A pilot study to compare daily with twice weekly transcutaneous posterior tibial nerve stimulation for faecal incontinence

Long-term efficacy of percutaneous tibial nerve stimulation for faecal incontinence and a new approach for partial responders

BACKGROUND

The aim of the present study was to evaluate the long-term efficacy of percutaneous tibial nerve stimulation (PTNS) for patients with faecal incontinence (FI) refractory to conservative treatment. Secondary aims were to identify predictors of response and validate new treatment pathways for partial responders.

METHODS

A prospective, interventional study was carried out in a specialist defecatory disorder unit from a university hospital between January 2010 and June 2017 on patients > 18 years old with FI refractory to conservative treatment. Thirty-minute PTNS sessions were performed in three phases (weekly, biweekly and monthly) up to a year, with clinical reassessment at 3, 6, 12 and 36 months. Patients were classified as optimal responders when their pretreatment Wexner score decreased > 50%; partial responders when it decreased 25-50%; and insufficient responders if it decreased < 25%. Only optimal and partial responders progressed into successive phases.

RESULTS

Between 2010 and 2017, 139 patients (110 women, median age 63 years [range 22-82 years]) were recruited. After the first phase, 4 patients were optimal responders, 93 were partial responders and 36 were insufficient responders. At 6 and 12 months, 66 and 89 patients respectively were optimal responders, with an optimal response rate of 64% at the end of treatment. A total of 93.3% patients with a partial response initially finally became optimal responders. Furthermore, at 36 months, 71.9% of patients were still optimal responders without supplementary treatment, although their quality of life did not improve significantly. Baseline Wexner scores ≤ 10 and symptom duration < 1 year were identified as predictive factors for positive responses to PTNS.

CONCLUSIONS

Patients undergoing PTNS for 1 year following this protocol had optimal long-term responses. PTNS sessions for up to 1 year in patients who were partial responders prevents a high percentage of them from needing more invasive treatments, and maintains long-term continence in patients who were optimal responders.

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.

Tibial nerve stimulation increases vaginal blood perfusion and bone mineral density and yield load in ovariectomized rat menopause model

INTRODUCTION AND HYPOTHESIS

Human menopause transition and post-menopausal syndrome, driven by reduced ovarian activity and estrogen levels, are associated with an increased risk for symptoms including but not limited to sexual dysfunction, metabolic disease, and osteoporosis. Current treatments are limited in efficacy and may have adverse consequences, so investigation for additional treatment options is necessary. Previous studies have demonstrated that percutaneous tibial nerve stimulation (PTNS) and electro-acupuncture near the tibial nerve are minimally invasive treatments that increase vaginal blood perfusion or serum estrogen in the rat model. We hypothesized that PTNS would protect against harmful reproductive and systemic changes associated with menopause.

METHODS

We examined the effects of twice-weekly PTNS (0.2 ms pulse width, 20 Hz, 2× motor threshold) under ketamine-xylazine anesthesia in ovariectomized (OVX) female Sprague-Dawley rats on menopause-associated physiological parameters including serum estradiol, body weight, blood glucose, bone health, and vaginal blood perfusion. Rats were split into three groups (n = 10 per group): (1) intact control (no stimulation), (2) OVX control (no stimulation), and (3) OVX stimulation (treatment group).

RESULTS

PTNS did not affect serum estradiol levels, body weight, or blood glucose. PTNS transiently increased vaginal blood perfusion during stimulation for up to 5 weeks after OVX and increased areal bone mineral density and yield load of the right femur (side of stimulation) compared to the unstimulated OVX control.

CONCLUSIONS

PTNS may ameliorate some symptoms associated with menopause. Additional studies to elucidate the full potential of PTNS on menopause-associated symptoms under different experimental conditions are warranted.

Efficacy of Posterior Tibial Nerve Stimulation in the Treatment of Fecal Incontinence: A Systematic Review

Fecal incontinence is a condition that carries high social stigmatization and a determining factor in the quality of life of the person who suffers from it. Its etiology is multifactorial and treatment includes surgical and conservative measures, including stimulation of the posterior tibial nerve. The aim of this review is to determine whether posterior tibial nerve stimulation (PTNS) is more effective than other treatments in reducing episodes of fecal incontinence in adults. A systematic review of randomized clinical trials that analyzed different approaches and comparisons with other treatments in adults without neurological or metabolic diseases was carried out, analyzing, fundamentally, the reduction of episodes of fecal incontinence. In general, a reduction in fecal incontinence episodes is observed in the experimental groups compared with the control groups, although these differences are not significant in most studies. The results regarding the effectiveness of PTNS in reducing episodes of fecal incontinence compared to other treatments are not entirely conclusive, although benefits are observed regarding the stimulation of sacral roots. More well-designed studies with a long-term follow-up of the results are needed so that the recommendation of this treatment can be generalized.

Comparison of transcutaneous tibial nerve stimulation (TTNS) protocols for women with refractory overactive bladder (OAB): A prospective randomised trial

OBJECTIVES

Transcutaneous tibial nerve stimulation (TTNS) is a noninvasive method used in OAB treatment. Purpose of this study is to compare the effectiveness of the TTNS procedure applied once a week and three times a week in women diagnosed with wet type refractory OAB.

METHODS

A total of 60 patients diagnosed with wet type OAB that was refractory to medical treatment were included in the study. Participants were equally and randomly divided into two groups: TTNS treatment was performed with a duration of 30 minutes for 12 weeks, once a week to Group I and three times a week to Group II. Pretreatment and posttreatment OAB-V8/ICIQ-SF scores and voiding frequencies recorded in the bladder diary were compared between groups.

RESULTS

Four patients in Group 1 and eight in Group 2 left the study without completing the treatment. TTNS was performed in both groups for 12 weeks. There was a significant decrease in the voiding frequency, OAB-V8, ICIQ-SF scores in both group 1 and group 2 (P < .001). A significant decrease in the OAB-V8 score was observed in the 5th week in Group 1, and in the 3rd week in Group 2. Complete response was observed in 6 patients (23.1%) in Group 1 after 12 weeks of TTNS procedure. In Group 2, 10 patients (45.5%) had a complete response. After the 12-week TTNS procedure, no significant difference was observed between the groups in terms of treatment response.

CONCLUSION

TTNS can be safely used before invasive treatments in resistant OAB. TTNS procedure three times a week seems more effective than performing it once a week. What's known TTNS is one of the effective alternative treatments in resistant OAB treatment. What's new As the number of sessions is increased in TTNS treatment, the success of the treatment can increase.

Tools for fecal incontinence assessment: lessons for inflammatory bowel disease trials based on a systematic review

BACKGROUND

Fecal incontinence is a disabling condition affecting up to 20% of women.

OBJECTIVE

We investigated fecal incontinence assessment in both inflammatory bowel disease and non-inflammatory bowel disease patients to propose a diagnostic approach for inflammatory bowel disease trials.

METHODS

We searched on Pubmed, Embase and Cochrane Library for all studies on adult inflammatory bowel disease and non-inflammatory bowel disease patients reporting data on fecal incontinence assessment from January 2009 to December 2019.

RESULTS

In total, 328 studies were included; 306 studies enrolled non-inflammatory bowel disease patients and 22 studies enrolled inflammatory bowel disease patients. In non-inflammatory bowel disease trials the most used tools were the Wexner score, fecal incontinence quality of life questionnaire, Vaizey score and fecal incontinence severity index (in 187, 91, 62 and 33 studies). Anal manometry was adopted in 41.2% and endoanal ultrasonography in 34.0% of the studies. In 142 studies (46.4%) fecal incontinence evaluation was performed with a single instrument, while in 64 (20.9%) and 100 (32.7%) studies two or more instruments were used. In inflammatory bowel disease studies the Wexner score, Vaizey score and inflammatory bowel disease quality of life questionnaire were the most commonly adopted tools (in five (22.7%), five (22.7%) and four (18.2%) studies). Anal manometry and endoanal ultrasonography were performed in 45.4% and 18.2% of the studies.

CONCLUSION

Based on prior validation and experience, we propose to use the Wexner score as the first step for fecal incontinence assessment in inflammatory bowel disease trials. Anal manometry and/or endoanal ultrasonography should be taken into account in the case of positive questionnaires.

Update on Implantable PTNS Devices

PURPOSE OF REVIEW

There is growing evidence supporting the use of percutaneous tibial nerve stimulation to manage lower urinary tract symptoms (LUTS) such as urgency, frequency and urge incontinence, in a non-pharmacologic, minimally invasive approach. Given this, there is now an impetus to move this technology forward from an interval (i.e., weekly and/or monthly) toward a continuous dosing, using implantable devices. This review article focuses on the newest implantable devices and the most current data demonstrating safety and efficacy in the management of refractory overactive bladder.

RECENT FINDINGS

There are new studies showing that continuous (or even semi-continuous) stimulation of the tibial nerve can be of similar efficacy as other chronic neural implant devices, such as sacral neuromodulation. This includes the Blue Wind Renova, StimGuard, eCoin, and Bioness Stimrouter. While the data on these devices are still short-term, implantable tibial nerve stimulation holds promise in the field of managing LUTS and pelvic floor disorders. Durability and minimizing migration remain challenging.

What Is New in Neuromodulation?

Neuromodulation encompassing sacral and peripheral modalities is an established, effective, and safe higher-order treatment option approved in the USA for managing refractory overactive bladder, non-obstructive urinary retention, and fecal incontinence. This review highlights the most recent literature, indications, treatment durability, and the latest innovations in this field. Regarding sacral neuromodulation (SNM), recent work suggests improved parameters for optimal lead placement, increased data to support the lasting effects of treatment, and novel applications of this technology to other pelvic disorders. In addition, there are emerging technologies with smaller MRI compatible devices. Newer data on percutaneous tibial nerve stimulation (PTNS) suggests it may be more beneficial for certain patients. With new technology, implantable tibial nerve stimulators are ushering in a new frontier of nerve stimulation in the comfort of the patient's home.

Effectiveness of percutaneous tibial nerve stimulation in managing refractory constipation

AIM

Chronic constipation can be aetiopathogenically classified into slow transit constipation (STC), rectal evacuation difficulty (RED) or a combination (BOTH). Although the efficacy of percutaneous tibial nerve stimulation (PTNS) in faecal incontinence has been well proved, a current literature search identifies only one study which assessed its effect on constipation. We aimed to evaluate the effectiveness of PTNS in patients with different causes of constipation.

METHOD

Thirty-four patients [30 women, median age 50 (20-79) years] with constipation who had previously failed maximal laxative and biofeedback therapy participated in the study. All patients underwent a baseline radio-opaque marker transit study and anorectal physiology examination. All had 12 sessions of PTNS of 30 min per session. A fall in the Wexner constipation score to ≤15 or by ≥5 points was taken as the primary outcome. Secondary outcomes included the results of pre- and post- PTNS transit and anorectal physiology studies.

RESULTS

Eleven patients had STC, 14 had RED and nine had BOTH. A response was seen in four patients (1/11 STC, 2/14 RED and 1/9 BOTH). Comparing pre- and post- PTNS, there was no significant change in the mean Wexner score (P = 0.10). There was no change in colonic transit time among the whole population (P = 0.56) or among those with STC (P = 0.47). There was no improvement in balloon expulsion in the whole group (P = 0.73) or in patients with RED (P = 0.69).

CONCLUSION

PTNS is of no benefit to patients with constipation, whatever aetiopathogenic mechanism is responsible for the symptoms.

Posterior tibial nerve stimulation for the treatment of fecal incontinence: a systematic evidence review

IMPORTANCE AND OBJECTIVES

Posterior tibial nerve stimulation (PTNS) is a potential emerging therapy for fecal incontinence (FI). The aim of this study was to systematically review the literature regarding the efficacy of PTNS as a treatment of FI.

EVIDENCE ACQUISITION

We searched MEDLINE/PubMed, EMBASE, and Cochrane databases from inception through November 2013. We included English-language full-text articles reporting outcomes for FI with either percutaneous PTNS or transcutaneous techniques (transcutaneous electrical nerve stimulation). We used the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system to assess study quality.

RESULTS

Our search yielded 1154 citations; 129 abstracts and 17 articles were included for full-text review. There were 13 case series and 4 randomized controlled trials. Fifteen studies were of low quality, none were of fair quality, and 2 studies were of good quality based on the Grades of Recommendation, Assessment, Development, and Evaluation system. In total, 745 subjects were studied, and of those, 90% were women and 10% were men. Studies involved percutaneous PTNS in 57% (428/745) of the subjects, transcutaneous electrical nerve stimulation in 30% (223/745), and sham technique in 13% (94/745). Therapy frequency, maintenance therapy, and follow-up time varied across studies. Eleven studies assessed FI episodes and bowel movement deferment time; all but 1 showed statistical improvement after therapy. Ten of the 11 studies that used the Cleveland Clinic Florida Fecal Incontinence score reported statistically significantly improved scores after treatment.

CONCLUSIONS AND RELEVANCE

Multiple low-quality studies show improvement in FI after PTNS. High-quality studies with comparison groups and clinically meaningful outcome measures would further establish the utility of PTNS for FI.

Bilateral transcutaneous tibial nerve stimulation for chronic constipation

AIM

Chronic constipation is difficult to treat when symptoms are intractable. Colonic propulsion may be altered by distal neuromodulation but this is conventionally delivered percutaneously. Transcutaneous tibial nerve stimulation is noninvasive and cheap: this study aimed to assess its efficacy in chronic constipation.

METHOD

Eighteen patients (median age 46 years, 12 female) with chronic constipation were recruited consecutively. Conservative and behavioural therapy had failed to improve symptoms in all 18. Thirty minutes of daily bilateral transcutaneous tibial nerve stimulation was administered by each patient at home for 6 weeks. The primary outcome measure was a change in the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. Change in Patient Assessment of Constipation Symptoms (PAC-SYM), weekly bowel frequency and visual analogue scale (VAS) score were also measured.

RESULTS

Fifteen patients (12 female) completed the trial. The PAC-QoL score improved significantly with treatment [pretreatment, median 2.95, interquartile range (IQR) 1.18; posttreatment, median 2.50, IQR 0.70; P = 0.047]. There was no change in PAC-SYM score (pretreatment, median 2.36, IQR 1.59; posttreatment, median 2.08, IQR 0.92; P = 0.53). Weekly stool frequency improved as did VAS score, but these did not reach statistical significance (P = 0.229 and 0.161). The PAC-QoL and PAC-SYM scores both improved in four (26%) patients. Two patients reported complete cure. There were no adverse events reported.

CONCLUSION

Bilateral transcutaneous tibial nerve stimulation appears to be effective in a quarter of patients with chronic constipation. Carefully selected patients with less severe disease may benefit more. This requires further study.

Management of patients with faecal incontinence

Faecal incontinence, defined as the involuntary loss of solid or liquid stool, is a common problem affecting 0.8-8.3% of the adult population. Individuals suffering from faecal incontinence often live a restricted life with reduced quality of life. The present paper is a clinically oriented review of the pathophysiology, evaluation and treatment of faecal incontinence. First-line therapy should be conservative and usually include dietary adjustments, fibre supplement, constipating agents or mini enemas. Biofeedback therapy to improve external anal sphincter function can be offered but the evidence for long-term effect is poor. There is good evidence that colonic irrigation can reduce symptoms and improve quality of life, especially in patients with neurogenic faecal incontinence. Surgical interventions should only be considered if conservative measures fail. Sacral nerve stimulation is a minimally invasive procedure with high rate of success. Advanced surgical procedures should be restricted to highly selected patients and only performed at specialist centres. A stoma should be considered if other treatment modalities fail.

Short-term Outcomes of a Randomized Pilot Trial of 2 Treatment Regimens of Transcutaneous Tibial Nerve Stimulation for Fecal Incontinence

BACKGROUND

Fecal incontinence is a socially disabling condition that affects ≤15% of adults. Neuromodulatory treatments for fecal incontinence are now well established. Less invasive, cheaper, and more ambulatory forms of neuromodulation are under exploration.

OBJECTIVE

The purpose of this study was to assess the acceptability and safety of a new ambulatory tibial nerve stimulation device and to determine clinical effect size for 2 differing regimens of therapy.

DESIGN

This was a randomized, investigator-blinded, parallel-arm, 6-week pilot trial.

SETTINGS

The study was conducted at 7 United Kingdom trial centers. Patients were initially reviewed in the trial center, with subsequent applications of the device performed in the patients home setting.

PATIENTS

A total of 43 eligible patients (38 women) who failed conservative management of fecal incontinence were included in the study.

INTERVENTION

The study intervention involved twice-weekly, 1- versus 4-hour transcutaneous tibial nerve stimulation for 6 weeks (total of 12 treatments).

MAIN OUTCOME MEASURES

Standard fecal incontinence outcome tools (bowel diary, symptom severity score, and generic quality-of-life instruments) were used to collect data at baseline and at 2 weeks posttreatment cessation.

RESULTS

A total of 22 patients were randomly assigned to the 1-hour group and 21 to the 4-hour group. Improvements in fecal incontinence outcomes were observed for both groups, including median urge incontinence episodes per week at baseline and posttreatment (1-hour group 2.0 to 0.5 versus 4-hour group 4.0 to 1.0) and deferment time (1-hour group 2.0 to 2.0 minutes versus 4-hour group 0.5 to 5.0 minutes). Accompanying changes were observed in physical functioning domains of quality-of-life instruments. There were no adverse events, and the treatment was highly acceptable to patients.

LIMITATIONS

Limitations included the pilot design and lack of control arm in the study. Future trials would need to address these limitations.

CONCLUSIONS

This pilot study provides evidence that transcutaneous tibial nerve stimulation with a new ambulatory device is safe and acceptable for the management of fecal incontinence. Additional study is warranted to investigate clinical effectiveness.

Novel treatment options for fecal incontinence

Fecal incontinence (FI) is a devastating condition affecting a substantial portion of the population. The etiologies of FI are wide ranging, as are the treatment options. When conservative measures fail, often surgical intervention is required. As in any area where a wide range of treatment options exist, there is no one perfect solution. Fortunately, novel treatment options for FI are becoming available, namely, posterior tibial nerve stimulation, magnetic anal sphincter, stem cell transplant, pyloric transplantation, and acupuncture.

Posterior tibial nerve stimulation for fecal incontinence: Where are we?

Neurostimulation remains the mainstay of treatment for patients with faecal incontinence who fails to respond to available conservative measures. Sacral nerve stimulation (SNS) is the main form of neurostimulation that is in use today. Posterior tibial nerve stimulation (PTNS) - both the percutaneous and the transcutaneous routes - remains a relatively new entry in neurostimulation. Though in its infancy, PTNS holds promise to be an effective, patient friendly, safe and cheap treatment. However, presently PTNS only appears to have a minor role with SNS having the limelight in treating patients with faecal incontinence. This seems to have arisen as the strong, uniform and evidence based data on SNS remains to have been unchallenged yet by the weak, disjointed and unsupported evidence for both percutaneous and transcutaneous PTNS. The use of PTNS is slowly gaining acceptance. However, several questions remain unanswered in the delivery of PTNS. These have raised dilemmas which as long as they remain unsolved can considerably weaken the argument that PTNS could offer a viable alternative to SNS. This paper reviews available information on PTNS and focuses on these dilemmas in the light of existing evidence.