Neuromodulation for fecal incontinence: outcome in 16 patients with definitive implant. The initial Italian Sacral Neurostimulation Group (GINS) experience

[Therapeutic value of neuromodulation in women]

BACKGROUND

Neuromodulative treatment for the treatment of overactive bladder has been used in clinical practice since its introduction in the early 1980s.

OBJECTIVES

Description and update of the various neuromodulative techniques (tibial nerve stimulation, sacral and pudendal neuromodulation), presentation of their effectiveness and safety, and evaluation of their evidence for clinical practice.

MATERIALS AND METHODS

Literature search in PubMed and Embase, inclusion of studies according to the following criteria: evidence level, timeliness, length of follow-up and number of female patients according to the author's preference.

RESULTS

The efficacy and safety of both percutaneous tibial nerve stimulation (PTNS) and sacral neuromodulation (SNM) has been proven by studies with an evidence level of 1. Long-term data of up to 20 years are available for SNM, while long-term data for PTNS are limited. Permanent implants for tibial nerve stimulation are promising new developments. Pudendal neuromodulation (PNM) is suitable for more complex indications but is surgically more challenging.

CONCLUSIONS

Both PTNS and SNM are suitable for broad application in clinical practice. PTNS can be offered as an alternative to pharmacotherapy, while SNM provides the most convincing clinical data of all neuromodulative therapies.

Electroacupuncture Improves Voiding Function in Patients with Neurogenic Urinary Retention Secondary to Cauda Equina Injury: Results from a Prospective Observational Study

Objective

To report the therapeutic effectiveness and feasibility of electroacupuncture (EA) treatment in patients with urinary retention which is caused by cauda equina injury and refractory to conventional conservative treatments.

Methods

From 9 August 2007 to 10 May 2010 prospective evaluation was carried out in 15 patients with neurogenic urinary retention secondary to cauda equina injury who underwent EA treatment at bilateral points BL32, BL33 and BL35. All patients received five sessions of EA treatment each week for the first 4 weeks, three sessions a week for the following 2 weeks, and then were followed up for 6 months. Voiding abilities, postvoiding residual urine volume (RUV) and maximum urinary flow rate (Qmax) were documented as outcome measures.

Results

After 6 weeks’ EA treatment, 10/15 enrolled patients regained their self-voiding ability, and the mean postvoiding RUV for all patients decreased by 303.6±148.8 ml. In nine patients with documented data, Qmax increased by 11.0±6.3 ml/s. In nine patients, voiding difficulties changed from severe to mild. At the end of 6 months’ follow-up, 8/10 patients retained their regained self-voiding ability, whereas two patients had lost their voiding ability again.

Conclusion

The results indicate that the EA treatment may have longlasting therapeutic effectiveness in the management of neurogenic urinary retention secondary to cauda equina injury.

Advances in the Surgical Treatment of Fecal Incontinence

Although surgery for fecal incontinence has been shown to be effective, it is still very challenging and sometimes frustrating. Overlapping sphincteroplasty, by far the most common procedure, is effective in patients with sphincter defects; however, recent data suggest that success rates tend to deteriorate over time. A thorough preoperative evaluation incorporates numerous factors, including patient characteristics, severity of incontinence, type and size of the sphincter defect as assessed by physical examination, anal ultrasound, and anorectal physiology studies including anal manometry, electromyography, and pudendal nerve terminal motor latency assessment. The use of these evaluation methods has allowed better patient assignment for a variety of new alternative treatment options. Innovations in the surgical treatment of fecal incontinence range from simple, office-based sphincter augmentation techniques to surgical implantation of mechanical devices. This article reviews 5 alternative surgical treatment options for fecal incontinence: injection of carbon-coated beads in the submucosa of the anal canal, radiofrequency energy delivery, stimulated graciloplasty, artificial bowel sphincter, and sacral nerve stimulation.

Systematic review of the impact of sacral neuromodulation on clinical symptoms and gastrointestinal physiology

Background

Sacral neuromodulation (SNM) has emerged as a treatment option for faecal incontinence (FI). However, its objective effect on symptoms and anorectal function is inconsistently described. This study aimed to systematically review the impact of SNM on clinical symptoms and gastrointestinal physiology in patients with FI, including factors that may predict treatment outcome.

Methods

An electronic search of MEDLINE (1946–2014)/EMBASE database was performed in accordance with PRISMA guidelines. Articles that reported the relevant outcome measures following SNM were included. Clinical outcomes evaluated included: frequency of FI episodes, FI severity score and success rates. Its impact on anorectal and gastrointestinal physiology was also evaluated.

Results

Of 554 citations identified, data were extracted from 81 eligible studies. Meta‐analysis of the data was precluded due to lack of a comparison group in most studies. After permanent SNM, ‘perfect’ continence was noted in 13–88% of patients. Most studies reported a reduction in weekly FI episodes (median difference of the mean −7.0 (range: −24.8 to −2.7)) and Wexner scores (median difference of the mean −9 (−14.9 to −6)). A trend towards improved resting and squeeze anal pressures and a reduction in rectal sensory volumes were noted. Studies failed to identify any consistent impact on other physiological parameters or clinicophysiological factors associated with success.

Conclusion

SNM improves clinical symptoms and reduces number of incontinence episodes and severity scores in patients with FI, in part by improving anorectal physiological function. However, intervention studies with standardized outcome measures and physiological techniques are required to robustly assess the physiological impact of SNM.

Long-term results following sacral nerve stimulation for chronic constipation

AIM

The long-term outcome of sacral nerve stimulation (SNS) for chronic functional constipation was assessed.

METHOD

Patients who received a definitive SNS implant for chronic functional constipation only (according to the Rome III criteria) and were followed up for at least 3 years were included in this study. Slow transit constipation (STC) was distinguished from obstructed defaecation (OD) and mixed/undetermined constipation (MU). Constipation features, Cleveland Clinic Constipation score (CCCS) and SF-36 questionnaire data were collected; physiological tests were performed.

RESULTS

Forty-two out of 61 patients suitable for SNS received a definitive implant (14 for STC, 15 for OD, 13 for MU). Following SNS device implantation (mean follow-up 51 ± 15 months), the baseline CCCS (17 ± 6) dropped to 9 ± 6 (P < 0.001) and 47% of patients had an improvement in the CCCS of more than 50%. Such improvement was more significant in patients with OD. Anal pressures did not change, while threshold and urgency rectal sensation significantly decreased, in particular in patients with OD. All aspects of patients' health status (SF-36) improved significantly following SNS; this was more marked in patients with OD.

CONCLUSION

Data from this study suggest that the clinical efficacy of SNS can be prolonged in constipated patients, but in both the preliminary diagnostic assessment and pathophysiological interpretation every effort should be made to select patients for SNS. Although SNS showed efficacy in a low percentage of patients with STC, patients with OD were more responsive.

Sacral nerve stimulation for faecal incontinence and constipation: a European consensus statement

AIM

In Europe during the last decade sacral nerve stimulation (SNS) or sacral neuromodulation (SNM) has been used to treat faecal incontinence (FI) and constipation. Despite this, there is little consensus on baseline investigations, patient selection and operative technique. A modified Delphi process was conducted to seek consensus on the current practice of SNS/SNM for FI and constipation.

METHOD

A systematic literature search of SNS for FI and constipation was conducted using PubMed. A set of questions derived from the search and expert opinion were answered on-line on two occasions by an international panel of specialists from Europe. A 1-day face-to-face meeting of the experts finalized the discussion.

RESULTS

Three hundred and ninety-three articles were identified from the literature search, of which 147 fulfilled the inclusion criteria. Twenty-two specialists in FI and constipation from Europe participated. Agreement was achieved on 43 (86%) of 50 domains including the set-up of service, patient selection, baseline investigations, operative technique and programming of the device. The median of agreement was 95% (35-100%).

CONCLUSION

Consensus was achieved on the majority of domains of SNS/SNM for FI and constipation. This should serve as a benchmark for safe and quality practice of SNS/SNM in Europe.

Electrical Stimulation and Motor Recovery

In recent years, several investigators have successfully regenerated axons in animal spinal cords without locomotor recovery. One explanation is that the animals were not trained to use the regenerated connections. Intensive locomotor training improves walking recovery after spinal cord injury (SCI) in people, and >90% of people with incomplete SCI recover walking with training. Although the optimal timing, duration, intensity, and type of locomotor training are still controversial, many investigators have reported beneficial effects of training on locomotor function. The mechanisms by which training improves recovery are not clear, but an attractive theory is available. In 1949, Donald Hebb proposed a famous rule that has been paraphrased as “neurons that fire together, wire together.” This rule provided a theoretical basis for a widely accepted theory that homosynaptic and heterosynaptic activity facilitate synaptic formation and consolidation. In addition, the lumbar spinal cord has a locomotor center, called the central pattern generator (CPG), which can be activated nonspecifically with electrical stimulation or neurotransmitters to produce walking. The CPG is an obvious target to reconnect after SCI. Stimulating motor cortex, spinal cord, or peripheral nerves can modulate lumbar spinal cord excitability. Motor cortex stimulation causes long-term changes in spinal reflexes and synapses, increases sprouting of the corticospinal tract, and restores skilled forelimb function in rats. Long used to treat chronic pain, motor cortex stimuli modify lumbar spinal network excitability and improve lower extremity motor scores in humans. Similarly, epidural spinal cord stimulation has long been used to treat pain and spasticity. Subthreshold epidural stimulation reduces the threshold for locomotor activity. In 2011, Harkema et al. reported lumbosacral epidural stimulation restores motor control in chronic motor complete patients. Peripheral nerve or functional electrical stimulation (FES) has long been used to activate sacral nerves to treat bladder and pelvic dysfunction and to augment motor function. In theory, FES should facilitate synaptic formation and motor recovery after regenerative therapies. Upcoming clinical trials provide unique opportunities to test the theory.

A systematic review of sacral nerve stimulation mechanisms in the treatment of fecal incontinence and constipation

BACKGROUND

Sacral nerve stimulation (SNS) is now well established as a treatment for fecal incontinence (FI) resistant to conservative measures and may also have utility in the management of chronic constipation; however, mechanism of action is not fully understood. End organ effects of SNS have been studied in both clinical and experimental settings, but interpretation is difficult due to the multitude of techniques used and heterogeneity of reported findings. The aim of this study was to systematically review available evidence on the mechanisms of SNS in the treatment of FI and constipation.

METHODS

Two systematic reviews of the literature (performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses framework) were performed to identify manuscripts pertaining to (a) clinical and (b) physiological effects of SNS during the management of hindgut dysfunction.

KEY RESULTS

The clinical literature search revealed 161 articles, of which 53 were deemed suitable for analysis. The experimental literature search revealed 43 articles, of which nine were deemed suitable for analysis. These studies reported results of investigative techniques examining changes in cortical, gastrointestinal, colonic, rectal, and anal function.

CONCLUSIONS & INFERENCES

The initial hypothesis that the mechanism of SNS was primarily peripheral motor neurostimulation is not supported by the majority of recent studies. Due to the large body of evidence demonstrating effects outside of the anorectum, it appears likely that the influence of SNS on anorectal function occurs at a pelvic afferent or central level.

Sacral neuromodulation and peripheral nerve stimulation in patients with anal incontinence: an overview of techniques, complications and troubleshooting

Sacral neuromodulation (SNM) therapy has revolutionized the management of many forms of anal incontinence, with an expanded use and a medium-term efficacy of 75% overall. This review discusses the technique of SNM therapy, along with its complications and troubleshooting and a discussion of the early data pertaining to peripheral posterior tibial nerve stimulation in incontinent patients. Future work needs to define the predictive factors for neurostimulatory success, along with the likely mechanisms of action of their therapeutic action.

The SECCA procedure for faecal incontinence: a review

AIM

The SECCA system is a treatment option for patients with faecal incontinence and was introduced into clinical practice in 2002. Clinical studies of radiofrequency energy to treat patients with faecal incontinence have been published. This article aimed to review all published series to assess the results of this treatment.

METHOD

Twelve studies were included. Outcomes analysed included quality of life, the Wexner incontinence score, anorectal manometry and endoanal ultrasound findings.

RESULTS

A total of 220 patients from 10 studies were included. In the majority of clinical studies, the SECCA procedure has been shown to be an effective treatment of mild-to-moderate faecal incontinence.

CONCLUSION

When patient selection is appropriate, this treatment has demonstrated clinically significant improvements in symptoms, as demonstrated by statistically significant reductions in the Wexner incontinence and quality of life scores.

Systematic review of the clinical effectiveness of neuromodulation in the treatment of faecal incontinence

BACKGROUND

Over the past 18 years neuromodulation therapies have gained support as treatments for faecal incontinence (FI); sacral nerve stimulation (SNS) is the most established of these. A systematic review was performed of current evidence regarding the clinical effectiveness of neuromodulation treatments for FI.

METHODS

The review adhered to the PRISMA framework. A comprehensive search of the literature included PubMed, MEDLINE, Embase and Evidence-Based Medicine Reviews. Methodological quality assessment and data extraction were completed in a systematic fashion.

RESULTS

For SNS, 321 citations were identified initially, of which 61 studies were eligible for inclusion. Of studies on other neuromodulation techniques, 11 were eligible for review: seven on percutaneous tibial nerve stimulation (PTNS) and four on transcutaneous tibial nerve stimulation (TTNS). On intention-to-treat, the median (range) success rates for SNS were 63 (33-66), 58 (52-81) and 54 (50-58) per cent in the short, medium and long terms respectively. The success rate for PTNS was 59 per cent at the longest reported follow-up of 12 months. SNS, PTNS and TTNS techniques also resulted in improvements in Cleveland Clinic Incontinence Score and quality-of-life measures. Despite significant use of neuromodulation in treatment of FI, there is still no consensus on outcome reporting in terms of measures used, aetiologies assessed, length of follow-up or assessment standards.

CONCLUSION

Emerging data for SNS suggest maintenance of its initial therapeutic effect into the long term. The clinical effectiveness of PTNS is comparable to that of SNS at 12 months, although there is no evidence to support its continued effectiveness after this period. PTNS may be a useful treatment before SNS. The clinical effectiveness of TTNS is still uncertain owing to the paucity of available evidence. A consensus to standardize the use of outcome measures is recommended in order that further reports can be compared meaningfully.

Outcome of sacral nerve stimulation for fecal incontinence in patients refractory to percutaneous tibial nerve stimulation

BACKGROUND

Percutaneous tibial nerve stimulation and sacral nerve stimulation are both second-line treatments for fecal incontinence, but the comparative efficacy of the 2 therapies is unknown. In our institution, patients with refractory fecal incontinence are generally treated with percutaneous tibial nerve stimulation before being considered for sacral nerve stimulation.

OBJECTIVE

The aim of this study was to assess the outcome associated with this treatment algorithm in order to guide future management strategies.

DESIGN

All patients with fecal incontinence treated over a 3-year period with tibial nerve stimulation before receiving sacral nerve stimulation were identified from a prospectively recorded database. Demographics and pretreatment anorectal physiological data were available for all patients.

SETTINGS

This study was conducted at an academic colorectal unit in a tertiary center.

PATIENTS

Twenty patients (17 female:3 male, median age 55 (33-79) years) were identified to be refractory to percutaneous tibial nerve stimulation.

MAIN OUTCOME MEASURES

Clinical outcome data were collected prospectively before and after treatment, including 1) Cleveland Clinic Florida-Fecal Incontinence scores and 2) number of incontinence episodes per week.

RESULTS

The mean (±SD) pretreatment incontinence score (11.7 ± 3.5) did not differ from the mean incontinence score after 12 sessions of tibial nerve stimulation (10.9 ± 3.6, p = 0.42). All patients were subsequently counseled for sacral nerve stimulation, and 68.4% of them reported a significant therapeutic benefit with an improved incontinence score (7.7 ± 4.1, p = 0.014).

LIMITATIONS

This was a nonrandomized study with a relatively small number of patients

CONCLUSION

Sacral nerve stimulation appears to be an effective treatment for patients who do not gain an adequate therapeutic benefit from percutaneous tibial nerve stimulation and, thus, should be routinely considered for this patient cohort.

Sacral neuromodulation for bowel dysfunction: a consensus statement from the Italian group

BACKGROUND

Representatives from the Italian centers experienced in sacral neuromodulation (SNM) for the treatment of bowel dysfunction met in order to define the current clinical practice in Italy and to produce a consensus statement regarding indications for this therapy and patient management.

METHODS

Fifty Italian colonproctologists were asked to complete a questionnaire concerning their clinical practice in SNM (290 questions, grouped within 4 broad areas). Physicians expressed their opinion by completing the questionnaire, assigning to each statement their level of agreement according to the 5-point Likert scale; the data were analyzed by attributing to each expert's answers a weight proportional to the degree of experience. During a meeting held 2 months later, the critical aspects of the therapy were re-examined and discussions held with the goal of reaching an agreement on controversial topics. The available literature was reviewed.

RESULTS

Patient selection criteria, etiology, diagnostic investigations, test procedures and implantation, follow-up and evaluation of results have been reviewed. The aim was to achieve an algorithm for patient management, showing the place of SNM in the treatment of bowel dysfunction. The approach in case of treatment failure was also discussed.

CONCLUSIONS

Analysis of the data collected reveals substantial consensus at the national level concerning all the main points with regard to the therapy. The recommendations expressed in this article can be considered as national guidelines and taken into account by the principal international implantation centers.

The effect of sacral nerve stimulation on distal colonic motility in patients with faecal incontinence

BACKGROUND

Sacral nerve stimulation (SNS) is an effective treatment for neurogenic faecal incontinence (FI). However, the clinical improvement that patients experience cannot be explained adequately by changes in anorectal function. The aim of this study was to examine the effect of SNS on colonic propagating sequences (PSs) in patients with FI in whom urgency and incontinence was the predominant symptom.

METHODS

In patients with FI a high-resolution fibre-optic manometry catheter, containing 90 sensors spaced at 1-cm intervals, was positioned colonoscopically and clipped to the caecum. A unipolar or quadripolar tined electrode was implanted into the S3 sacral nerve foramen. Colonic manometry was evaluated in a double-blind randomized crossover trial, using true suprasensory stimulation or sham stimulation. Each stimulation period, lasting 2 h, was preceded by a 2-h basal manometric recording.

RESULTS

All 11 patients studied showed a colonic response to SNS. In ten patients there was a significant increase in the frequency of retrograde PSs throughout the colon during true stimulation compared with sham stimulation (P = 0·014). In one outlier, with baseline retrograde PS frequency nine times that of the nearest patient, a reduction in retrograde PS frequency was recorded. Compared with sham stimulation, SNS had no effect on the frequency of antegrade PSs or high-amplitude PSs.

CONCLUSION

SNS modulates colonic motility in patients with faecal urge incontinence. These data suggest that SNS may improve continence and urgency through alteration of colonic motility, particularly by increasing retrograde PSs in the left colon.

Neuromodulation for fecal and urinary incontinence: functional results in 57 consecutive patients from a single institution

BACKGROUND

Sacral nerve stimulation is a recognized treatment for fecal and urinary incontinence. Few articles have been published about patients presenting with both types of incontinence.

OBJECTIVE

The aim of this study was to report the functional results in patients operated on for simultaneous fecal and urinary incontinence by the use of sacral nerve stimulation.

DESIGN

This study is a retrospective analysis of prospectively collected data.

SETTINGS

The investigation was conducted in the academic departments of colorectal surgery and urology.

PATIENTS

Between January 2001 and March 2010, 57 consecutive patients (54 women) with a mean age of 58 years (range, 16-76) were included.

INTERVENTIONS

Two-stage sacral nerve modulation (test and implant) was performed.

MAIN OUTCOME MEASURES

Functional study before testing, at 6 months, and at the end of follow-up after implantation included the use of the Cleveland Clinic incontinence score, Urinary Symptoms Profile, Fecal Incontinence Quality of Life score, and the Ditrovie score. Patient satisfaction with the technique was evaluated at a median follow-up of 62.8 months.

RESULTS

: Fecal incontinence improved from 14.1/20 to 7.2/20 at 6 months and 6.9/20 at the end of follow-up. Urinary incontinence, mainly urge incontinence (47% of patients), and urgency frequency (34% of patients) improved at 6 months and end of follow-up, but not retention and dysuria. Specific quality of life was improved for fecal and urinary incontinence at 6 months and end of follow-up. At the end of follow-up, 73% patients were highly satisfied with the technique, but 9% felt their condition had deteriorated. The reoperation rate was 29%, of which 12% were indicated because of a complication.

LIMITATIONS

This study was limited by its retrospective nature and the multiple causes of incontinence.

CONCLUSION

Fecal and urinary incontinence, studied by symptoms scores and specific quality-of-life scores, are improved in patients receiving sacral nerve stimulation for double incontinence.

Turning off sacral nerve stimulation does not affect gastric and small intestinal motility in patients treated for faecal incontinence

AIM

Sacral nerve stimulation (SNS) reduces symptoms in up to 80% of patients with faecal incontinence (FI). Its effects are not limited to the distal colon and the pelvic floor. Accordingly, spinal or supraspinal neuromodulation have been suggested as part of the mode of action. The effect of SNS on gastric and small-intestinal motility was studied.

METHOD

Using the magnet tracking system, MTS-1, a small magnetic pill was tracked twice through the upper gastrointestinal tract of eight patients with FI successfully treated with SNS. Following a randomized double-blind crossover design, the stimulator was either left active or was turned off for 1 week before investigations with MTS-1.

RESULTS

The median (range) frequency of gastric con-tractions was 3.05 (2.83-3.40) per min during SNS and 3.04 (2.79?-3.76) per min without (P=NS). The median (range) frequency of contractions in the small intestine during the first 2h after pyloric passage was 10.005 (9.68-10.70) per min during SNS and 10.09 (9.79-10.29) per min without SNS (P=NS). The median (range) velocity of the magnetic pill during the first 2h in the small intestine was 1.6 (1.2-2.8) cm/min during SNS and 1.7 (0.8-3.7) cm/min without SNS (P=NS). Small-intestinal propagation mainly occurred during very fast movements (>15cm/min), accounting for 51% (42-60%) of the distance 3% (2-4%) of the time during SNS and for 53% (18-73%) of the distance 3% (1-8%) of the time without SNS (P=NS).

CONCLUSION

Turning off SNS for 1week did not affect gastric or small-intestinal motility patterns.

Sacral nerve stimulation in faecal incontinence associated with an anal sphincter lesion: a systematic review

AIM

The long-term results of sphincteroplasty for faecal incontinence due to an anal sphincter lesion have been disappointing. Initially sacral nerve stimulation was used only in faecal incontinence of neurogenic origin but subsequently the indications have been extended to other conditions. The aim of this review was to evaluate sacral nerve stimulation for incontinence in the presence of a sphincter defect.

METHOD

The MEDLINE, Embase and Cochrane Library databases for the period between 1995 and 2011 were searched for studies in English, with no limitations concerning the study size or the length of follow-up. The major endpoints were clinical efficacy, changes in anorectal manometry and quality of life.

RESULTS

Ten reports (119 patients) satisfied the inclusion criteria. The quality of the studies was low (nine were retrospective, one was prospective). All reported a lesion of the external anal and/or internal anal sphincter on endoanal ultrasound. A definitive implant was performed on 106 (89%) of the 119 patients who underwent a peripheral nerve evaluation test. The weighted average number of incontinent episodes per week decreased from 12.1 to 2.3, the weighted average Cleveland Clinic Score decreased from 16.5 to 3.8, and the ability to defer defaecation, when evaluated, increased significantly. The features at anorectal manometry did not change. The quality of life improved significantly in almost all studies.

CONCLUSION

Sacral nerve stimulation could be a therapeutic option for faecal incontinence in patients with an anal sphincter lesion. However, the quality of the published studies is low. A randomized clinical trial comparing sacral nerve stimulation with other classical surgical procedures at long-term follow-up, although beset with difficulties, should be conducted.

Electrical stimulation of the dorsal clitoral nerve reduces incontinence episodes in idiopathic faecal incontinent patients: a pilot study

AIM

Faecal incontinence (FI) has a significant impact on quality of life. This study investigates whether stimulation of the dorsal genital nerve (DGN) improves FI symptoms.

METHOD

Ten female patients suffering from idiopathic FI (median age 60 years) were included in the study. Stimulation was applied twice daily for 3 weeks at the maximal tolerable stimulation amplitude (pulse width, 200 μs; pulse rate, 20 Hz). Patients kept a 3-week bowel diary prior to stimulation, during stimulation and after the final stimulation. FI severity scores, FI Severity Visual-Analogue Score (VAS), FI Quality of Life Score (FIQL), sphincter function and rectal volume tolerance were assessed at baseline, immediately after stimulation and 3 weeks after stimulation.

RESULTS

Nine patients completed the study. The Wexner score (P=0.027) and the St Mark's score (P=0.035) improved after stimulation in seven and six of the patients and improvement was maintained 3 weeks after stimulation (P=0.048 and P=0.049, respectively). The number of incontinent episodes was reduced in seven out of nine patients (P=0.025). Improvement was maintained for 3 weeks after stimulation (P=0.017). Subjective assessments of FI severity using the VAS score and the FIQl score did not improve during stimulation. Sphincter function and rectal volume tolerability were unaffected.

CONCLUSION

DGN stimulation reduced the number of FI episodes in most patients suffering from idiopathic FI. Sphincter function and rectal volume tolerability were not affected. DGN stimulation may represent a new treatment for idiopathic FI.

Can sacral neuromodulation improve minor incontinence symptoms in doubly incontinent patients successfully treated for major incontinence symptoms?

OBJECTIVE

To describe the effect of sacral nerve modulation (SNM) on less severe types of incontinence in patients who were successfully implanted for either urinary or fecal incontinence, and who presented with double incontinence. When conservative treatments fail, SNM is a first-line treatment for patients with urge urinary or fecal incontinence.

METHODS

All patients who received SNM between 2005 and 2010 at 5 hospitals and who still had the implant were included in our survey. All received a urinary and fecal change and quality of life questionnaire by mail to complete.

RESULTS

Of the 51 questionnaires sent out, 37 were returned, for a 72.5% response rate. The population was composed of 97.3% women, with a mean age of 56.8 years (SD 14). The main indication for SNM was urge urinary incontinence in 15 patients (40.5%) and fecal incontinence in 22 patients (59.5%). Eighteen patients (48.7%) had improvements in both urinary and fecal incontinence symptoms. The percentage increased to 53.3% (16/30) in the group of patients with urge urinary incontinence associated with fecal incontinence. Patients who reported an improvement in double incontinence symptoms complained more often of urge urinary incontinence than other patients (P=.04).

CONCLUSIONS

Of the doubly incontinent patients who were successfully implanted for a predominant type of incontinence (ie, urinary or fecal incontinence), 48.7% had an improvement in the other type of incontinence. Patients with urge urinary incontinence associated with fecal incontinence were more likely to report an improvement in double incontinence than the other patients.

Postoperative issues of sacral nerve stimulation for fecal incontinence and constipation: a systematic literature review and treatment guideline

BACKGROUND

There is a lack of knowledge on the incidence and management of suboptimal therapeutic effect and the complications associated with sacral nerve stimulation for fecal incontinence and constipation.

OBJECTIVE

This study aimed to review current literature on postoperative issues and to propose a treatment algorithm.

DATA SOURCE

PubMed, MEDLINE, and EMBASE were searched using the keywords "sacral nerve stimulation," "sacral neuromodulation," "fecal incontinence," and "constipation" for English-language articles published from January 1980 to August 2010. A further search was conducted on a wider literature using the keywords "complication," "adverse effect," "treatment failure," "equipment failure," "infection," "foreign-body migration," "reoperation," "pain," and "algorithm."

STUDY SELECTION

Four hundred sixty-one titles were identified, and after a title and abstract review, 135 were subjected to full article review; 89 were finally included in this review. Five articles were added by manual search and consensus.

RESULTS

Forty-eight studies were identified as cohort studies reporting on postoperative issues, including 1661 patients who underwent percutaneous nerve evaluation and 1600 patients who proceeded to sacral nerve stimulation therapy. Pooled data showed that the most common problem during percutaneous nerve evaluation was lead displacement (5.3%). The incidence of suboptimal outcome, pain, and infection after implantation was 12.1%, 13.0%, and 3.9%.

LIMITATIONS

There was significant underreporting of untoward events, because 60% of the studies did not report complications during percutaneous nerve evaluation, and suboptimal outcome after implantation was not disclosed in 44% of the studies.

CONCLUSIONS

The incidence of untoward events associated with sacral nerve stimulation appears to be low. However, there is a significant underreporting of the incidence. Using the information from the structured and systematic literature review, we formulated a clinically relevant guideline for reporting and managing postoperative issues. The guideline can provide a framework for clinical practice.

Efficacy of sacral nerve stimulation for the treatment of fecal incontinence

BACKGROUND

Sacral nerve stimulation has been shown to be an effective treatment for fecal incontinence and early studies reported success rates of 67% to 100%. However, "success" has been arbitrarily set at a 50% reduction in symptoms, and data are rarely reported with "intention to treat."

OBJECTIVE

This study aimed to assess the true efficacy of sacral nerve stimulation for fecal incontinence compared with the published literature.

DESIGN

This prospective 5-year study was conducted to assess 50 patients with fecal incontinence treated with sacral nerve stimulation. All analyses were performed on an intention-to-treat basis.

SETTINGS

This study took place in a single tertiary referral colorectal department.

PATIENTS

Fifty consecutive patients with fecal incontinence refractory to conservative management were included in the study.

INTERVENTIONS

The interventions performed were temporary evaluation with or without permanent sacral nerve stimulation.

MAIN OUTCOME MEASURES

: Primary outcome measures were 1) attainment of continence, 2) reduction in fecal incontinence episodes, 3) improvement in Cleveland Clinic Fecal Incontinence scores, and 4) improvement in the ability to defer defecation.

RESULTS

Thirteen patients (26%) did not respond at the temporary evaluation stage or were dissatisfied with the result. Ten further patients (20%) did not achieve a 50% reduction in symptoms following permanent implantation. The median follow-up was 17 months (range, 2-55), at which time 27 patients (54%) experienced a 50% or more reduction in symptoms, including 13 (26%) who achieved apparent continence. Median fecal incontinence episodes per fortnight reduced from 14 (range, 0-53) to 2 (range, 0-20; P < .0001). Median Cleveland Clinic Fecal Incontinence scores reduced from 15 (range, 3-20) to 8 (range, 0-17; P < .0001). The ability to defer defecation improved significantly (P < .0001). These results compare favorably with the published literature.

LIMITATIONS

Quality of life was not assessed.

CONCLUSIONS

This study demonstrates that sacral nerve stimulation can be an effective treatment for patients with fecal incontinence; however, when analyzed by intention to treat, the symptoms of fecal incontinence continue in the majority (74%) of patients.

Sacral nerve stimulation for faecal incontinence: patient selection, service provision and operative technique

AIM

Faecal incontinence is estimated to affect between 2 and 3% of Western adult populations. In recent years sacral nerve stimulation has become an important treatment modality, often as the first-line surgical therapy. The aim of this article was to review the current evidence regarding patient selection and surgical technique and to evaluate the logistics of providing a neurostimulation service.

METHOD

A Medline search was performed including the keywords and/or MeSH headings of sacral nerve stimulation, neuromodulation, artificial pacemaker, faecal incontinence, patient selection, predictive factors and anal canal. Further studies were identified by cross-referencing from relevant articles and by appraisal of recent peer-reviewed conference abstracts and proceedings.

RESULTS

Despite the success of sacral nerve stimulation for several pathophysiological causes of incontinence, case selection is of paramount importance. Sacral nerve stimulation should not be offered outside a multidisciplinary pelvic floor unit. Temporary evaluation using diary cards can lead to false positive and negative results. Adherence to a meticulous surgical technique, using low amplitude stimulation to guide lead placement, provides optimal clinical outcome.

CONCLUSION

The short-term outcome of sacral nerve stimulation is dependent on patient factors and operative technique. Despite this, specific preoperative predictive factors of treatment success have yet to be identified.

Sacral nerve stimulation increases activation of the primary somatosensory cortex by anal canal stimulation in an experimental model

BACKGROUND

Sacral and posterior tibial nerve stimulation may be used to treat faecal incontinence; however, the mechanism of action is unknown. The aim of this study was to establish whether sensory activation of the cerebral cortex by anal canal stimulation was increased by peripheral neuromodulation.

METHODS

A multielectrode array was positioned over the right primary somatosensory cortex of anaesthetized rats. A brief burst of electrical stimulation was applied to either the left sacral root or the left posterior tibial nerve, and evoked potentials from anal canal stimulation were signal-averaged at intervals over 1 h. At the end of the experiment, the cerebral cortex was removed and probed for polysialylated neural cell adhesion molecule (PSA-NCAM).

RESULTS

Sacral nerve root and posterior tibial nerve stimulation significantly increased the peak amplitude of primary cortical evoked potentials by 54.0 and 45.1 per cent respectively. This change persisted throughout the period of observation. The density of PSA-NCAM-positive cells in the somatosensory cortex underlying the electrode array was increased by approximately 50 per cent in the sacral nerve-stimulated group.

CONCLUSION

Brief sacral neuromodulation induces profound changes in anal canal representation on the primary somatosensory cortex, providing a plausible hypothesis concerning the mechanism of action of neuromodulation in the treatment of faecal incontinence.

The role of sacral neuromodulation in double incontinence

AIM

Urinary and faecal incontinence are common conditions that are frequently associated. When conservative treatments fail, sacral nerve modulation (SNM) is considered to be a first-line treatment for patients with urge urinary incontinence and for patients with faecal incontinence. This article aims to determine the effect of SNM on the treatment of double incontinence (i.e. urinary and faecal incontinence).

METHOD

We searched for relevant articles in MEDLINE, PubMed and Embase, and for reviews in the Cochrane database. Articles were restricted to the English language.

RESULTS

Only a few studies have studied the efficacy of SNM for double incontinence and in a limited number of patients. Between 30% and 100% of patients with double incontinence experience improvement in urinary and faecal incontinence at medium-term follow up.

CONCLUSION

Further prospective trials are needed to determine which patients with combined problems will benefit from SNM at a long-term follow up.

Meta-analysis: sacral nerve stimulation versus conservative therapy in the treatment of faecal incontinence

AIM

Sacral nerve stimulation (SNS) has recently been used in the management of faecal incontinence (FI). This study compared SNS to conservative management with regards to functional and quality of life outcomes.

METHODS

Meta-analysis of studies published between 1995 and 2008 on SNS for FI was performed. Outcomes evaluated were functional, physiological and quality of life. A random-effects model was used and sensitivity analyses performed. Subgroup analyses were performed on age and sphincter status.

RESULTS

Thirty-four studies were included, reporting on 944 patients undergoing peripheral nerve evaluation; 665 underwent permanent SNS. Weekly incontinence episodes (weighted mean difference [WMD] -6.83; 95% confidence intervals [CI] -8.05, -5.60; p < 0.001) and incontinence scores (WMD -10.57; 95% CI -11.89, -9.24; p < 0.001) were significantly reduced with SNS; ability to defer defecation (WMD 7.99 min; 95% CI 5.93, 10.05; p < 0.001) was increased. Most SF-36 and FIQL domains improved following SNS, and mean anal pressures increased significantly (p < 0.001). Results remained consistent on sensitivity analysis. The under-56 years age group showed smaller functional but greater physiological and quality of life improvements. Results were similar between sphincter intact and impaired subgroups. The complication rate was 15% for permanent SNS, with 3% resulting in permanent explantation.

CONCLUSION

SNS results in significant improvements in objective and subjective measures for faecally incontinent patients.

Treatment of slow-transit constipation with sacral nerve modulation

AIM

Constipation is common and a selection of the best treatment is difficult, especially for slow-transit constipation (STC). The aim of the study was to assess the effect of sacral nerve modulation (SNM) on STC.

METHOD

A retrospective analysis of patients with STC, treated with SNM was undertaken. All were evaluated by cinedefecography, colon transit-time, Cleveland Clinic Constipation Score (CCS), SF-36 Quality of Life (QoL) and a bowel diary. Initially, all patients underwent a temporary implant for 4 weeks. The criteria of success were disappearance of necessity for laxatives or enema requirement, and improvement in QoL.

RESULTS

Fifteen patients with STC were treated from March 2003 to May 2006. Nine (60%) underwent permanent implantation. After SNM, the mean improvement of Wexner Constipation Score (CCS) and QoL was 10 and 6.2 respectively. There were no complications. The mean follow-up period was 42 months.

CONCLUSION

Sacral nerve modulation seems to be a useful option for STC.

Sacral nerve stimulation for the treatment of faecal incontinence related to dysfunction of the internal anal sphincter

PURPOSE

In patients with faecal incontinence related to isolated internal anal sphincter (IAS) disruption, conservative management is the mainstay of treatment. Surgical repair of the internal sphincter is not successful. This study evaluated the use of sacral nerve stimulation (SNS) in those with faecal incontinence and IAS disruption in whom medical and behavioural treatments had failed.

METHODS

Nine patients (seven women, median age 44 years, range 39-62 years), with a history of obstetric or iatrogenic anal sphincter trauma, underwent a trial of SNS. All had passive faecal incontinence, low resting anal sphincter pressure and full thickness IAS muscle disruption of greater than 30 degrees radial extent. The effect of SNS on symptoms was measured by a bowel habit diary and validated questionnaires used to assess impact on quality of life.

RESULTS

Eight (89%) patients benefited from temporary stimulation and proceeded to permanent device implantation. Follow-up was at a mean of 46 months (range 2-81). Faecal incontinence decreased from a mean (SD) of 9.9 (10.9) to 1.0 (2.4) episodes per week (p = 0.031), and soiling decreased from 6.1 (1.6) to 1.7 (2.4) episodes per week (p = 0.031), with chronic stimulation. At latest follow-up, three patients had no incontinence, three patients had episodes of minor soiling only, one patient had >75% reduction of incontinent episodes, and two patients remained incontinent.

CONCLUSIONS

Sacral nerve stimulation is effective in treating faecal incontinence related to a structurally and functionally abnormal internal anal sphincter. Treatment should not be refused on the basis of IAS disruption.

Six years of experience with sacral nerve stimulation for fecal incontinence

PURPOSE

Sacral nerve stimulation is one of many new surgical modalities for fecal incontinence. Short-term results from sacral nerve stimulation have been more encouraging than those from other modalities. The aim of this study was to report the outcome of percutaneous nerve evaluation tests and sacral nerve stimulation for the treatment of fecal incontinence from a single center covering a period of 6 years since the procedure was introduced.

METHODS

All of the candidates for a percutaneous nerve evaluation test and sacral nerve stimulation seen at our anal physiology unit between March 2001 and March 2007 were included in the study.

RESULTS

A total of 177 patients with fecal incontinence (160 females), median age 59.5 (range, 27-88) years, underwent a percutaneous nerve evaluation test. Of these patients, 142 (80%) had a positive test, including 21 of 25 (84%) patients who required a repeat percutaneous nerve evaluation test. Because of a functional failure, 16 patients underwent a revision of the permanent electrode, 7 of whom (44%) were satisfied with the functional result after the revision. Of 126 patients, 15 (12%) have undergone an explantation, with an infection rate of only 1.6%. Overall, after a median follow-up of 24 (range, 3-72) months, the median Wexner incontinence score decreased from 16 (range, 6-20) to 10 (range, 0-20) (P < .0001). In the 10 patients who underwent at least 6 years of treatment, the effect was sustained, as the median Wexner incontinence score decreased from 20 (range, 12-20) to 7 (range, 2-11) (P < .0001).

CONCLUSION

Sacral nerve stimulation is a simple, safe, and minimally invasive technique with low morbidity and excellent results, which appear to be maintained for the first 6 years after the procedure. For patients who underwent the treatment, median Wexner incontinence score decreased significantly after a median follow-up of 24 (range, 3-72) months. Twelve percent were explanted. The infection rate was 1.6%.

Sacral nerve stimulation is a valid approach in fecal incontinence due to sphincter lesions when compared to sphincter repair

PURPOSE

Anal sphincter lesions represent the major cause of fecal incontinence, particularly in women. Sphincteroplasty with overlap is the traditional treatment, but a significant reduction in benefits within 5 years of surgery has been reported. More recently, sacral nerve stimulation has been suggested following sphincteroplasty or as primary treatment.

METHODS

Overall, 24 women with fecal incontinence in the presence of anal sphincter lesions underwent sphincteroplasty (14 patients, mean age 47.6 +/- 15.6 years, range 26-70) or definitive implant of sacral nerve stimulation (10 patients, mean age 60.7 +/- 17.6 years, range 26-73), using identical selection criteria. At baseline, patients were studied with clinical evaluation, 3-dimensional endoanal ultrasound, and anorectal manometry (ARM), repeated at follow-up (median 60.0 months, range 6-96 in sphincteroplasty group; median 33.0 months, range 6-84 in sacral nerve stimulation group).

RESULTS

At baseline, both groups presented similar characteristics. Two sphincteroplasty patients (14.3%) experienced relapse of fecal incontinence at 6 and 19 months after treatment, whereas good to excellent continence was observed in all of the sacral nerve stimulation patients. Compared to baseline, both groups showed a significant improvement in clinical parameters, and ARM data remained unchanged. In 12 of 14 sphincteroplasty patients, the repaired sphincter at endoanal ultrasound was found to overlap. At follow-up, comparison between sphincteroplasty and sacral nerve stimulation showed no significant differences in clinical and ARM parameters, if related to lesion of internal, external, or both sphincters.

CONCLUSIONS

These data appear to confirm that sacral nerve stimulation could represent a valid alternative in the treatment of fecal incontinence patients presenting with sphincter lesion that was not preceded by sphincteroplasty.

Rectal motility after sacral nerve stimulation for faecal incontinence

Sacral nerve stimulation (SNS) is effective against faecal incontinence, but the mode of action is obscure. The aim of this study was to describe the effects of SNS on fasting and postprandial rectal motility. Sixteen patients, 14 women age 33-73 (mean 58), with faecal incontinence of various aetiologies were examined. Before and during SNS, rectal cross-sectional area (CSA) and ano-rectal pressures were determined with impedance planimetry and manometry for 1 h during fast and 1 h postprandially. Neither in the fasting state nor postprandially did SNS affect the number of single rectal contractions, total time with cyclic rectal contractions, the number of aborally and orally propagating contractions, the number of anal sampling reflexes or rectal wall tension during contractions. Postprandial changes in rectal tone were significantly reduced during SNS (P < 0.02). Before SNS, median rectal CSA was 2999 mm(2) (range: 1481-3822) during fast and 2697 mm(2) (range: 1227-3310) postprandially (P < 0.01). During SNS, median rectal CSA was 2990 mm(2) (1823-3678) during fast and 2547 mm(2) (1831-3468) postprandially (P = 0.22). SNS for faecal incontinence does not affect phasic rectal motility but it impairs postprandial changes in rectal tone.

Sacral neuromodulation for the treatment of fecal incontinence and urinary incontinence in female patients: long-term follow-up

PURPOSE

The purpose of this study was to evaluate improvement in symptoms of fecal incontinence (FI) in a group of women who also had urinary incontinence (UI) and were successfully implanted with the sacral neuromodulation (SNM) device primarily for urinary incontinence in one US institution.

METHODS

Twenty-four patients with FI and UI who failed to improve with conservative or standard surgical treatment underwent permanent SNM after a successful peripheral nerve stimulation test during 2003-2007. Wexner incontinence score, fecal incontinence quality of life (FIQL), and Bristol stool scales were recorded before and after treatment. Follow-up was done by questionnaires contact.

RESULTS

Twenty-four patients (mean age 56.5 +/- 5.3 years) were studied. The median follow-up was 28 months (range 3-49). Twenty-two patients (92%) were contacted. Seven patients (31.8%) experienced improvement in both urinary and fecal incontinence symptoms. Twelve patients (54.5%) experienced no improvement in FI symptoms after SNM. Four patients required a colostomy or ileostomy; four had the system explanted (two, due to a faded clinical response and two, due to infection); and four other patients experienced no improvement after SNM. The outcomes of ten patients (45.5%) with functioning SNM were reviewed. There were significant improvement of FI symptoms with a significantly lower Wexner score from 12.0 +/- 2.0 before SNM to 4.7 +/- 3.6 (p = 0.009). The mean FIQL scores improved significantly from the baseline score 7.8 +/- 0.8 before SNM to 13.5 +/- 2.6 (p = 0.009). Bristol stool form scale was reduced significantly from 4.5 to 3.5 after SNM (p = 0.02).

CONCLUSIONS

SNM may be beneficial in selected female patients with UI associated with FI. Prospective trials may help delineate which patients will show FI improvement in this combined group.

Factors associated with percutaneous nerve evaluation and permanent sacral nerve modulation outcome in patients with fecal incontinence

PURPOSE

Sacral nerve modulation is an established treatment for fecal incontinence. Little is known about predictive factors for successful percutaneous nerve evaluation (or test stimulation) and permanent sacral nerve modulation outcome. The purpose of this retrospective study was to discover predictive factors associated with temporary and permanent stimulation.

METHODS

We analyzed data from test stimulations performed in patients with fecal incontinence from March 2000 until May 2007. Successful outcome was defined as >50% improvement of incontinence episodes in three weeks. Patients with a successful test stimulation were eligible for permanent sacral nerve modulation implantation. All patients who subsequently had permanent sacral nerve modulation were analyzed. Logistic regression was used to determine the predictive power of baseline demographics and diagnostic variables.

RESULTS

Test stimulations were performed in 245 patients (226 females; mean age, 56.6 (standard deviation, 12.8) years). Our analysis showed that older age (P = 0.014), external anal sphincter defects (P = 0.005), and repeated procedures after initial failure (P = 0.001) were significantly related to failure. One hundred seventy-three patients (70.6%) were eligible for permanent sacral nerve modulation implantation. The analysis showed no significant predictive factors related to permanent sacral nerve modulation.

CONCLUSION

Three predictive factors were negatively associated with the outcome of test stimulation: older age, repeated procedures, and a defect in the external anal sphincter. These factors may indicate lower chances of success for test stimulation but do not exclude patients from sacral nerve modulation treatment. Although assessed in a selected patient group, no factors were predictive of the outcome of permanent stimulation.

Sacral nerve stimulation in faecal incontinence: position statement based on a collective experience

OBJECTIVE

Since the first paper published by Matzel et al., in 1995, on the efficacy of sacral nerve stimulation (SNS) in patients with faecal incontinence, the indications, the contraindications, the stimulation technique and follow up of implanted patients have changed. The aim of this article was to provide a consensus opinion on the management of patients with faecal incontinence treated with SNS.

METHOD

Recommendations were based on a critical review of the literature when available and on expert opinions in areas with insufficient evidence.

RESULTS

We have reviewed the indications and contraindications, proposed an algorithm for patient management showing the place of SNS. The temporary test technique, the implantation technique, the patient follow up and the approach in case of treatment failure were discussed.

CONCLUSION

We hope not only to provide a guide on patient management to clinical practitioners interested in SNS but also to harmonize our practices.

Sacral nerve stimulation and rectal function: results of a prospective study in faecal incontinence

The mechanisms of action of sacral nerve stimulation (SNS) to treat faecal incontinence remain poorly understood.

THE AIMS OF OUR STUDY WERE

(i) to measure the effect of SNS on rectal function and (ii) to evaluate rectal function as a predictive factor of clinical response to SNS. Rectal function was studied before and 3 months after permanent SNS in 18 patients (17 women, mean age 58.5 years) with faecal incontinence, using an electronic barostat. Rectal sensitivity and volume variations were recorded during isobaric distensions. Three months after SNS, 14 patients had a significant improvement of faecal incontience symptoms and four had not. Baseline 'maximal tolerated volume' was significantly lower in the positive response group (210 +/- 56 vs 286 +/- 30 mL, P = 0.02). Baseline rectal compliance was lower in patients with a positive response than those without, although this difference did not reach significance (6.2 +/- 3.2 vs 9.2 +/- 2.9 mL mmHg(-1),P = 0.10). Rectal compliance was not significantly modified by SNS. Our results suggest that an increased rectal capacity as measured by the maximal tolerated volume may be a predictive factor of poor response to SNS in faecal incontinence. SNS does not significantly modify rectal function.

Sacral nerve stimulation can improve continence in patients with Crohn's disease with internal and external anal sphincter disruption

PURPOSE

Sacral nerve stimulation is a technique commonly used for the treatment of idiopathic incontinence. This study was designed to assess the efficiency of sacral nerve stimulation as a means of treating fecal incontinence in patients with Crohn's disease with disrupted internal and external anal sphincters.

METHODS

Five patients (3 women) with fecal incontinence suffering from Crohn's disease-related anoperineal lesions were treated by applying three weeks of sacral nerve stimulation and then by permanent sacral nerve stimulation implantation. Endoanal ultrasonography showed that all of these patients had disrupted external and internal anal sphincters.

RESULTS

Continence was improved in all treated patients. The median follow-up time was 14 (range, 3-36) months. At the end of the follow-up period, the median Wexner's score significantly improved from 15 to 6 and the median number of daily stools decreased from 7 to 2. The patients' quality of life also increased significantly.

CONCLUSIONS

Sacral nerve stimulation improves fecal continence in patients suffering from Crohn's anoperineal lesions with internal and external anal sphincters disruption.

Sacral nerve stimulation in patients after rectal resection--preliminary report

INTRODUCTION

Sacral nerve stimulation is a widely accepted therapeutic option for neurogenic fecal incontinence. More recently, case reports showed a positive effect of sacral nerve stimulation in patients with fecal incontinence following low anterior resection. The purpose of this study was to gain more information for this selected indication for sacral nerve stimulation through a nationwide survey.

MATERIAL AND METHODS

In the period 2002 to 2005, three Austrian departments reported data of patients who underwent SNS for fecal incontinence following rectal resection. Data were available of seven patients (two female, five male) with a median age of 57 years (min 42; max 79). Six patients had undergone rectal resection as a treatment for low rectal cancer. One patient had undergone rectal resection for Crohn's disease, one patient subtotal colectomy and ileorectostomy for slow colon transit constipation.

RESULTS

Test stimulation was performed in the foramen S3 unilaterally over a median period of 14 days (2-21 days). Seven patients reported a marked reduction of episodes of incontinence during the observation period and received a permanent stimulation system. After a median follow-up of 32 months (17-46), five patients reported a marked improvement of their continence situation.

CONCLUSION

Despite a nationwide survey experiences with SNS as a treatment for fecal incontinence following rectal resection is still limited. Our observations show an improvement of the continence function following SNS. However, the promising results of our series as well as others need further research and more clinical data by a larger number of patients in a prospective trial.

A prospective, randomized study: switch off the sacral nerve stimulator during the night?

PURPOSE

Sacral nerve stimulation is an effective treatment for fecal incontinence. Some have recommended to "switch off" the pacemaker during the night to extend the lifetime of the expensive pacemaker. This study was designed to investigate whether a nightly "switch off" affects the clinical results of sacral nerve stimulation.

METHODS

Twenty patients successfully treated with sacral nerve stimulation (19 females; median age, 59 (range, 36-72) years) were randomized to: Group A, pacemaker continuously "on" for three weeks followed by three weeks with the pacemaker "off" during the night, or Group B, opposite order. Daily bowel-habit diary, Wexner, and St. Mark's incontinence scores were obtained.

RESULTS

One failed to return the daily bowel-habit diary, leaving 19 participating patients. Median Wexner incontinence score increased from 6 (range, 2-14) to 7 (range, 3-16) during the "off" period (P = 0.04), whereas St. Mark's incontinence score increased from 10 (range, 3-16) to 11 (range, 3-18; P = 0.03). Median number of days with soiling per three weeks increased from 0 (range, 0-12) to 1 (range, 0-15) during the "off" period (P = 0.008). Seven of 19 had more days with soiling during the "off" period. Defecation frequency per three weeks increased from 26 (range, 11-71) to 34 (range, 9-70) during the "off" period (P = 0.19). Only four continued with a nightly "switch off" after the study.

CONCLUSIONS

It could be considered to recommend compliant patients to "switch off" the pacemaker during the night to extend the lifetime of the pacemaker. One-third experienced increased soiling, and they should turn the pacemaker on all day and night. Among the remaining, only a minor proportion will be motivated for turning the pacemaker off.

Sacral nerve stimulation for faecal incontinence alters colorectal transport

Background

Sacral nerve stimulation reduces the frequency of defaecation in patients with faecal incontinence. The aim of this study was to examine the mechanism behind the reduced number of bowel movements in incontinent patients treated with sacral nerve stimulation.

Methods

The study included 20 patients with faecal incontinence and a positive percutaneous nerve evaluation test: 19 women and one man, with a median age of 63 (range 28–78) years. Colorectal scintigraphy was performed to assess colorectal emptying at defaecation before and after implantation. Segmental colorectal transit times were determined using radio-opaque markers.

Results

The median frequency of defaecation per 3 weeks decreased from 56 (range 19–136) to 26 (range 12–78) (P &lt; 0·002). At defaecation, antegrade transport from the ascending colon decreased from a median score of 8 (range 0–23) to 0 (range 0–11) per cent (P = 0·001), while retrograde transport from the descending colon increased from a median score of 0 (range 0–14) to 2 (range 0–30) per cent (P = 0·039). The median defaecation score was unchanged. There was a non-significant increase in median total gastrointestinal transit time from 2·5 (range 0·9–6·2) to 3·3 (range 0·8–6·2) days (P = 0·079).

Conclusion

Sacral nerve stimulation reduces antegrade transport from the ascending colon and increases retrograde transport from the descending colon at defaecation. This may prolong colonic transit time and increase the storage capacity of the colon.

Colonosphincteric electromyographic responses to sacral root stimulation: evidence for a somatosympathetic reflex

The aim of the present study was to determine the effects of selectively stimulating the afferent fibres running in the dorsal sacral roots (S1, S2, S3) and the somatic (radial and sciatic) nerves on colonic and internal anal sphincter (IAS) electromyographic (EMG) activity in anaesthetized cats to try to understand how sacral nerve stimulation can improve fecal continence in human. Electrically stimulating the afferent fibres present in the sacral dorsal roots and somatic nerves inhibited the colonic spike potential frequency (n = 97) and increased the slow variations in the sphincteric membrane potential (n = 76). These effects were found to have disappeared after administering an alpha-noradrenergic receptor blocker (n = 64) or sectioning the sympathetic efferent fibres innervating these organs (n = 69) suggesting the involvement of the sympathetic system in the effects observed. Moreover, no significant differences were observed between the effects of sacral dorsal root vs somatic nerve stimulation on colonic and sphincteric EMG activity. In conclusion, the data obtained here show that neurostimulation applied to the sacral spinal roots may improve fecal continence by inhibiting colonic activity and enhancing IAS activity via a somatosympathetic reflex.

Is a morphologically intact anal sphincter necessary for success with sacral nerve modulation in patients with faecal incontinence?

OBJECTIVE

Sacral nerve modulation (SNM) for the treatment of faecal incontinence was originally performed in patients with an intact anal sphincter or after repair of a sphincter defect. There is evidence that SNM can be performed in patients with faecal incontinence and an anal sphincter defect.

METHOD

Two groups of patients were analysed retrospectively to determine whether SNM is as effective in patients with faecal incontinence associated with an anal sphincter defect as in those with a morphologically intact anal sphincter following anal repair (AR). Patients in group A had had an AR resulting in an intact anal sphincter ring. Group B included patients with a sphincter defect which was not primarily repaired. Both groups underwent SNM. All patients had undergone a test stimulation percutaneous nerve evaluation (PNE) followed by a subchronic test over 3 weeks. If the PNE was successful, a permanent SNM electrode was implanted. Follow-up visits for the successfully permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter.

RESULTS

Group A consisted of 20 (19 women) patients. Eighteen (90%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. Group B consisted of 20 women. The size of the defect in the anal sphincter varied between 17% and 33% of the anal circumference. Fourteen (70%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. In both groups, the mean number of incontinence episodes decreased significantly with SNM (test vs baseline: P = 0.0001, P = 0.0002). There was no significant difference in resting and squeeze pressures during SNM in group A, but in group B squeeze pressure had increased significantly at 24 months. Comparison of patient characteristics and outcome between groups A and B revealed no statistical differences.

CONCLUSION

A morphologically intact anal sphincter is not a prerequisite for success in the treatment of faecal incontinence with SNM. An anal sphincter defect of <33% of the circumference can be effectively treated primarily with SNM without repair.

Normalization of substance P levels in rectal mucosa of patients with faecal incontinence treated successfully by sacral nerve stimulation

Background

Sacral nerve stimulation (SNS) may improve faecal incontinence by modulating rectal sensation. This study measured changes in the peripheral expression of various neural epitopes in response to SNS.

Methods

Rectal mucosal biopsies were taken from 12 patients before and after temporary SNS, and from ten responders at 90 days after permanent stimulation. Sections were immunostained for substance P, transient receptor potential vanilloid (TRPV) 1, vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP). Levels were compared with those in nine continent controls.

Results

Baseline levels of percentage area immunoreactivities of substance P (median 0·51 (95 per cent confidence interval 0·31 to 0·73) versus 0·13 (0·07 to 0·27) per cent; P &lt; 0·001) and TRPV1 (0·76 (0·41 to 1·11) versus 0·09 (0·04 to 0·14) per cent; P &lt; 0·001), but not of VIP (1·26 (0·37 to 2·15) versus 1·28 (0·39 to 2·17); P = 0·943), were significantly greater than in controls. Successful SNS resulted in a significant decrease in substance P immunostaining after temporary (0·15 (0·06 to 0·51) per cent; P = 0·051) and permanent (0·17 (0 to 0·46) per cent; P = 0·051) stimulation. Immunoreactivity of TRPV1, VIP, CGRP and neural markers showed no qualitative change.

Conclusion

Patients with faecal incontinence demonstrate normalization of raised rectal mucosal substance P levels following successful SNS.