentially stimulated at the amplitude required to elicit anal motor response. Stimulations were labeled as StimA, StimB, StimC, and StimD, ordered by ascending order of minimum amplitude required for anal motor response. Heart rate variability parameters were collected using PhysioDoloris Monitor, and computed through the time-domain (standard deviation of normal-to-normal intervals [SDNN], root mean square of successive differences), the frequency-domain (low frequency, high frequency) and the graphical (Analgesia Nociception Index [ANI]) methods. RESULTS: Fifty patients were analyzed, including 35 females. Twelve patients had an underlying neurological disease. Efficacy was deemed achieved in 54% of patients. SDNN variability significantly increased during StimA to StimC, while maximum SDNN significantly increased only during StimA. ANI variability significantly increased during all 4 stimulations, while maximum ANI significantly increased only during StimA. CONCLUSIONS: Direct stimulation of SNR is responsible for a significant increase in ANS and relative parasympathetic nervous system activity, with a greater effect observed when the stimulation was delivered closer to the SNR. These results shed light on potential mechanisms underlying sacral nerve modulation, particularly regarding the treatment of ANS dysregulation in lower urinary tract dysfunction.

Radiation exposure of patients during endourological procedures.

PURPOSE: Considering the existing gaps in the literature regarding patient radiation dose (RD) and its associated risks, a systematic review of the literature on RD was conducted, focusing on percutaneous nephrolithotomy (PCNL), extracorporeal shock wave lithotripsy (SWL), and ureteroscopy (URS). METHODS: Two authors conducted a literature search on PubMed, Web of Science, and Google Scholar to identify studies on RD during endourological procedures. Two thousand two hundred sixty-six articles were screened. Sixty-five publications met the inclusion criteria using the PRISMA standards. RESULTS: RD was generally highest for PCNL, reaching levels up to 33 mSv, 28,700 mGycm2, and 430.8 mGy. This was followed by SWL, with RD reaching up to 7.32 mSv, 13,082 mGycm2, and 142 mGy. URS demonstrated lower RD, reaching up to 6.07 mSv, 8920 mGycm2, and 46.99 mGy. Surgeon experience and case load were inversely associated with RD. Strategies such as optimizing fluoroscopy settings, implementing ultrasound (US), and following the ALARA (As Low As Reasonably Achievable) principle minimized RD. CONCLUSIONS: This is the first systematic review analyzing RD, which was generally highest during PCNL, followed by SWL and URS. There is no specific RD limit for these procedures. Implementation of strategies such as optimizing fluoroscopy settings, utilizing US, and adhering to the ALARA principle proved effective in reducing RD. However, further research is needed to explore the factors influencing RD, assess their impact on patient outcomes, and establish procedure-specific reference levels for RD.

Radiation exposure of urologists during endourological procedures: a systematic review.

INTRODUCTION: Ionizing radiation is used daily during endourological procedures. Despite the dangers of both deterministic and stochastic effects of radiation, there is a lack of knowledge and awareness among urologists. This study reviewed the literature to identify the radiation exposure (RE) of urologists during endourological procedures. METHODS: A literature search of the Medline, Web of Science, and Google Scholar databases was conducted to collect articles related to the radiation dose to urologists during endourological procedures. A total of 1966 articles were screened. 21 publications met the inclusion criteria using the PRIMA standards. RESULTS: Twenty-one studies were included, of which 14 were prospective. There was a large variation in the mean RE to the urologist between studies. PCNL had the highest RE to the urologist, especially in the prone position. RE to the eyes and hands was highest in prone PCNL, compared to supine PCNL. Wearing a thyroid shield and lead apron resulted in a reduction of RE ranging between 94.1 and 100%. Educational courses about the possible dangers of radiation decreased RE and increased awareness among endourologists. CONCLUSIONS: This is the first systematic review in the literature analyzing RE to urologists over a time period of more than four decades. Wearing protective garments such as lead glasses, a thyroid shield, and a lead apron are essential to protect the urologist from radiation. Educational courses on radiation should be encouraged to further reduce RE and increase awareness on the harmful effects of radiation, as the awareness of endourologists is currently very low.

Response to tibial and sacral nerve modulation in overactive bladder: Is there any correlation?

OBJECTIVES: To assess the correlation between the response to transcutaneous tibial nerve stimulation (TTNS) and subsequent response to sacral nerve modulation (SNM) to treat overactive bladder (OAB). MATERIALS AND METHODS: All patients who consecutively received TTNS followed by a two-stage SNM between January 2016 and June 2022 to treat OAB in two university hospital centers were included. The response to each therapy was evaluated with success defined by a 50% or greater improvement in one or more bothersome urinary symptoms from baseline. The primary endpoint was the statistical relationship between the response to TTNS and the response to SNM, assessed by logistic regression. Secondary endpoints were the statistical relationship between the response to TTNS and the response to SNM when controlling for gender, age (<57 years vs. >57 years), presence of an underlying neurological disease, and presence of DO, adding the factor and interaction to the previous regression model. RESULTS: Among the 92 patients enrolled in the study, 68 of them were women (73.9%), and the median age was 57.0 [41.0-69.0] years. The success was reported in 22 patients (23.9%) under TTNS and 66 patients (71.7%) during the SNM test phase. There was no statistical correlation between response to TTNS and response to SNM in the overall population (confidence interval: 95% [0.48-4.47], p = 0.51). Similarly, there was no statistical correlation when controlling for age <57 years or ≥57 years, with p = 1.0 and p = 0.69, respectively. No statistical study could be conducted for the other subpopulations due to small sample sizes. CONCLUSION: The response to TTNS does not predict the response to SNM in the treatment of OAB. TTNS and SNM should be considered as separate therapies, and the decision-making process for OAB treatment should take this into account.

A prospective study to assess the effectiveness and safety of the BlueWind System in the treatment of patients diagnosed with urgency urinary incontinence.

BACKGROUND: Overactive bladder (OAB) affects one in six adults in Europe and the United States and impairs the quality of life of millions of individuals worldwide. When conservative management fails, third-line treatments including tibial neuromodulation (TNM) is often pursued. TNM has traditionally been accomplished percutaneously in clinic. OBJECTIVE: A minimally invasive implantable device activated by a battery-operated external wearable unit has been developed for the treatment of urgency urinary incontinence (UUI), mitigating the burden of frequent clinic visits and more invasive therapies that are currently commercially available. METHODS: A prospective, multicenter, single-arm, open-label, pivotal study evaluated the safety and effectiveness of the device in adult females with UUI (i.e., wet OAB) (BlueWind Implantable Tibial Neuromodulation [iTNM] system; IDE number #G200013; NCT03596671). Results with the device were previously published under the name RENOVA iStim, which has been since renamed as the Revi™ System. Approximately 1-month post-implantation of the device, participants delivered therapy at their convenience and completed a 7-day voiding diary before visits 6- and 12-months post-treatment initiation. The primary efficacy and safety endpoints were the proportion of responders to therapy ( ≥ 50% improvement on average number of urgency-related incontinence episodes) and incidence of adverse events from implantation to 12-month post-activation. RESULTS: A total of 151 participants, mean age 58.8 (SD: 12.5), were implanted; 144 and 140 completed the 6- and 12-month visits, respectively. The participants demonstrated mean baseline of 4.8 UUI/day (SD 2.9) and 10 voids/day (SD 3.3). Six and 12-months post-activation, 76.4% and 78.4% of participants, respectively, were responders to therapy in an intent-to-treat analysis. Of the 139 participants with completed 12-month diaries, 82% were responders, 50% were classified as "dry" (on at least 3 consecutive diary days), and 93.5% of participants reported that their symptoms improved. No implanted participant experienced an SAE related to the procedure or device. CONCLUSIONS: iTNM, delivered and powered by a patient-controlled external wearable communicating with an implant, demonstrated clinically meaningful and statistically significant improvement in UUI symptoms and a high safety profile. This therapy highlights the value of patient-centric therapy for the treatment of UUI.

Motor Response Matters: Lead Placement and Urologic Efficacy Linked in Sacral Neuromodulation.

OBJECTIVES: This study aimed to characterize the pelvic floor muscles (PFM) motor response provoked during sacral neuromodulation (SNM) lead placement, determining its utility in improving therapy delivery. MATERIALS AND METHODS: A prospective pilot study (January 2018-September 2021) was performed including patients with overactive bladder or nonobstructive urinary retention-a very homogeneous group without any medical history interfering with bladder function-who underwent SNM. An external pulse generator was connected for three weeks. Success was defined as ≥50% improvement. PFM electromyography was recorded using a multiple array probe. Differences in electrical PFM motor response (peak-to-peak amplitude, area under the curve [AUC] or latency) among different electrical stimulation levels up to 10V (and the clinically relevant intensities up to 3V) and different parts (four sides, three depths) of the pelvic floor were modeled using linear mixed model analysis (LMM). RESULTS: The study population comprised 26 women (overall success 81%). With increasing improvement in voiding diary data, higher peak-to-peak amplitudes and AUC were seen for up to 10V stimulation intensities (LMM: p value 0.0046 and 0.0043, respectively) and up to 3V stimulation intensities (LMM: p value 0.0261 and 0.0416, respectively). Subanalysis of the different parts of the PFM showed all different sides (first corrected p value < 0.0125) and depths (first corrected p value < 0.0167) presented with statistically significant differences in favor of those with higher percentage improvement for the 10V and 3V analyses, with only two exceptions: peak-to-peak amplitude at the posterior layer at the clinically relevant stimulation intensities (LMM: p value: 0.0752) and AUC at the posterior layer for the stimulation intensities on 10V (LMM: p value: 0.0557). No statistically significant differences were found for the overall mean peak-to-peak amplitude and AUC based on dichotomous outcome (responders vs nonresponders). CONCLUSIONS: Intraoperative PFM electromyography obtained during lead placement aids in more accurate targeting of the lead to the nerve. To our knowledge, this is the first study to correlate tined lead placement based on electrodiagnostic testing and outcome in SNM. It has been proved to be a reliable measurement tool, serving as a physiological biomarker of treatment response during the test phase. A strong motor response can make the surgeon confident that the correct position of the lead has been established for maximal benefit.

Burst Stimulation Evokes Increased Bladder and Urethral Pressure in Patients With Sacral Neuromodulation, Indicating Potential Activation of the Autonomic Nervous System: A Pilot Study.

OBJECTIVES: Currently, sacral neuromodulation (SNM) outcomes are often suboptimal, and changing stimulation parameters might improve SNM efficacy. Burst stimulation mimics physiological burst firing of the nervous system and might therefore benefit patients treated with SNM. The purpose of the present pilot study was to evaluate the effect of various Burst SNM paradigms on bladder and urethral pressure in patients with overactive bladder (OAB) or nonobstructive urinary retention (NOUR). MATERIALS AND METHODS: The bladder was filled to 50% of its capacity under general anesthesia in six patients with an implanted sacral lead for SNM purposes. Bladder pressure, and mid- and proximal urethral pressure were measured using conventional (Con-) SNM and various Burst SNM paradigms (10-20-40 Hz interburst frequency) with increasing amplitudes up to 5 mA for Con-SNM and 4 mA for Burst SNM. RESULTS: Burst SNM caused a substantial increase in both bladder and urethral pressure. In contrast, Con-SNM caused a milder increase in urethral pressure, and only one patient showed a modest increase in bladder pressure. Furthermore, the pressure increase was higher in the proximal urethra than in the midurethra using Burst-SNM, whereas Con-SNM caused comparable increases in proximal and midurethra pressure. CONCLUSIONS: Burst SNM induces bladder contraction compared with Con-SNM and induces higher pressure increases in bladder and proximal urethra than does Con-SNM in patients with OAB or NOUR, indicating a higher degree of autonomic nervous system stimulation. The observed responses could not be fully explained by the total charge of the Burst SNM paradigms, which suggests the importance of individual Burst SNM parameters, such as frequency and amplitude. Future studies should assess the feasibility and efficacy of Burst SNM in awake patients.

The effect of tranexamic acid on perioperative blood loss in transurethral resection of the prostate: A double-blind, randomized controlled trial.

BACKGROUND: Bleeding and bleeding-related complications remain common after bipolar transurethral resection of the prostate (TURP) for benign prostatic hyperplasia. This may possibly lead to prolonged postoperative irrigation, catheterization, and hospital stay. The objective of this trial was to evaluate the effect of high-dose tranexamic acid (TXA) on perioperative blood loss in patients treated with bipolar TURP for prostate sizes between 30 and 80 g. METHODS: We conducted a single-center, prospective, double-blind, randomized controlled trial. Eighty patients were screened for inclusion between March 2020 and January 2023. After exclusion, 65 patients were randomized in two comparable groups. The TXA group (31 patients) received a TXA intravenous loading dose of 10 mg/kg over 30 min before induction, followed by a maintenance dose of 5 mg/kg/h over 12 h. The placebo group (34 patients) received an equal dose of saline infusion. We measured age, weight, preoperative prostate size, anticoagulant use, 5-alpha reductase inhibitor use, preoperative urinary tract infection, American Society of Anesthesiologists score, difference in pre- and 24 h postoperative hemoglobin and hematocrit levels, operative time, resected adenoma weight, duration of postoperative irrigation, total amount of postoperative irrigation fluid, indwelling catheter time, duration of hospital stay, blood transfusion rate, and 4-week complication rate. RESULTS: Baseline characteristics in both groups were comparable. Postoperative hemoglobin decrease in TXA versus placebo group was 1 versus 1.6 mg/dL, respectively (p = 0.04). In addition, the amount of postoperative irrigation fluid (10.7 vs. 18.5 L), irrigation time (24.3 vs. 37.9 h), catheterization time (40.8 vs. 53.7 h), and hospital stay (46.9 vs. 59.2 h) were statistically significant in favor of TXA use. No blood transfusions were carried out. Four-week complication rate was comparable between the two groups. CONCLUSIONS: Perioperative high-dose TXA seems beneficial in reducing hemoglobin loss, postoperative irrigation, catheterization time, and hospital stay in bipolar TURP for prostate sizes between 30 and 80 g, without increased risk of TXA-related thromboembolic events.

Evolution of testicular asymmetry during puberty in adolescents without and with a left varicocele.

OBJECTIVES: To assess the evolution of the Testicular Atrophy Index (TAI) in adolescent boys with and without a left varicocele with special attention for the currently postulated cut-off value of 20%. SUBJECTS AND METHODS: During 2015-2019, 364 adolescent boys aged 11-16 years were recruited. Genital examination and scrotal ultrasonography were repeatedly performed (≥4 month intervals). Testicular volume (TV) was calculated using the Lambert formula (length × width × height × 0.71). TAI was calculated using the formula: [(TVright - TVleft)/TVlargest (right, left)] × 100. RESULTS: The final study population comprised 239 participants, 161 (67.36%) controls and 78 (32.64%) adolescent boys with left varicocele. The mean (sd) number of measurements per participant was 3.82 (1.08). A TAI of ≥20% at first measurement occurred in 9.94% and 35.90%, respectively. Of these, only 31.25% and 46.43% had a TAI of ≥20% at the last measurement, respectively. Nevertheless, the risk of ending up with a TAI of ≥20% was significantly higher if a TAI of ≥20% was recorded at first measurement (P = 0.041 and P = 0.002, respectively). The normalisation rate did not differ significantly between the groups (P = 0.182). Normalisation occurred most frequently in Tanner Stages III and IV. Normalisation was mostly (≥74%) due to catch-up growth of the left testis, in contrast to growth retardation of the right testis, in both groups. The TAI seems to be a fluctuating parameter. CONCLUSION: A TAI of ≥20% is a phenomenon seen in boys with and without varicocele but is more common in boys with varicocele. Although normalisation of a high TAI is frequently seen, both adolescent boys with and without a left varicocele who have an initial TAI of ≥20% have a higher risk of a TAI of ≥20% in the future. As the TAI is a fluctuating parameter during pubertal development, it's use as indicator for varicocelectomy based on a single measurement during pubertal development is questioned.

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.

The effect of prolapse surgery on voiding function.

INTRODUCTION AND HYPOTHESIS: Of women with symptomatic prolapse, 13-39% experience voiding dysfunction (VD). The aim of our observational cohort study was to determine the effect of prolapse surgery on voiding function. METHODS: Retrospective analysis of 392 women who underwent surgery between May 2005 and August 2020. All had a standardized interview, POP-Q, uroflowmetry and 3D/4D transperineal ultrasound (TPUS) pre-and postoperatively. Primary outcome was change in VD symptoms. Secondary outcomes were changes in maximum urinary flow rate (MFR) centile and post-void residual urine (PVR). Explanatory measures were change in pelvic organ descent as seen on POP-Q and TPUS. RESULTS: Of 392 women, 81 were excluded due to missing data, leaving 311. Mean age and BMI were 58 years and 30 kg/m2, respectively. Procedures performed included anterior repair (n = 187, 60.1%), posterior repair (n = 245, 78.8%), vaginal hysterectomy (n = 85, 27.3%), sacrospinous colpopexy (n = 170, 54.7%) and mid-urethral sling (MUS) (n = 192, 61.7%). Mean follow-up was 7 (1-61) months. Pre-operatively, 135 (43.3%) women reported symptoms of VD. Postoperatively, this decreased to 69 (22.2%) (p < 0.001), and of those, 32 (10.3%) reported de novo VD. The difference remained significant after excluding concomitant MUS surgery (n = 119, p < 0.001). Postoperatively, there was a significant decrease in mean PVR (n = 311, p < 0.001). After excluding concomitant MUS surgery, there was a significant increase in mean MFR centile (p = 0.046). CONCLUSIONS: Prolapse repair significantly reduces symptoms of VD and improves PVR and flowmetry.

Does Cystocele Type Vary Between Vaginally Parous and Nulliparous Women?

OBJECTIVES: To evaluate whether cystocele type varies with vaginal parity. METHODS: Retrospective analysis of 464 vaginally nulliparous women seen at 2 urogynecology units between November 2006 and November 2019. A control group consisted of 871 vaginally parous women seen between July 2017 and November 2019. Patients underwent a standardized interview, POPQ, urodynamic testing, and translabial ultrasound. On imaging, significant cystocele was defined as bladder descent to ≥10 mm below symphysis pubis. Volume datasets were analyzed offline and blinded against clinical data. RESULTS: Of 5266 women seen during the inclusion period, 464 were vaginally nulliparous. Three were excluded due to missing data, leaving 461. A control group of 871 parous women was generated from patients seen during the last 2.5 years of the inclusion period. Vaginally nulliparous women were presented at a younger age compared to vaginally parous women (P < .001). Symptoms of prolapse were reported in 104 (22%) nulliparae and 489 (56%) parous women (P < .0001). Vaginally parous women demonstrated more bladder descent (P < .0001) and more cystocele (418/871 versus 43/461, P < .0001), with a higher proportion of type III cystocele (cystocele with intact retrovesical angle) (20/43 versus 273/ 418, P < .0001). Cystourethrocele (Green type II) was more common in nulliparae and cystocele type III in parous women (P = .015). On multivariate analysis, these differences in proportions remained significant (P = .049). CONCLUSIONS: Nulliparity was associated with a higher proportion of Green type II cystoceles. Green type III cystocele was more common in vaginally parous women, suggesting that the latter may be more likely to be due to childbirth-related pelvic floor trauma.

Detailed Investigation of Bladder Diary Parameters During Sacral Neuromodulation in Patients With Overactive Symptoms.

AIMS: Sacral neuromodulation (SNM) is a well-accepted, minimally invasive modality for patients with overactive bladder (OAB). Successful response to SNM is defined as at least 50% improvement in key symptoms, evaluated in a bladder diary (BD). BDs provide much useful information on bladder behavior during daily life. The aim of this study is to investigate BD parameter changes during SNM therapy in patients with OAB. MATERIALS AND METHODS: The International Consultation on Incontinence Questionnaires (ICIQ)-BD was filled out by 34 patients with OAB, for three days at baseline and after three weeks of subthreshold sensory stimulation. The patients were considered responders for SNM when 50% improvement was seen in the BD. They underwent implantation of an internal pulse generator (IPG), and subsequently, an ICIQ-BD and a visual analog scale (VAS) evaluating bladder satisfaction during three days were filled out six weeks, six months, and one year after IPG implantation. RESULTS: IPGs were implanted in 29 patients (85%). The BD showed a significant decrease in 24-hour leakage at three weeks from 4.2 to 0.6 (-86%, p < 0.001), similar significant decreases at six weeks and six months, and at one year (-80%). Voided volume (VV) at corresponding bladder sensation codes was not different between baseline and at three weeks of tined-lead procedure (TLP) (p > 0.05), and at six weeks (p > 0.05), six months (p > 0.1), and one year of IPG (p > 0.08). After three weeks of TLP, urgency episodes decreased from 4.8 to 3.4 (-30%, p = 0.025), with 59% reduction at six-weeks IPG (p < 0.001) and 49% at six-months IPG (p = 0.013). At one year, a decrease from 4.7 to 2.3 (52% reduction, p = 0.017) was noted. VAS showed the strongest correlation with urgency (p < 0.001) and frequency (p = 0.006). No significant correlation was found with VV (p = 0.87). CONCLUSIONS: Our study describes how bladder sensation parameters change over time in patients on SNM. VV does not significantly increase, nor does frequency significantly decrease over the first year. Leaks and the percentage of urgency episodes significantly decrease, reaching a plateau level between six-weeks and six-months SNM.

Acceptability and perceived value of urodynamics from the patient perspective: A narrative review.

BACKGROUND: The value and application of urodynamic evaluation (UDS) have been a controversial topic in recent years. Gaining robust data on the patient viewpoint in this area is important since, even when UDS findings do not change the management plan, the objective diagnostic information gained from UDS may be valued by patients. Moreover, insights from UDS may empower treating physicians to counsel patients more effectively and manage their expectations regarding treatment outcomes. OBJECTIVE: This expert narrative review aims to analyze the findings of published studies in this area, looking at two topics in turn: (a) the tolerability and acceptability of the UDS procedure itself from the patient perspective and (b) patient perceptions of the clinical value of insights provided by UDS. DESIGN, SETTING, PARTICIPANTS, AND OUTCOME MEASUREMENTS: An evidence assessment was conducted using selected articles from the literature reporting data on patients' perspectives on the tolerability, acceptability, utility, and value of the urodynamic investigation. RESULTS AND LIMITATIONS: Although pain, discomfort, and infection risks are frequently used as a rationale to skip UDS when initial management fails, there is good evidence that, from the patients' perspective, the procedure is very well tolerated in most cases. There are only a few articles available that assess patient perceptions of the usefulness of UDS, but those that do exist appear to demonstrate that the insights gained from UDS are widely welcomed by patients in the interest of receiving a more tailored and personalized treatment approach. CONCLUSION: From the patient perspective, UDS appears to be a well-accepted and well-tolerated diagnostic tool in patients with lower urinary tract symptoms, particularly when an appropriate explanation is provided before the examination. Our review also highlights that patients value the objective information provided by UDS and that this outweighs the temporary invasiveness of the test. This information is particularly relevant in light of the relative lack of evidence in the literature about patient expectations of specialist care in functional urology, which may have hindered progress with quality of care.

Early interventions to prevent lower urinary tract dysfunction after spinal cord injury: a systematic review.

STUDY DESIGN: Systematic review. OBJECTIVES: To synthetise the available scientific literature reporting early interventions to prevent neurogenic lower urinary tract dysfunction (NLUTD) after acute supra-sacral spinal cord injury (SCI). METHODS: The present systematic review is reported according to the PRISMA guidelines and identified articles published through April 2021 in the PubMed, Embase, ScienceDirect and Scopus databases with terms for early interventions to prevent NLUTD after SCI. Abstract and full-text screenings were performed by three reviewers independently, while two reviewers performed data extraction independently. An article was considered relevant if it assessed: an in-vivo model of supra-sacral SCI, including a group undergoing an early intervention compared with at least one control group, and reporting clinical, urodynamic, biological and/or histological data. RESULTS: Of the 30 studies included in the final synthesis, 9 focused on neurotransmission, 2 on the inflammatory response, 10 on neurotrophicity, 9 on electrical nerve modulation and 1 on multi-system neuroprosthetic training. Overall, 29/30 studies reported significant improvement in urodynamic parameters, for both the storage and the voiding phase. These findings were often associated with substantial modifications at the bladder and spinal cord level, including up/downregulation of neurotransmitters and receptors expression, neural proliferation or axonal sprouting and a reduction of inflammatory response and apoptosis. CONCLUSIONS: The present review supports the concept of early interventions to prevent NLUTD after supra-sacral SCI, allowing for the emergence of a potential preventive approach in the coming decades.

The Influence of Electrode Configuration Changes on the Sensory and Motor Response During (Re)Programming in Sacral Neuromodulation.

OBJECTIVES: This study aimed to assess the neurophysiological basis behind troubleshooting in sacral neuromodulation (SNM). Close follow-up of SNM patients with program parameter optimization has proven to be paramount by restoring clinical efficacy and avoiding surgical revision. MATERIALS AND METHODS: A total of 34 successful SNM patients (28 overactive bladder wet, six nonobstructive urinary retention) with an implantable pulse generator were included. All possible bipolar and monopolar electrode settings were tested at sensory threshold (ST) to evaluate sensory (mapped on a perineal grid with 1 cm2 coordinates) and motor (peak-to-peak amplitude and latency of muscle action potential) responses of the pelvic floor. Pelvic floor muscle electromyography was recorded using a multiple array probe, placed intravaginally. Parametric tests were used for paired data: repeated-measures ANOVA or t-test. A nonparametric test was used for paired data: Friedman ANOVA or Wilcoxon signed rank (WSR) test; p < 0.05 was considered statistically significant. If significant, ANOVA was followed by Dunn-Bonferroni post hoc analysis. RESULTS: Monopolar configurations showed significantly lower STs-1.38 ± 0.73 V vs 1.76 ± 0.89 V (paired t-test: p < 0.0001)-and presented with significantly higher peak-to-peak amplitudes-115.67 ± 79.03 µV vs 90.77 ± 80.55 µV (WSR: p = 0.005)-than bipolar configurations. When polarity was swapped, configurations with the cathode distal to the anode showed significantly lower STs, 1.73 ± 0.91 V vs 1.85 ± 0.87 V (paired t-test: p = 0.003), and mean peak-to-peak amplitudes, 81.32 ± 72.82 µV vs 100.21 ± 90.22 µV (WSR: p = 0.0001). Cathodal changes resulted in more changes in sensory responses than anodal changes (χ2 test: p = 0.044). In cathodal changes only, peak-to-peak amplitudes were significantly higher when the distance between electrodes was maximally spread (WSR: p = 0.046). CONCLUSIONS: From a neurophysiological point of view, monopolar configurations stimulated more motor nerve fibers at lower STs, therefore providing more therapeutic efficiency. Swapping polarity or changing the position of the cathode led to different sensory and motor responses, serving as potential reprogramming options.

Sacral Neuromodulation Changes Pelvic Floor Activity in Overactive Bladder Patients-Possible New Insights in Mechanism of Action: A Pilot Study.

OBJECTIVES: To evaluate if electrodiagnostic tools can advance the understanding in the effect of sacral neuromodulation (SNM) on pelvic floor activity, more specifically if SNM induces changes in pelvic floor muscle (PFM) contraction. MATERIALS AND METHODS: Single tertiary center, prospective study (October 2017-May 2018) including patients with overactive bladder syndrome undergoing SNM. Electromyography of the PFM was recorded using the Multiple Array Probe Leiden. The procedure consisted of consecutive stimulations of the lead electrodes with increasing intensity (1-3, 5, 7, 10 V). Recordings were made after electrode placement (T0) and three weeks of SNM (T1). Patients with >50% improvement were defined as responders, others as nonresponders. For the analyses, the highest electrical PFM response (EPFMR), defined as the peak-to-peak amplitude of the muscle response, was identified for each intensity. The sensitivity (intensity where the first EPFMR was registered and the normalized EPFMR as percentage of maximum EPFMR) and the evolution (EMFPR changes over time) were analyzed using linear mixed models. RESULTS: Fourteen patients were analyzed (nine responders, five nonresponders). For nonresponders, the PFM was significantly less sensitive to stimulation after three weeks (T0: 1.7 V, T1: 2.6 V). The normalized EPFMR was (significantly) lower after three weeks for the ipsilateral side of the PFM for the clinically relevant voltages (1 V: 36%-23%; p = 0.024, 2 V: 56%-29%; p = 0.00001; 3 V: 63%-37%; p = 0.0002). For the nonresponders, the mean EPFMR was significantly lower at 8/12 locations at T1 (T0: 109 µV, T1: 58 µV; mean p = 0.013, range <0.0001-0.0867). For responders, the sensitivity and evolution did not change significantly. CONCLUSIONS: This is the first study to describe in detail the neurophysiological characteristics of the PFM, and the changes over time upon sacral spinal root stimulation, in responders and nonresponders to SNM. More research is needed to investigate the full potential of EPFMR as a response indicator.

Diagnosis and treatment of pudendal and inferior cluneal nerve entrapment syndrome: a narrative review.

AIM: Pudendal and inferior cluneal nerve entrapment can cause a neuropathic pain syndrome in the sensitive areas innervated by these nerves. Diagnosis is challenging and patients often suffer several years before diagnosis is made. The purpose of the review was to inform healthcare workers about this disease and to provide a basis of anatomy and physiopathology, to inform about diagnostic tools and invasive or non-invasive treatment modalities and outcome. METHODS: A description of pudendal and inferior cluneal nerve anatomy is given. Physiopathology for entrapment is explained. Diagnostic criteria are described, and all non-invasive and invasive treatment options are discussed. RESULTS: The Nantes criteria offer a solid basis for diagnosing this rare condition. Treatment should be offered in a pluri-disciplinary setting and consists of avoidance of painful stimuli, physiotherapy, psychotherapy, pharmacological treatment led by tricyclic antidepressants and anticonvulsants. Nerve blocks are efficient at short term and serve mainly as a diagnostic tool. Pulsed radiofrequency (PRF) is described as a successful treatment option for pudendal neuralgia in patients non-responding to non-invasive treatment. If all other treatments fail, surgery can be offered. Different surgical procedures exist but only the open transgluteal approach has proven its efficacy compared to medical treatment. The minimal-invasive ENTRAMI technique offers the possibility to combine nerve release with pudendal neuromodulation. CONCLUSIONS: Pudendal and inferior cluneal nerve entrapment syndrome are a challenge not only for diagnosis but also for treatment. Different non-invasive and invasive treatment options exist and should be offered in a pluri-disciplinary setting.

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.

Two-year outcomes of the ARTISAN-SNM study for the treatment of urinary urgency incontinence using the Axonics rechargeable sacral neuromodulation system.

AIMS: Sacral neuromodulation (SNM) is a guideline-recommended treatment with proven therapeutic benefit for urinary urgency incontinence (UUI) patients. The Axonics® System is the first Food and Drug Administration-approved rechargeable SNM system and is designed to deliver therapy for a minimum of 15 years. The ARTISAN-SNM study was designed to evaluate UUI participants treated with the Axonics System. Two-year follow-up results are presented. METHODS: One hundred and twenty-nine UUI participants underwent implantation with the Axonics System. Therapeutic response rate, participant quality of life (QoL), and satisfaction were determined using 3-day voiding diaries, ICIQ-OABqol, and satisfaction questionnaires. Participants were considered responders if they had a 50% or greater reduction in UUI episodes post-treatment. As-treated and Completers analyses are presented. RESULTS: At 2 years, 93% of the participants (n = 121 Completers at 2 years) were therapy responders, of which 82% achieved ≥ 75% reduction in UUI episodes and 37% were dry (100% reduction). Daily UUI episodes reduced from 5.6 ± 0.3 at baseline to 1.0 ± 0.2 at 2 years. Statistically significant improvements in ICIQ-OABqol were reported. All participants were able to recharge their device and 94% of participants reported that the recharging frequency and duration were acceptable. Participant demographics nor condition severity were correlated with clinical outcomes or recharging experience. No unanticipated or serious device-related adverse events occurred. CONCLUSIONS: At 2 years, participants treated with the Axonics System demonstrated sustained safety and efficacy, high levels of satisfaction with therapy and recharging. Participant-related factors were not associated with efficacy or recharging outcomes, indicating the reported results are applicable to a diverse population.