Low-Intensity Ultrasound Tibial Nerve Stimulation Suppresses Bladder Activity in Rats.

BACKGROUND AND OBJECTIVE: Noninvasive neuromodulation, particularly through low-intensity ultrasound, holds promise in the fields of neuroscience and neuro-engineering. Ultrasound can stimulate the central nervous system to treat neurologic disorders of the brain and activate peripheral nerve activity. The aim of this study is to investigate the inhibitory effect of low-intensity ultrasonic tibial nerve stimulation on both the physiological state and the overactive bladder (OAB) model in rats. MATERIALS AND METHODS: A total of 28 female Sprague-Dawley rats were used in this study. Continuous transurethral instillation of 0.9% normal saline into the bladder was initially performed to stimulate physiological bladder activity. Subsequently, a solution containing 0.3% acetic acid dissolved in saline was instilled to induce rat models of OAB. The study comprised two phases: initial observation of bladder response to low-intensity ultrasound (1 MHz, 1 W/cm2, 50% duty cycle) in seven rats; subsequent exploration of ultrasound frequency (3 MHz) and intensity (2 W/cm2 and 3 W/cm2) effects in 21 rats. The intercontraction intervals (ICIs) were the primary outcome measure. Histologic analysis of tibial nerves and surrounding muscle tissues determined safe ultrasound parameters. RESULTS: Low-intensity ultrasound tibial nerve stimulation significantly inhibited normal and OAB activity. Ultrasound stimulation at 1 MHz, 1 W/cm2, with a 50% duty cycle significantly prolonged the ICI in both normal (p < 0.0001) and OAB rats (p < 0.01), as did transitioning to a 3 MHz frequency (p = 0.001 for normal rats; p < 0.01 for OAB rats). Similarly, at an intensity of 2 W/cm2 and 1 MHz frequency with a 50% duty cycle, ultrasound stimulation significantly prolonged the ICI in both normal (p < 0.01) and OAB rats (p < 0.005). Furthermore, switching to a 3 W/cm2 ultrasound intensity also significantly extended the ICI in both normal (p < 0.05) and OAB rats (p = 0.01). However, after different ultrasound intensities and frequencies, there was no statistical difference in ICI ratios (preultrasound stimulation vs postultrasound stimulation/preultrasound stimulation ∗ 100%) in all rats (p > 0.05). Low-intensity ultrasound tibial nerve stimulation did not influence baseline pressure, threshold pressure, or maximum pressure. In addition, a latency period in bladder reflex inhibition was induced by low-intensity ultrasound tibial nerve stimulation in some rats. Histologic analysis indicated no evident nerve or muscle tissue damage or abnormalities. CONCLUSIONS: This study confirmed the potential of transcutaneous ultrasound tibial nerve stimulation to improve bladder function. According to the findings, the ultrasonic intensities ranging from 1 to 3 W/cm2 and frequencies of 1 MHz and 3 MHz are both feasible and safe treatment parameters. This study portended the promise of low-intensity ultrasound tibial nerve stimulation as a treatment for OAB and provides a basis and reference for future clinical applications.

New TENSI+ Device for Transcutaneous Posterior Tibial Nerve Stimulation: A Prospective, Multicentre, Post-market Clinical Study.

BACKGROUND AND OBJECTIVE: Our aim was to report the first clinical trial of TENSI+, a new device for transcutaneous posterior tibial nerve stimulation (TNS) for treatment of overactive bladder (OAB). METHODS: A prospective, multicentre clinical trial was conducted in adults with OAB in seven French centres. The main exclusion criteria were prior percutaneous or transcutaneous TNS or invasive OAB treatment, current antimuscarinic use, 24-h polyuria, known bladder disease, postvoid residual volume >150 ml, and pelvic organ prolapse stage >2. Patients self-administered daily TTNS sessions of 20 min with TENSI+ at home after education by a specialized nurse. A bladder diary, Urinary Symptom Profile and OAB-q questionnaires, and Patient Global Impression of Improvement (PGI-I) scores were evaluated at baseline and 3 and 6 mo. The primary endpoint was efficacy, based on PGI-I and variations in bladder diary parameters. Success was defined as a PGI-I score ≤3 and any improvement ≥30% in bladder diary parameters. KEY FINDINGS AND LIMITATIONS: The study included 78 patients (13 males). Nine patients had neurological disease, 21 had previously tried antimuscarinics, and 41 had wet OAB at baseline. At 3 mo, 65/78 patients had a full analysis set. Treatment was successful in 44/65 patients (67%), with 25/65 (38%) reporting both an objective improvement and high satisfaction. All OAB-related endpoints were significantly improved, except bladder capacity and total voided volume per 24 h. At 6 mo, only five of 44 patients had interrupted their treatment. No factor predictive of success was identified. Two adverse events (pain at stimulation site and/or pelvic pain) were reported and spontaneously resolved without treatment interruption. CONCLUSIONS AND CLINICAL IMPLICATIONS: TENSI+ is a safe and effective TTNS treatment option for OAB management. PATIENT SUMMARY: TENSI+ is a new device for nerve stimulation in patients with overactive bladder. Patients use the device at home every day. In our short-term trial, TENSI+ use improved symptoms in 67% of patients. Further evaluation over a longer period of time is needed.

Percutaneous tibial nerve stimulation versus sacral nerve stimulation for the treatment of faecal incontinence.

Introduction: Faecal incontinence (FI) is a common condition with a significant impact on quality of life (QoL). Neuromodulation treatments delivered by members of the multidisciplinary team including sacral nerve stimulation (SNS) and percutaneous tibial nerve stimulation (PTNS) are options for FI refractory to conservative management. The aim of this study was to assess whether a successful treatment with one neuromodulation modality corresponds with success in the other. Methods: A retrospective review of a prospectively managed neuromodulation database identified 15 patients who had undergone both PTNS and SNS. The definition of success of each treatment was a >50% improvement in any of The St. Mark's Incontinence Score, Manchester Health Questionnaire, or weekly faecal urgency or FI episodes. Results: Complete data from 12 patients was available for assessment and PTNS was delivered as the first treatment in nine patients. Overall, seven patients (58%) had successful PTNS treatment, with 10 (83%) having a successful SNS trials. Of the seven patients who had successful PTNS treatment, six patients (85.4%) went on to have success with SNS. Of the five patients who failed PTNS, four (80%) went on to have SNS success. Five (71%) of those who had positive PTNS outcomes had permanent SNS implantation as their final treatment decision. Conclusion: This study suggests that there is no clear relationship between successful PTNS treatment and an SNS trial period which may be explained by differing mechanisms of action or the potential placebo effect of PTNS. Further work is required to investigate any association in larger studies to inform clinical practice.

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

BACKGROUND: Chronic pelvic pain is a burdensome condition that involves multiple medical sub-specialties and is often difficult to treat. Sacral stimulation for functional bladder disease has been well established, but little large-scale evidence exists regarding utilization of other neuromodulation techniques to treat chronic pelvic pain. Emerging evidence does suggest that neuromodulation is a promising treatment, and we aim to characterize the use and efficacy of such techniques for treating chronic pelvic pain syndromes. MATERIALS AND METHODS: A systematic review of the literature demonstrating the treatment of chronic pelvic pain syndromes with neuromodulation. Abstracts were reviewed and selected for inclusion, including case series, prospective studies, and randomized controlled trials (RCTs). Case studies and publications in abstract only were not included. The reporting for this systematic review follows Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The literature search was performed using MEDLINE, Embase, Cochrane Library, PubMed, CINAHL, and Scopus. RESULTS: A total of 50 studies were included in this review, three of which were randomized controlled trials, and the remaining were prospective and retrospective case series. The range of pelvic pain conditions treated included interstitial cystitis, peripheral neuralgia, pudendal neuralgia, gastrointestinal pain, urogenital pain, sacroiliac joint pain, and visceral chronic pelvic pain. We reported on outcomes involving pain, functionality, psychosocial improvement, and medication reduction. CONCLUSIONS: Neuromodulation is a growing treatment for various chronic pain syndromes. Peripheral nerve stimulation was the least studied form of stimulation. Posterior tibial nerve stimulation appears to offer short-term benefit, but long-term results are challenging. Sacral nerve stimulation is established for use in functional bladder syndromes and appears to offer pain improvement in these patients as well. Dorsal root ganglion stimulation and spinal cord stimulation have been used for a variety of conditions with promising results. Further studies of homogeneous patient populations are necessary before strong recommendations can be made at this time, although pooled analysis may also be impactful.

Efficacy of a novel wearable transcutaneous tibial nerve stimulation device on bladder reflex compared to implantable tibial nerve stimulation in cats.

OBJECTIVE: To determine the efficacy of novel wearable transcutaneous tibial nerve stimulation (TTNS) device on bladder reflex in cats compared to implantable tibial nerve stimulation (ITNS). MATERIALS AND METHODS: Two self-adhesive electrodes of the TTNS device were placed at the left leg, and ITNS was applied to stimulate the tibial nerve of the right leg, respectively. The intensity threshold (T) was defined as inducing observable toe movement. Multiple cystometrograms (CMGs) with normal saline (NS) infusion were performed to determine the inhibitory effects of TTNS and ITNS on the micturition reflex. RESULTS: TTNS at 4 times T (4 T), 6 times T (6 T), and the maximum output current intensity 24 mA significantly increased the bladder capacity (BC) compared to the control level (8.70 ± 2.46 ml) (all p < 0.05); however, there was no statistical significance among the three intensities. At the same time, ITNS at 2 times T (2 T), 4 T, 6 T, and the current intension 24 mA could significantly increase the BC compared to the control level (all p < 0.05). Likewise, no significant difference was observed among the four intensities (p > 0.05). The T values of TTNS were higher than those of ITNS (p = 0.02). The inhibitory effects of TTNS and ITNS revealed no significant difference at their respective 2 T, 4 T, 6 T, and 24 mA. Neither TTNS nor ITNS changed the contraction duration and amplitude (all p > 0.05). CONCLUSIONS: TTNS was effective in increasing BC. The non-invasive neuromodulation technique could achieve a similar effect as ITNS.

OnabotulinumtoxinA discontinuation in patients with prior nerve stimulation.

PURPOSE: The objective of this study is to describe the characteristics of patients who discontinue onabotulinumtoxinA treatment for overactive bladder (OAB) and to determine the impact of prior sacroneuromodulation or peripheral nerve stimulation on the discontinuation rates of onabotulinumtoxinA. MATERIALS AND METHODS: This is a retrospective cohort study of women with at least two onabotulinumtoxinA (BTX-A) treatments for OAB with a Female Pelvic Medicine and Reconstructive surgeon at a referral center between January 2014 and July 2019. Patients were excluded if they underwent BTX-A treatment in the operating room or utilized clean intermittent catheterization at baseline. Women who continued injections throughout the study period were compared to those who did not. Discontinuation was defined as stopping BTX-A during the study period. Treatment failure was defined as a documented failure in the chart and/or moving to other OAB treatments. Loss to follow-up was defined as no follow-up greater than 12 months after the last injection. Discontinuation-free and failure-free survival were estimated by Kaplan-Meier analysis. RESULTS: A total of 214 women met the inclusion criteria with a mean age of 62.9 ± 14 years. Fifty percent were Black. Eighty-six (40.2%) discontinued onabotulinumtoxinA treatment during the study period. There were no demographic differences between patients who discontinued BTX-A and those who continued with the following exceptions: patients who discontinued had higher rates of prior pelvic reconstructive surgery (19.8% vs. 10.2%, p = 0.04) and were more likely to have the concurrent diagnosis of painful bladder syndrome (9.3% vs. 2.3%, p = 0.03). Patients diagnosed with a urinary tract infection (UTI) after ≥50% of treatments were more likely to discontinue (27.9% vs. 14.1%, p = 0.01). On multivariate logistic regression analysis, patients with recurrent UTIs after treatment were significantly more likely to discontinue than those who do not (odds ratio: 2.61, [1.17, 5.82]). Of the cohort, 54 (25%) patients had previously undergone nerve stimulation. A total of 27.8% of patients with prior nerve stimulation discontinued BTX-A compared to 44.4% of those without prior third line treatment (p = 0.03). Patients with prior nerve stimulation had a higher discontinuation-free survival rate (p = 0.013) but there was no difference in failure-free survival. CONCLUSIONS: Patients who have recurrent UTIs after onabotulinumtoxinA injections are 2.6 times more likely to discontinue treatment than those who do not have infections. Patients with prior exposure to nerve stimulation have a significantly lower onabotulinumtoxinA discontinuation rate, but there is no difference in failure rates.

Tibial nerve electrical stimulation for fecal incontinence: a systematic review and meta-analysis.

Tibial nerve stimulation (TNS) therapy is widely used to treat fecal incontinence (FI), but still, some controversy exists. This study aimed to determine whether TNS could improve FI from different evaluation angles. A systematic review and meta-analysis were conducted to provide indirect evidence of TNS treatment for FI. We searched for the original studies in PubMed, Embase, Web of Science, Ebsco Medline, Ovid Medline, and Cochrane Central Register of Controlled Trials published before November 31, 2021. The standardized mean difference was the efficacy analysis statistic, and the effect was expressed by the 95% confidence interval (CI). For the case series, we calculated the mean difference of the number of patients evaluated at baseline and last follow-up. Four randomized controlled trials (RCTs, four hundred and sixty participants) and eighteen case series (eight hundred and thirty-eight participants) were included in the study. The results of the RCTs showed that the number of weekly episodes of FI significantly reduced in the TNS group compared with the sham stimulation group. The results of the case series showed that TNS reduced the number of patients with FI per week. The Cleveland Clinic Florida FI Score significantly reduced. The post-treatment results of maximum squeeze pressure and maximum resting pressure were significantly different from baseline. This study showed that TNS to some extent reduced the number of patients with FI, reduced clinical symptoms, and improved anal physiological function. Despite the low quality of overall evidence, TNS still shows some potential as a safe treatment for FI.

Stimulation of the Tibial nerve Repetitively to Improve Incontinence in Parkinson's Electronically (STRIPE trial): a randomised control trial of tibial nerve stimulation for bladder symptoms in Parkinson's disease using a self-contained wearable device.

BACKGROUND: Bladder symptoms are common in Parkinson's disease (PD), affecting half of all individuals. These have significant impact on quality of life as well as implications for morbidity, contributing to falls and hospital admission. The treatment of bladder symptoms can be complicated by the tendency to side-effects in people with PD including cognitive impairment and gait instability with anti-muscarinics. The development of new, better treatments is therefore warranted. Tibial nerve stimulation is a form of neuromodulation demonstrated to improve overactive bladder symptoms in non-neurogenic cohorts. Previously requiring hospital attendance, we aim to explore the use of this intervention using a simple device that can be used by patients at home. METHODS: STRIPE is a phase II randomised control trial of tibial nerve stimulation delivered by the Geko™ device, a small, self-adhesive neuromuscular stimulation device currently used for thromboembolism prophylaxis post-surgery. Active tibial nerve stimulation will be compared to sham stimulation, with participants blinded to treatment allocation and undertaking outcome assessment whilst still blinded. Participants will be asked to self-administer stimulation at home twice per week, for 30 min per session, over the course of 3 months. Primary outcome measure will be the International Consultation on Incontinence Overactive Bladder Questionnaire (OAB) at week 12. Secondary outcomes will include pre- and post-intervention bladder diary (frequency, urgency episodes, nocturia), patient perception of global change, bowel function and bladder-related quality of life. Participants will be recruited from the Proactive Integrated Management and Empowerment (PRIME) cross-sectional trial in which participants have been screened for bladder symptoms and invited to take part, as well as clinician referral from around the region. DISCUSSION: This trial will involve a randomised control trial of a novel and easy to use method of delivering tibial nerve stimulation for PD in the patient's own home. This may potentially have huge benefit, avoiding the problems with side effects that can be seen with anti-muscarinics and providing a new potential modality of treatment. TRIAL REGISTRATION: ISRCTN11484954. Registered on 22 June 2021.

Posterior tibial nerve stimulation as a neuromodulation therapy in treatment of neurogenic overactive bladder in multiple sclerosis: A prospective randomized controlled study.

BACKGROUND: one of the major annoying disorders occurring in people with multiple sclerosis is lower urinary tract disorders (LUT). Urgency is considered the main one seriously influencing the quality of life. Neurogenic detrusor over activity (DOAB) is characterized by a hyperreflexic, overactive detrusor that responds quickly to low-intensity sensory input from general visceral afferent fibers. Overactivity has been claimed to induce random, uncontrolled contractions of the detrusor muscle, leading to intravesicular pressure rise, producing urgency, frequency, and consequently incontinence AIM: To demonstrate the therapeutic efficacy for posterior tibial nerve stimulation (PTNS) in neurogenic over active bladder (NOAB) in people with multiple sclerosis METHODS: The current trial is a prospective, randomized controlled study. Forty remitting relapsing males with MS with moderate NOAB symptoms were randomly assigned into two equal groups; control group (C) treated by selected therapeutic exercises program for strengthening pelvic floor muscles and an intervention group (ES) receiving an additional posterior tibial nerve electrical stimulation. Each session ranged from 45- 50 minutes, three days weekly for a month. Outcome measures were recorded before starting the treatment and after termination of the study intervention and included over active bladder symptoms score (OVBS) score, urodynamic parameters (uroflow, filling and voiding cystometry), and post voiding residual volume by abdominal ultrasound RESULTS: There was a significant improvement of all voiding parameters compared to baseline and the group C except frequency of urgency incontinence. A significant decrease was detected in post-treatment mean episodes number of nighttime frequency, urgency, urgency incontinence (1.65 ± 0.93, 1.2 ± 0.52 and 1.5 ± 0.76) respectively of the ES group compared to that of group C (3.05 ± 1.09, 2.25 ± 0.71 and 2.25 ± 1.06) (P < 0.01). There was a significant decrease in median post-treatment OVBS score 3 (3-3) compared to group C median score 5 (6-4). A statistically significant improvement was observed of all urodynamic parameters (bladder capacity and compliance, Detrusor overactivity (DO), maximum flow rate and post voidal residual volume in the ES group compared to the group C CONCLUSION: PTNS is a promising and potentially beneficial treatment option for NOAB symptoms in males with MS and superior to pelvic floor muscle training alone.

Comparison of the efficacy and safety of sacral root magnetic stimulation with transcutaneous posterior tibial nerve stimulation in the treatment of neurogenic detrusor overactivity: an exploratory randomized controlled trial.

Background: Both repetitive sacral root magnetic stimulation (rSMS) and transcutaneous posterior tibial nerve stimulation (TTNS) have demonstrated clinical benefits for lower urinary tract dysfunction. However it still remains unclear that which method is more effective and safer to treat neurogenic detrusor overactivity (NDO). Methods: From December 2020 to December 2021, 50 patients (31 men and 19 women, aged 47.9±12.4 years) with NDO secondary to suprasacral spinal cord injury (SCI) were enrolled and randomly allocated to the rSMS or TTNS group based on a computer-generated random numbers table. The stimulation was applied continuously 5 times per week for 20 sessions. Urodynamic test was conducted at baseline and the day after the final 20th treatment session. The primary outcome was the individual change (Δ) in maximum cystometric capacity (MCC) from baseline to post-treatment. Secondary outcomes included changes (Δ) for the following parameters: volume at 1st involuntary detrusor contraction (1st IDCV), maximal detrusor pressure (Pdetmax), bladder compliance (BC), postvoid residual (PVR) volume, and bladder voiding efficiency (BVE). Additionally, adverse reactions including pain and skin irritation during stimulation were observed and recorded as safety outcomes. Results: Finally 47 patients completed the study (23 in rSMS and 24 in TTNS group). A per-protocol (PP) analysis was performed, and Mann-Whitney U test and unpaired t-test were used for statistical analysis. Compared with the efficacy of TTNS, rSMS showed statistically greater ΔMCC [median +43 mL (IQR, 22-62 mL) vs. +20 mL (IQR, 15-25 mL), P=0.001, with a between-group difference of +22 mL (95% CI: +7 to +35 mL)] and ΔBVE [median +10.0% (IQR, 3.8-15.7%) vs. +3.5% (IQR, 0.0-7.8%), P=0.003, with a between-group difference of +5.9% (95% CI: +1.2% to +9.7%)]. No significant differences were found in Δ1st IDCV (P=0.40), ΔPdetmax (P=0.67), ΔBC (P=0.79) and ΔPVR (P=0.92) between the two groups. Meanwhile, patients exhibited high tolerance to both protocols, and no adverse reactions were observed. Conclusions: RSMS may be more effective to improve urodynamics in the treatment for NDO than TTNS, cause it led to a statistical improvement in bladder capacity and voiding efficiency, without any side effects. RSMS is thus worthy of further clinical promotion. Trial Registration: Chinese Clinical Trial Registry ChiCTR2100050663.

Efficacy of Tibial Nerve Stimulation on Fecal Incontinence in Patients With Low Anterior Resection Syndrome Following Surgery for Colorectal Cancer.

OBJECTIVE: To systematically review the available literature on the efficacy of tibial nerve stimulation on faecal incontinence and quality of life in adult patients with low anterior resection syndrome following surgery for colorectal cancer. METHODS: A primary search of electronic databases was conducted adopting a combination of search terms related to the following areas of interest: "efficacy", "tibial nerve stimulation" and "low anterior resection syndrome". A secondary search of the grey literature was performed in addition to checking the reference list of included studies and review papers. The review was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A descriptive analysis was used to integrate the review findings. RESULTS: Five distinct studies involving 116 patients met the inclusion criteria for the review. The included studies suggest that tibial nerve stimulation may have a positive effect on faecal incontinence and quality of life in some patients with low anterior resection syndrome and might be considered as an additional treatment option. CONCLUSION: There were a limited number of studies and a great degree of heterogeneity of evidence due to differences in participants' baseline characteristics, dropout rates, and follow-up periods. Further research adopting validated, consistent, and complex outcome assessment methods is recommended to determine the efficacy of tibial nerve stimulation for treatment of patients with low anterior resection syndrome.

Inhibitory effects of a smartphone-controlled wearable transcutaneous tibial nerve stimulation device on bladder reflexes in anesthetized cats.

OBJECTIVES: To explore the inhibitory effects of a novel, smartphone-controlled, and wearable tibial nerve stimulation device on nonnociceptive and nociceptive bladder reflexes in anesthetized cats and to compare the stimulus results of two current waveforms outputted by this new stimulator. MATERIALS AND METHODS: A novel, intelligent tibial nerve stimulator was put on the ankles of 14 cats and controlled by a mobile application. Cystometrograms (CMGs) were performed repeatedly by infusing 0.9% normal saline (NS) and 0.5% acetic acid (AA) through a urethral catheter. Inhibitory effects were explored by measuring the bladder capacity (BC) in two areas: (1) on nonnociceptive bladder reflex (infused with NS) and on nociceptive bladder reflex (filled with AA to induce overactive bladder [OAB] model); and (2) under the stimulation of two different current waveforms (waveforms A and B). RESULTS: In Group 1, the BC of AA-induced OAB (41.48 ± 8.40%) was significantly different compared with the capacity of a NS-infused bladder (104.89 ± 1.32%, p < 0.05). Both NS-filled (151.35 ± 5.71%, p < 0.05) and AA-instilled (71.41 ± 9.34%, p < 0.05) bladder volumes significantly increased after tibial nerve stimulation (TNS). In Group 2, the BC increased to 166.18 ± 15.17% (p = 0.026) and 127.64 ± 13.00% (p = 0.239), respectively, after TNS with waveforms A and B current. CONCLUSIONS: Results revealed that this novel, smartphone-based, wearable, and wireless tibial nerve stimulation system could inhibit the micturition reflex on physiological condition, serving as a potential option for OAB treatment. In addition, the waveforms of stimulation current had an important influence on the effects of TNS.

Efficacy of percutaneous and transcutaneous posterior tibial nerve stimulation on idiopathic overactive bladder and interstitial cystitis/painful bladder syndrome: A systematic review and meta-analysis.

OBJECTIVES: Percutaneous and transcutaneous posterior tibial nerve stimulation (PTNS and TTNS) showed a promising effect on overactive bladder (OAB) and interstitial cystitis/painful bladder syndrome. We aimed to give a systematic review and meta-analysis on the efficacy and safety of these therapeutic methods as well. METHODS: We searched studies available on PubMed, Embase, Cochrane, Scopus, Web of Science, and ProQuest on March 31, 2021, to find both published and unpublished studies. The retrieved articles were screened by two independent researchers and then the selected studies were critically appraised by Cochrane risk-of-bias tool for randomized trials, and Joanna Briggs Institute's checklist for quasi-experimental studies. Finally, the results of studies were synthesized using Review Manager (RevMan) 5.4 statistical software when the data were homogenous. The meta-analysis was performed by calculating the effect size (mean difference) and their 95% confidence intervals (CIs). RESULTS: Of the total 3194 publications, 68 studies were included in our qualitative evaluation and 9 studies (11 trials) in the quantitative stage. When TTNS or PTNS were compared to sham, placebo, no treatment, or conservative management, a decrease in frequency of urination was observed in both TTNS (mean difference [MD]: -3.18, 95% CI: -4.42 to -1.94, and p < 0.00001), and PTNS (MD: -2.84, 95% CI: -4.22 to -1.45, and p < 0.00001), and overall TTNS or PTNS (MD: -2.95, 95% CI: -4.01 to -1.88, and p < 0.00001). Significant improvements in mean voiding volume (MVV) and decreasing nocturia were also observed. CONCLUSIONS: Nerve stimulations either PTNS or TTNS appear to be effective interventions in treating refractory idiopathic OAB in terms of daily voiding frequency, MVV, urgency episodes, and nighttime voiding frequency. However, our result did not show any improvement in terms of urinary incontinence, postvoid residual volume or urge incontinence, and maximum cystometric capacity which emphasized the efficacy of these modalities on dry-OAB rather than wet-OAB.

Prolonged Inhibitory Effects of Repeated Tibial Nerve Stimulation on the Micturition Reflex in Decorticated Rats.

OBJECTIVE: This study aimed to determine whether a short-term repeated stimulation of tibial nerve afferents induces a prolonged modulation effect on the micturition reflex in a decorticated rat model. MATERIAL AND METHODS: Fifteen female Sprague-Dawley rats (250-350 g) were fully decorticated and paralyzed in the study. Tibial nerve stimulation (TNS) was delivered by inserting two pairs of needle electrodes close to the nerves at the level of the medial malleolus. Constant flow cystometries (0.07 mL/min) at approximately ten-minute intervals were performed, and the micturition threshold volume (MTV) was recorded and used as a dependent variable. After four to five stable recordings, the tibial nerves of both sides were stimulated continuously for five minutes at 10 Hz and at an intensity of three times the threshold for α-motor axons. Six same stimulations were applied repeatedly, with an interval of five minutes between each stimulation. Mean MTV was calculated on the basis of several cystometries in each half-hour period before, during, and after the six repeated TNS. RESULTS: During the experiment, all the animals survived in good condition with relatively stable micturition reflexes, and a significant increase in MTV was detected after TNS. The strongest effect (mean = 178%) was observed during the first 30 minutes after six repeated stimulations. This obvious threshold increase remained for at least five hours. CONCLUSIONS: A prolonged poststimulation modulatory effect on the micturition reflex was induced by short-term repeated TNS in decorticated rats. This study provides a theoretical explanation for the clinical benefit of TNS in patients with overactive bladder and suggests decorticated rats as a promising model for further investigation of the neurophysiological mechanisms underlying the bladder inhibitory response induced by TNS.

Novel botulinum neurotoxin-A tibial nerve perineural injection to alleviate overactive bladder symptoms in male rats.

Although tibial nerve modulation has shown to induce positive changes in the overactive bladder (OAB), prolonged therapeutic effects using percutaneous stimulation have not yet been achieved. Intradetrusor onabotulinum toxin A injection can provide prolonged therapeutic effects; however, its delivery requires invasive measures. By applying local relief of tibial nerve neural entrapment with onabotulinum toxin A injection, this study investigated the feasibility and efficacy of combining the abovementioned two therapeutic strategies. An OAB animal model was developed using 12 adult Sprague-Dawley rats with cyclophosphamide intraperitoneal injection. A perineural injection site comparable to the tibial nerve perineural injection site and corresponding to that in humans was identified and developed in rats. The toxin was injected five days after establishing the OAB. The incision was made in the skin on the lateral surface of the thigh. The biceps femoris muscle was cut across, exposing the sciatic nerve and its three terminal branches: the sural, common peroneal, and tibial nerves, and 100 units of onabotulinum toxin A was injected into the surrounding tissue. Five days following injection, cystometry was performed. Inter-contraction time, contraction pressure, and interval of the disease state improved with statistical significance. The OAB animal model showed significant improvement with the tibial nerve perineural injection of botulinum toxin, thereby suggesting the possibility of a comparable treatment adaptation in humans.

Overactive bladder: A review and update.

Overactive bladder syndrome is a chronic, disabling condition with physical, psychological and social consequences that significantly affects the quality of life of millions of patients worldwide. The economic impact of this disorder is crucial. Overactive bladder syndrome is a little-known condition, with different manifestations from patient to patient, which causes a great deal of frustration to the medical staff involved. The patient requires a clear explanation and the full support of the attending physician. It is extremely important to establish a correct diagnosis and an effective individualized treatment. The collaboration and understanding of these patients are extremely important aspects. Improving the quality of life in these patients is the main purpose in managing this condition. There are several treatment modalities that may be used progressively, with favorable albeit inconsistent results. This condition remains extremely challenging for specialists and, unfortunately, always one of maximum interest.

First-line treatment posterior tibial nerve stimulation in patients with interstitial cystitis/bladder pain syndrome.

INTRODUCTION: The aim of this study was to determine the effects of first-line treatment posterior tibial nerve stimulation (PTNS), applied once a week for a 12 week period, as a treatment modality for patients with Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). MATERIAL AND METHODS: A total of 39 female patients with IC/BPS were enrolled in the study. Patients had one 30-minute session of PTNS per week for 12 weeks and symptoms were assessed before and after the treatment sessions by the use of a voiding diary, visual analog scale (VAS) for pain, O'Leary-Sant interstitial cystitis symptom index (ICSI), and O'Leary-Sant interstitial cystitis problem index (ICPI). RESULTS: The mean age of the patients was 38.9 ±7.1 years. The improvements in voiding diary parameters after 12 weeks of PTNS treatment were statistically significant compared to baseline but the changes in nocturia, and average voiding volume were not statistically significant. Mean parametric improvements after 12 weeks of PTNS treatment compared to baseline included a daytime frequency decrease by 3.8 voids daily, urgency episodes decrease by 4.7 episodes daily, nocturia decrease by 0.3 voids and voided volume improvement by a mean of 8.4 ml. The difference for ICSI, ICPI and VAS between baseline and the 12th week of PTNS treatment scores demonstrated statistically significant improvements in pain severity, symptom and problem index. CONCLUSIONS: The findings in this study demonstrated the improvements of voiding diaries, ICSI, ICPI and VAS scores in patients with IC/BPS after 12 weeks PTNS. PTNS treatment is a beneficial firs-line treatment option to IC/BPS symptom amelioration.

Frequency-Dependent Effects on Bladder Reflex by Saphenous Nerve Stimulation and a Possible Action Mechanism of Tibial Nerve Stimulation in Cats.

PURPOSE: The present study determined the effects of saphenous nerve stimulation (SNS) at different stimulation frequencies on bladder reflex and explored a possible action mechanism of tibial nerve stimulation (TNS) on bladder activity in cats. METHODS: Two bipolar nerve cuff electrodes were implanted on the saphenous nerve and the contralateral tibial nerve in 13 cats, respectively. Multiple cystometrograms were obtained to determine the effects of single SNS at different frequencies and that of combined SNS and TNS on the micturition reflex by infusing normal saline. RESULTS: SNS at 1 Hz significantly reduced the bladder capacity (BC) to 59.8%±7.7% and 59.3%±5.8% of the control level at the intensity threshold (T) and 2T, respectively (P<0.05), while that at 20 Hz significantly increased the BC to 130.6%±4.2% of the control level at 6T (P<0.05). The TNS and SNS at 20 Hz did not significantly change the BCs at 1T (P>0.05), while combined stimulation at 1T significantly increased the BC to 122.7%±1.9% of the control level and induced an inhibitory effect which was similar to that TNS at 2T. CONCLUSION: The current study revealed that SNS reduced and increased BC depending on different stimulation frequencies. The combined SNS and TNS maximized the clinical efficacy at a low intensity. Also, SNS may be a potential therapeutic mechanism of TNS.

Randomized Crossover-Controlled Evaluation of Simultaneous Bilateral Transcutaneous Electrostimulation of the Posterior Tibial Nerve During Urodynamic Studies in Patients With Lower Urinary Tract Symptoms.

PURPOSE: Transcutaneous tibial nerve stimulation (TTNS) has proven to be a valuable treatment option for various lower urinary tract conditions, such as overactive bladder syndrome and neurogenic detrusor overactivity. The aim of this study was to investigate acute changes in urodynamic parameters due to bilateral TTNS. METHODS: Fifty-one patients (18-87 years; 61% female) with various lower urinary tract symptoms were enrolled in this study. They were single-blinded and randomly assigned to receive simultaneous bilateral TTNS either during their first urodynamic examination, followed by a second round using a placebo stimulation technique, or vice versa. RESULTS: For subjects without signs of anatomical pathologies, the filling volume at the first desire to void (FDV) increased significantly by 54 mL (interquartile range [IQR], 26-81 mL; P<0.01) under the influence of TTNS compared to placebo. The maximum cystometric capacity increased by 41 mL (IQR, 10-65 mL; P=0.02). The median micturition volume of patients with pathological postvoid residual volumes (>100 mL) increased by 76 mL compared to patients without urinary retention (IQR, 6-166 mL; P=0.03). CONCLUSION: Compared to placebo, simultaneous bilateral TTNS showed significant improvements in bladder functioning, such as delayed FDV, increased maximum cystometric capacity, and reduced urinary retention. Patients with signs of anatomical pathologies did not seem to benefit from TTNS. Further studies need to be conducted to compare the effectiveness of bilateral versus unilateral TTNS.

Percutaneous tibial nerve stimulation for the treatment of interstitial cystitis/bladder pain syndrome: a pilot study.

OBJECTIVES: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic pain condition that requires multimodal management. The American Urologic Association includes sacral neuromodulation in the treatment algorithm for refractory IC/BPS. We sought to determine the rate of overall symptom improvement of IC/BPS symptoms, using validated measures, after treatment with percutaneous tibial nerve stimulation (PTNS), a form of peripheral neuromodulation. METHODS: This was a single-arm, dual-center, pilot study examining a standard PTNS protocol in subjects with IC/BPS. Our primary outcome was subject response of "moderately" or "markedly improved" on the Global Response Assessment (GRA) scale after 12-weekly PTNS sessions. Assuming a 60% response rate, 24 subjects were needed to detect a response rate between 40 and 80% with 95% confidence. Secondary objectives included change in urinary frequency on a 24-h bladder diary, bladder pain as measured by VAS and responses to validated questionnaires for pelvic pain and IC/BPS. RESULTS: Of 21 subjects enrolled, 16 initiated and 10 completed the PTNS treatment course. The GRA response rate was 40% at week 6 and 30% at week 12. Seventy percent of the cohort had some degree of improvement. There were no adverse events. CONCLUSIONS: While only a minority of subjects with IC/BPS were responders to PTNS per GRA criteria, 70% of the cohort had some degree of improvement. Due to low recruitment and loss to follow-up, we did not achieve our predetermined significance. However, our promising findings add to the limited literature on this subject.