Sacral nerve stimulation for treatment of fecal incontinence: a novel approach for intractable fecal incontinence

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 < 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.

Optimizing electrode implantation in sacral nerve stimulation--an anatomical cadaver study controlled by a laparoscopic camera

BACKGROUND AND AIM

Sacral nerve stimulation is the therapy of choice in patients with neurogenic faecal and urine incontinence, constipation and some pelvic pain syndromes. The aim of this study is to determine the best insertion angles of the electrode under laparoscopic visualization of the sacral nerves.

MATERIALS AND METHODS

Five fresh cadaver pelvises were dissected through an anterior approach of the presacral space, exposing the ventral sacral roots. Needles and electrodes were inserted into the S3 foramen. Both right and left sides were used, with the traditional percutaneous procedure. The validation was done by a laparoscopic camera controlling the position of the needle and electrode on the nerve. The angles were assessed with a goniometer and were confirmed in two living patients.

RESULTS

The mean angle of insertion in the sagittal plane was 62.9+/-3 degrees (range, 59-70). In the axial plane, the mean angle for the left side was 91.7+/-13.5 degrees (range, 80-110) and 83.2+/-7.7 degrees for the right side (range, 75-95). These angles resulted in the optimal placement of the leads along the S3 sacral root, in all these cases.

CONCLUSIONS

This study allows direct visualization during the placement of the needle and electrode, thus permitting accurate calculations of the best angle of approach during the surgical procedure in sacral nerve stimulation. These objective findings attempt to standardize this technique, which is often performed with the aid of intra-operative fluoroscopy but still leaving a lot to chance. These insertion angles should help to find more consistent and reproducible results and thus improved outcome in patients.

Effects and mechanisms of vaginal electrical stimulation on rectal tone and anal sphincter pressure

PURPOSE

This study was designed to evaluate the effect of vaginal electrical stimulation on rectal tone and compliance and anal sphincter pressure and to explore possible mechanisms involved in the effects of vaginal electrical stimulation on rectal tone in conscious dogs.

METHODS

Seven dogs inserted with a probe with two ring electrodes were studied. The study included two experiments. The first experiment was composed of two series of sessions rectal tone and compliance; and anal sphincter pressure. Each series included three sessions: vaginal electrical stimulation with long pulses, vaginal electrical stimulation with trains of long pulses, and vaginal electrical stimulation with trains of short pulses. The second experiment was performed in two sessions: vaginal electrical stimulation with long pulses plus guanethidine, and vaginal electrical stimulation with trains of long pulses plus guanethidine. In each session, rectal tone was recorded.

RESULTS

1) Vaginal electrical stimulation with long pulses or trains of long pulses but not trains of short pulses significantly decreased rectal tone and increased anal sphincter pressure. 2) None of the vaginal electrical stimulation methods altered rectal compliance. 3) The inhibitory effect of vaginal electrical stimulation on rectal tone was abolished by guanethidine.

CONCLUSIONS

Vaginal electrical stimulation with long pulses or trains of long pulses but not trains of short pulses reduces rectal tone and increases anal sphincter pressure. The inhibitory effect of vaginal electrical stimulation on rectal tone is mediated by the sympathetic pathway. These findings suggest that vaginal electrical stimulation may be a potential therapy for fecal incontinence.

Sacral neuromodulation in patients with faecal incontinence: results of the first 100 permanent implantations

OBJECTIVE

Faecal incontinence (FI) is a socially devastating problem. Sacral nerve modulation (SNM) has proven its place in the treatment of patients with FI. In this study, the first 100 definitive SNM implants in a single centre have been evaluated prospectively.

METHOD

Patients treated between March 2000 and May 2005 were included. Faecal incontinence was defined as at least one episode of involuntary faecal loss per week confirmed by a 3-week bowel habit diary. Patients were eligible for implantation of a permanent SNM when showing at least a 50% reduction in incontinence episodes or days during ambulatory test stimulation. Preoperative workup consisted of an X-defaecography, pudendal nerve terminal motor latency measurement, endo-anal ultrasound and anal manometry. The follow-up visits for the permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter. The bowel habit diary and anal manometry were repeated postoperatively during the follow-up visits.

RESULTS

A total of 134 patients were included and received a subchronic test stimulation. One hundred patients (74.6%) had a positive test stimulation and received a definitive SNM implantation. The permanent implantation group consisted of 89 women and 11 men. The mean age was 55 years (range 26-75). The mean follow-up was 25.5 months (range 2.5-63.2). The mean number of incontinence episodes decreased significantly during the test stimulation (baseline, 31.3; test, 4.4; P < 0.0001) and at follow-up (36 months postoperatively, 4.8; P < 0.0001). There was no significant change in the mean anal resting pressure. The squeeze pressures were significantly higher at 6 months (109.8 mmHg; P = 0.03), 12 months (114.1 mmHg; P = 0.02) and 24 months postoperatively (113.5 mmHg; P = 0.007). The first sensation, urge and maximum tolerable volume did not change significantly. Twenty-one patients were considered late failures and received further treatment.

CONCLUSION

Sacral neuromodulation is an effective treatment for FI. The medium-term results were satisfying.

Unilateral pudendal neuropathy is common in patients with fecal incontinence

PURPOSE

Pudendal neuropathy and fecal incontinence frequently coexist; however, the contribution of neuropathy is unknown. The pudendal nerve innervates the external anal sphincter muscle, anal canal skin, and coordinates reflex pathways. Lateral dominance or a dominantly innervating nerve and its subsequent damage may have major implications in the etiology and treatment of fecal incontinence. This study was designed to establish the prevalence of pudendal neuropathy, in particular a unilateral one, and to examine the impact on anorectal function.

METHODS

A total of 923 patients (745 females; mean age, 52 (range, 17-92) years) with fecal incontinence were studied using endoanal ultrasonography, anorectal manometry, rectal sensation, and pudendal nerve terminal motor latencies.

RESULTS

A total of 520 patients (56 percent) demonstrated a pudendal neuropathy, which was unilateral in 38 percent (351 patients; 169 right-sided, 182 left-sided). Neuropathy, whether it was bilateral (bilateral vs. normal; 56 (range, 7-154) cm H2O) vs. 67 (range, 5-215) cm H2O; P < 0.01) or unilateral (unilateral vs. normal; 61 (range, 0-271) cm H2O vs. 67 (range, 5-215) cm H2O; P = 0.04) was associated with reduced anal resting tone. This also was seen with respect to squeeze increments (bilateral vs. normal; 34 (range, 0-207) cm H2O vs. 52 (range, 0-378) cm H2O; P < 0.001, unilateral vs. normal; 41 (range, 0-214) cm H2O vs. 52 (range, 0-378) cm H2O; P < 0.01). In those with intact sphincters, unilateral neuropathy was associated with reduced squeeze increments (unilateral vs. normal; 60 (range, 10-286) cm H2O vs. 69 (range, 7-323) cm H2O; P = 0.01) but no significant reduction in resting pressures. There was no association between pudendal neuropathy and abnormal rectal sensitivity.

CONCLUSIONS

Unilateral pudendal neuropathy is a common abnormality in individuals with fecal incontinence and is significantly associated with both attenuated resting pressures and squeeze increments. Although there are limitations in the interpretation of pudendal nerve terminal motor latencies, this study demonstrates that further exploration of the concept of lateral dominance is needed.

Sacral nerve stimulation induces pan-colonic propagating pressure waves and increases defecation frequency in patients with slow-transit constipation

OBJECTIVE

Colonic propagating sequences are important for normal colonic transit and defecation. The frequency of these motor patterns is reduced in slow-transit constipation. Sacral nerve stimulation (SNS) is a useful treatment for fecal and urinary incontinence. A high proportion of these patients have also reported altered bowel function. The effects of SNS on colonic propagating sequences in constipation are unknown. Our aims were to evaluate the effect of SNS on colonic pressure patterns and evaluate its therapeutic potential in severe constipation.

METHOD

In eight patients with scintigraphically confirmed slow-transit constipation, a manometry catheter (16 recording sites at 7.5 cm intervals) was positioned colonoscopically and the tip fixed in the caecum. Temporary electrodes (Medtronic) were implanted in the S2 and S3 sacral nerve foramina under general anaesthesia. In the fasted state, 14 Hz stimulation was administered and four sets of parameters (pulse width 300 or 400 micros; S2 and S3) were tested in four 2-h epochs, in random order, over 2 days. Patients were then discharged home with the sacral wires in situ and a 3-week trial stimulation commenced during which patients completed a daily stool diary.

RESULTS

When compared with basal activity, electrical stimulation to S3 significantly increased pan-colonic antegrade propagating sequence (PS) frequency (5.4 +/- 4.2 vs 11.3 +/- 6.6 PS/h; P=0.01). Stimulation at S2 significantly increased retrograde PSs (basal 2.6 +/- 1.8 vs SNS 5.6 +/- 4.8 PS/h; P=0.03). During the subsequent three-week trial (continuous stimulation), six of eight reported increased bowel frequency with a reduction in laxative usage.

CONCLUSION

These data demonstrate that SNS induces pan-colonic propagating pressure waves and therefore shows promise as a potential therapy for severe refractory constipation.

Sacral nerve stimulation for fecal disorders: evolution, current status, and future directions

Sacral nerve stimulation (SNS) aims to recruit residual function of the anorectal continence organ by electrostimulation of its peripheral nerve supply. Since its first application for the treatment of fecal incontinence in 1994, its acceptance has been broadened and it is today considered a valuable addition to the therapeutic armentarium. Initially, its use was based on conceptual considerations, but changed to a pragmatic trial and error approach. Thus, the patients selection evolved: patients suffering from fecal incontinence due to a wide variety of causes are today selected for permanent SNS after a phase of temporary test stimulation. This test is highly predictive. If it is of clinical benefit, a neurostimulation device is implanted for chronic stimulation. Permanent stimulation not only improves or restores continence, but also has a substantial impact on quality of life. This has been uniformaly proven in multiple single and multicentre trials in a wide variety of aetiologies causing fecal incontinence. Despite the growing experience with the clinical use of SNS and its therapeutic effectiveness, the knowledge of its mechanism of action remains limited. Current research aims to improve our understanding of its action, to expand the spectrum of clinical applications and to implement recent technical developments.

Sacral neuromodulation in the treatment of defecation disorders

A large number of patients present with fecal incontinence due to idiopathic pelvic neuropathy or lesions of pelvic nerves, iatrogenic or secondary to other pelvic diseases or dysfunctions, involving sacral nerves. On the other hand, in many patients, constipation could be related to a peripheral neuropathy impairing normal defecation. Sacral neuromodulation (SNM) has been demonstrated as an effective approach in neuropathic defecation disorders. Its application is usually safe and easy, with a limited rate of complications or adverse events. The surgical procedure is made under local anesthesia. SNM effectiveness can be reliably tested during a short term period (up to 30 days) before the decision for a permanent implant. Results in most series show significant clinical improvement, with reduction in the number of incontinence episodes, decrease of incontinence score and improvement in patients' quality of life. A few reports suggest a potential and interesting application of SNM in constipation. Findings from anorectal manometry and other physiology examinations are not conclusive in order to define SNM mechanisms of actions and suggest that a multifactorial effect "modulates" the deficient neuromuscular system causing the defecation disorders.

Outcome and cost analysis of sacral nerve stimulation for faecal incontinence

BACKGROUND

Sacral nerve stimulation (SNS) may be successful in treating incapacitating faecal incontinence. The technique is expensive, and no cost analysis is currently available. The aim of this study was to assess clinical outcome and analyse cost-effectiveness.

METHODS

Thirty-six consecutive patients underwent a two-stage SNS procedure. Outcome parameters and real costs were assessed prospectively.

RESULTS

SNS was tested successfully in 33 of 36 patients, and 31 patients were stimulated permanently. In the first stage, eight of 36 patients reported minor complications (pain, infection or electrode dislocation), resulting in a cost of euro 4053 (range euro 2838-7273) per patient. For the second stage (permanent stimulation), eight of 33 patients had an infection, pain or loss of effectiveness, resulting in a cost of euro 11,292 (range euro 7406-20,274) per patient. Estimated costs for further follow-up were euro 997 per year. The 5-year cumulative cost for SNS was euro 22,150 per patient, compared with euro 33,996 for colostomy, euro 31,590 for dynamic graciloplasty and euro 3234 for conservative treatment.

CONCLUSION

SNS is a highly cost-effective treatment for faecal incontinence. Options for further reduction of SNS costs include strict patient selection, treatment in an outpatient setting and using cheaper devices.

Spinal nerve root stimulation

Spinal nerve root stimulation is a recently developed form of neuromodulation used for the treatment of chronic pain conditions. Unlike spinal cord stimulation, in which electrical impulses are directed at the dorsal columns, spinal nerve root stimulation guides electrical current directly to one or more nerve roots. There are a variety of techniques by which this can be accomplished, yet no consistent terminology to describe these variations exists. In this review, the authors group the various techniques according to anatomical approach, define each category, describe and illustrate each of the techniques, review the available reports on their uses, and discuss the advantages and disadvantages of each one.

Effects and mechanisms of anal electrical stimulation on anorectal compliance and tone in dogs

PURPOSE

This study was designed to investigate the changes in rectal compliance and tone during anal electric stimulation and the involvement of the alpha-adrenergic pathway in conscious dogs.

METHODS

Eight healthy dogs were studied in five randomized sessions. Anal sphincter pressure was quantified by using the area under the contractile curve. Rectal compliance and tone were measured in a pressure-controlled phasic and isobaric distention by using an electronic barostat. Anal electric stimulation was performed via a pair of ring electrodes attached to the catheter.

RESULTS

The electric stimulation-induced increase in sphincter pressure was lowered by the presence of an alpha(1)-adrenergic receptor antagonist, prazosin (18.6 +/- 7.4 vs. 45.4 +/- 9.7, P < 0.05), or alpha(2)-adrenergic receptor antagonist, yohimbine (10.2 +/- 8.2 vs. 38.3 +/- 7.6, P < 0.05), compared with the control. The threshold volume in rectoanal inhibitory reflex during electric stimulation was significantly higher than during baseline (27.5 +/- 0.9 vs. 22.5 +/- 1.9 ml, P < 0.05). There were no significant differences between the percentage drops in sphincter pressure with and without stimulation at a rectal distention level of 45 ml of air. Anal electric stimulation significantly increased rectal compliance reflected as reduced P(1/2) (11.1 +/- 1.5 vs. 16.7 +/- 1.1, P = 0.027) and reduced kappa (11.6 +/- 2.5 vs. 20.5 +/- 2.6, P = 0.0095), compared with the control session, but did not significantly alter rectal tone.

CONCLUSIONS

Anal electric stimulation increases anal sphincter pressure, mediated at least partially by the alpha-adrenergic pathway. It also increases rectal compliance but does not alter rectal anal inhibitory reflexes.

Rectal volume tolerability and anal pressures in patients with fecal incontinence treated with sacral nerve stimulation

PURPOSE

Sacral nerve stimulation has proven to be a promising treatment for fecal incontinence when conventional treatment modalities have failed. There have been several hypotheses concerning the mode of action of sacral nerve stimulation, but the mechanism is still unclear. This study was designed to evaluate the results of rectal volume tolerability, rectal pressure-volume curves, and anal pressures before and six months after permanent sacral nerve stimulation and to investigate the mode of action of sacral nerve stimulation.

METHODS

Twenty-nine patients with incontinence (male/female ratio = 6/23; median age, 58 (range, 29-79) years) underwent implantation of a permanent sacral electrode and neurostimulator after a positive percutaneous nerve evaluation test. Wexner incontinence score, rectal distention with thresholds for "first sensation," "desire to defecate," and "maximal tolerable volume," rectal pressure-volume curves, anal resting pressure, and maximum squeeze pressure were evaluated at baseline and at six months follow-up.

RESULTS

Median Wexner incontinence score decreased from 16 (range, 6-20) to 4 (range, 0-12; P < 0. 0001). Median "first sensation" increased from 43 (range, 16-230) ml to 62 (range, 4-186) ml (P = 0.1), median "desire to defecate" from 70 (range, 30-443) ml to 98 (range, 30-327) ml (P = 0.011), and median "maximal tolerable volume" from 130 (range, 68-667) ml to 166 (range, 74-578) ml (P = 0.031). Rectal pressure-volume curves showed a significant increase in rectal capacity (P < 0.0001). The anal resting pressure increased significantly from 31 (range, 0-109) cm H(2)O to 38 (range, 0-111) cm H(2)O (P = 0.045). No significant increase in maximum squeeze pressure was observed.

CONCLUSIONS

For patients with fecal incontinence successfully treated with sacral nerve stimulation, there was a significant increase in rectal volume tolerability and rectal capacity. A significant increase in anal resting pressure, but not in maximum squeeze pressure, was found. We suggest that sacral nerve stimulation causes neuromodulation at spinal level.

Sacral neuromodulation in the treatment of severe anal incontinence

INTRODUCTION

Sacral neuromodulation is a recognized therapeutic option in severe anal incontinence from neurogenic origins, when medical treatment has failed.

METHODS

We report the results of this procedure applied in 40 consecutive patients operated on by a single surgeon from August 2001 to June 2004. Mean duration of incontinence was 5 years. There were 33 women and 7 men of mean age 59 (range 29-89). All patients had had medical treatment, 26 had had physiotherapy and 9 had been previously operated on for that problem. Neuromodulation consisted in a temporary electrical stimulation test followed by implantation of a stimulator in case of efficacy.

RESULTS

Twenty nine patients had a positive test and were implanted. Ten had a negative test and one is waiting for implantation. From the 29 patients, 23 had uneventful postoperative course. Incontinence score varied from 17 before neuromodulation to 6 after in the 24 patients who were improved. Mean resting pressure, mean maximum squeeze pressure and mean duration of squeeze pressure did not change from pre to postoperative period.

CONCLUSION

Sacral neuromodulation is a safe and efficacious procedure in properly selected anal incontinent patients. However, we observed no correlation between clinical and manometric data.

Rectal hyposensitivity

Rectal hyposensitivity (RH) relates to a diminished perception of rectal distension that is diagnosed during anorectal physiologic investigation. There have been few direct studies of this physiologic abnormality, and its contribution to the development of functional bowel disorders has been relatively neglected. However, it appears to be common in patients with such disorders, being most prevalent in patients with functional constipation with or without fecal incontinence. Indeed, it may be important in the etiology of symptoms in certain patients, given that it is the only "apparent" identifiable abnormality on physiologic testing. Currently, it is usually diagnosed on the basis of elevated sensory threshold volumes during balloon distension in clinical practice, although such a diagnosis may be susceptible to misinterpretation in the presence of altered rectal wall properties, and thus it is uncertain whether a diagnosis of RH reflects true impairment of afferent nerve function. Furthermore, the etiology of RH is unclear, although there is limited evidence to support the role of pelvic nerve injury and abnormal toilet behavior. The optimum treatment of patients with RH is yet to be established. The majority are managed symptomatically, although "sensory-retraining biofeedback" appears to be the most effective treatment, at least in the short term, and is associated with objective improvement in the rectal sensory function. Currently, fundamental questions relating to the contribution of this physiologic abnormality to the development of functional bowel disorders remain unanswered. Acknowledgment of the potential importance of RH is thus required by clinicians and researchers to determine its relevance.

Sacral neuromodulation; does it affect colonic transit time in patients with faecal incontinence?

OBJECTIVE

Sacral neuromodulation (SNM) has been a successful treatment in urinary voiding disorders for years. A concomitant effect on bowel function was observed leading to the treatment of faecal incontinence with SNM. In this study we describe the effect of SNM on bowel frequency and (segmental) colonic transit time.

PATIENTS AND METHODS

Fourteen patients with faecal incontinence who qualified for permanent SNM underwent a colon transit study before and one month after permanent implant. Patients completed a three-week bowel habits diary before and during stimulation.

RESULTS

Median incontinence episodes and days per week before SNM were, 8.7 and 4.2, respectively, and both decreased significantly to 0.67 (P = 0001) and 0.5 (P = 0001) during trial screening and to 0.33 (P = 0001) and 0.33 (P = 0001) after permanent implant. The median number of bowel movements per week decreased from 14.7 (6.7-41.7) to 10.0 (3.7-22.7)(P = 0005) during trial screening and to 10.0 (6.0-24.3)(P = 0008) during permanent stimulation. Resting and squeeze pressures did not change significantly during stimulation. Segmental colonic transit time before and during stimulation for right colon, left colon and recto sigmoid were, respectively, 6 (0-25) vs 5 (0-16) hours, 2 (0-29) vs 4 (0-45) hours and 7 (28) vs 8 (0-23) hours. No significant changes were found in both segmental and total colonic transit time; 17 (1-65) vs 25 (0-67) hours.

CONCLUSION

SNM in patients with fecal incontinence led to a significant decrease of bowel movements however (segmental) colonic transit time was not influenced.

Anal electrical stimulation with long pulses increases anal sphincter pressure in conscious dogs

PURPOSE

This study was designed to investigate the effects and mechanisms of anal electric stimulation with long pulses on anal sphincter pressure in conscious dogs.

METHODS

The study was performed after enema in nine healthy female hound dogs and composed of four randomized sessions ("dose"-response, anal electric stimulation only, or with atropine or phentolamine). The anal sphincter pressure was measured by using manometry and quantified by using the area under the contractile curve (mmHg/sec). Anal electric stimulation was performed via a pair of ring electrodes attached to a manometric catheter. The stimulation parameters in all but dose-response sessions included a frequency of 20 ppm, pulse width of 200 ms, and amplitude of 3 mA.

RESULTS

The anal sphincter pressure was 55.7 +/- 6 at baseline and increased by 37 percent to 76.4 +/- 6.5 during electric stimulation (P = 0.009). The increase of anal pressure during stimulation was positively correlated with the stimulation energy (r = 0.395; P < 0.01). The excitatory effect of electric stimulation was sustained for at least 20 minutes. Atropine did not alter anal pressure and did not abolish the excitatory effect of anal electric stimulation on the sphincter. Phentolamine reduced anal pressure from the baseline value of 50.5 +/- 4.7 to 33.1 +/- 5.4 (P = 0.019). The electric stimulation induced increase in anal pressure was dropped from 19 +/- 2.6 to 9.9 +/- 2.8 (P = 0.029) at the presence of phentolamine.

CONCLUSIONS

Anal electric stimulation with long pulses increases anal sphincter pressure in an energy-dependent manner. The alpha-adrenergic but not the cholinergic pathway at least partially mediates the excitatory effect of anal electric stimulation.

Short-term effects of magnetic sacral dermatome stimulation for idiopathic slow transit constipation: sham-controlled, cross-over pilot study

BACKGROUND AND AIM

An increase in recto-sigmoid colon activity through electrical stimulation of the sacral dermatomes has previously been reported. It has not been evaluated whether or not sacral dermatome stimulation has beneficial effects on constipation symptoms and anorectal function in constipated patients. Our aim was to evaluate short-term effects of magnetic stimulation of the sacral dermatomes on constipation symptoms and anorectal function in patients with idiopathic slow transit constipation.

METHOD

Fourteen patients with idiopathic slow transit constipation were enrolled. Constipation symptoms, stool form and anorectal function were assessed before treatment, and at 3 and 6 weeks of treatment. Six-week treatment consisted of either a 3-week period of sham treatment or a 3-week period of magnetic stimulation of the S2-S3 dermatomes, which was performed in a randomized cross-over design.

RESULTS

During the stimulation period, the frequency score of spontaneous bowel movements decreased in eight of the 14 patients (2.9 [2-3]vs 1.4 [0-2]), whose threshold volumes for urge to defecate and maximum tolerable volumes were significantly greater than those of the non-responders, and significantly decreased at the end of treatment. The degree of straining on defecation also significantly decreased in the responders. Responders had shorter right colonic transit time and longer left colonic transit time compared to the non-responders. Sham treatment did not affect constipation symptoms, stool form and rectal sensation.

CONCLUSION

Sacral dermatome stimulation may offer potential for therapeutic benefit for a subset of patients with idiopathic slow transit constipation, particularly constipated patients with rectal hyposensation or hindgut dysfunction.

Sacral nerve stimulation for faecal incontinence following a rectosigmoid resection for colorectal cancer

INTRODUCTION

Following recto-sigmoid resection some patients may become faecally incontinent and remain so despite conservative treatment. This multicentre prospective study assessed the use of sacral nerve stimulation (SNS) in this group.

METHODS

All patients had more than or equal to 4 days of faecal incontinence for solid or liquid stools over a 21-day period following recto-sigmoid resection for colorectal carcinoma. The operation had to have been deemed curative. They had to have failed pharmacological and biofeedback treatment.

RESULTS

Three male patients met these criteria. One had had a colo-anal and two a colo-rectal anastomosis for rectal carcinoma. All patients had intact internal and external anal sphincters. Two patients had a successful temporary stimulation period and proceeded to permanent implantation. Pre-operative symptom duration was 1 year in the permanently implanted patients. They were followed up for 12 months. SNS improved the number of faecally incontinent episodes in both patients. Ability to defer was improved in both patients from 0--5 min to 5--15 min. The faecal incontinence-specific ASCRS quality of life assessment improved in all four subcategories.

CONCLUSION

This study demonstrates that SNS may be effective in the treatment of patients with faecal incontinence following recto-sigmoid resection if conservative treatment has failed.

Fecal incontinence: an up-to-date critical overview of surgical treatment options

BACKGROUND

Surgery is the last resort for patients suffering from severe fecal incontinence. The armamentarium of surgical options for this condition has increased impressively during the last decade. Nevertheless, this fact seems to make neither patients nor surgeons feel more comfortable. Treatment of fecal incontinence still remains a challenge to modern medicine due to many specific sides of this problem.

AIMS

This article gives an up-to-date overview of existing operative treatment options.

METHODS

An unbiased review of relevant literature was performed to assess the role of all methods of surgical treatment for fecal incontinence available nowadays.

RESULTS

Recent studies have shown poor late results after primary sphincter repair and low predictive value for most preoperative diagnostic tests. New surgical options such as artificial devices and electrically stimulated muscle transpositions are doomed by low success rates and unacceptably frequent complications. That is why current attention has focused on non- or minimally invasive therapies such as sacral nerve stimulation and temperature-controlled radio-frequency energy delivery to the anal canal. However, all these innovative techniques remain experimental till enough high-evidence data are gathered for their objective evaluation.

CONCLUSION

Careful and detailed preoperative assessment to exactly determine the etiology of incontinence and individual approach remain the cornerstones of surgical treatment of fecal incontinence nowadays.

Sacral nerve stimulation reduces corticoanal excitability in patients with faecal incontinence

Background

Sacral nerve stimulation (SNS) can produce symptomatic relief in patients with faecal incontinence. Moreover, peripheral nerve stimulation has been shown to affect brain function. The aim of this study was to determine whether SNS might produce important changes in cortical activity linked to improved continence.

Methods

In an experimental study, ten women with intractable faecal incontinence (mean age 51·3 years) were serially mapped with transcranial magnetic stimulation before and immediately after 14 days of temporary SNS (15 Hz, pulse width 210 µs), and then 2 weeks later. Anal sphincter electromyographic responses were recorded to cortical stimulation of multiple points over a scalp grid covering the bilateral medial cortex. Continence scores, anorectal manometry and rectal sensitivity data were also collected.

Results

SNS improved global symptom scores in the majority of patients; mean(s.e.m.) continence scores fell from 16·9(1·6) to 10·6(1·8) (P = 0·042). Cortical mapping showed a consistent decrease in corticoanal representation and overall excitability immediately after SNS compared with baseline (mean(s.e.m.) 38 083(13 669) versus 42 507(13 297) µV s; P = 0·017), which was reversed 2 weeks after SNS wire removal.

Conclusion

SNS produces symptom benefit in patients with faecal incontinence that is associated with a reversible reduction in corticoanal excitability. SNS therefore drives dynamic brain changes that may play a functional role in influencing anal continence.

Sacral nerve stimulation for faecal incontinence in patients with previous partial spinal injury including disc prolapse

BACKGROUND

This study examined the use of sacral nerve stimulation (SNS) to treat faecal incontinence in patients with partial spinal injury.

METHODS

Patients selected for SNS had experienced more than one episode of faecal incontinence per week to liquid or solid stool for more than 1 year and had failed maximal conservative treatment. All patients had an intact external anal sphincter.

RESULTS

Temporary SNS was performed in 13 patients (median age 58.5 (range 39-73) years). The spinal insults were disc prolapse (six), trauma (four), spinal stenosis (one) or occurred during neurosurgery (two). Twelve patients (eight women and four men) had successful temporary stimulation and proceeded to permanent implantation. The median follow-up time was 12 (range 6-24) months. The mean(s.d.) number of episodes of incontinence decreased from 9.33(7.64) per week at baseline to 2.39(3.69) at last follow-up (P = 0.012). The number of days per week with incontinence and staining decreased significantly (both P < 0.001). Ability to defer defaecation improved from a median of not being able to defer (range 0-1 min) to being able to defer for 5-15 (range 0 to over 15) min (P = 0.022).

CONCLUSION

SNS can benefit patients with faecal incontinence following partial spinal injury.

Effect of sacral neuromodulation on the rectum

Background

Sacral neuromodulation (SNM) is a new treatment for faecal incontinence. At present the exact underlying mechanism is still unclear. Modulation of the sacral reflex arcs might have an effect on rectal sensitivity, wall tension and compliance.

Methods

Fifteen consecutive patients with faecal incontinence who qualified for SNM underwent barostat measurements before and during neuromodulation. An ‘infinitely’ compliant plastic bag with a volume of 600 ml was placed in the rectum and connected to a computer-controlled barostat system. An isobaric phasic distension protocol was used. Patients were asked to report rectal filling sensations: first sensation (FS), earliest urge to defaecate (EUD) and an irresistible, painful urge to defaecate (maximum tolerated volume; MTV). Rectal wall tension and compliance were calculated.

Results

During isobaric phasic distension each patient experienced all rectal filling sensations at the time of stimulation. Median volume thresholds decreased significantly during stimulation, from 98·1 to 44·2 ml for FS (P = 0·003), from 132·3 to 82·8 ml for EUD (P = 0·001) and from 205·8 to 162·8 ml for MTV (P = 0·002). Pressure thresholds tended to be lower for all filling sensations, but only that to evoke MTV was reduced significantly by stimulation (37·3 versus 30·3 mmHg; P = 0·005). Median rectal wall tension for all filling sensations decreased significantly with stimulation. There was no significant difference between compliance before and during stimulation.

Conclusion

SNM affects rectal sensory perception, but further research is required to clarify the mechanism.

Sacral nerve stimulation for fecal incontinence following surgery for rectal prolapse repair: a multicenter study

PURPOSE

A proportion of patients have fecal incontinence secondary to a full-thickness rectal prolapse that fails to resolve following prolapse repair. This multicenter, prospective study assessed the use of sacral nerve stimulation for this indication.

METHODS

Patients had to have more than or equal to four days with fecal incontinence per 21-day period more than one year after surgery. They had to have failed conservative treatment and have an intact external anal sphincter.

RESULTS

Four female patients aged 42, 54, 68, and 65 years met the inclusion criteria. Three of the four patients had had more than one operation for recurrent full-thickness rectal prolapse before sacral nerve stimulation, one of whom had undergone a further operation for recurrence following stimulation. One patient had undergone one operation for prolapse repair. The preoperative duration of symptoms was ten, eight, three, and nine years, respectively. Although patients had an intact external anal sphincter, one patient had a fragmented internal anal sphincter. The frequency of fecal incontinent episodes changed from 11, 24.7, 5, and 8 per week at baseline to 0, 1.5, 5.5, and 1 per week at latest follow-up. Ability to defer defecation was also improved in two of three patients who had this documented. Fecal incontinence-specific quality of life assessment showed an improvement in all four domains.

CONCLUSION

Sacral nerve stimulation should be considered for patients with ongoing fecal incontinence following full-thickness rectal prolapse repair if they prove resistant to conservative treatment.

Sacral neuromodulation in treatment of fecal incontinence following anterior resection and chemoradiation for rectal cancer

PURPOSE

Fecal incontinence may occur in patients who have undergone anterior resection for rectal cancer without presenting sphincter lesions. Chemoradiation may contribute to disrupting continence mechanisms. Treatment is controversial. Assessment of fecal incontinence in patients who agreed to integrate treatment for rectal cancer and treatment with sacral neuromodulation are reported.

METHODS

Fecal incontinence following preoperative chemoradiation and anterior resection for rectal cancer was evaluated in four patients. A good response was observed during the percutaneous sacral nerve evaluation test, and so permanent implant of sacral neuromodulation system was performed. Reevaluation was performed at least two months after implant.

RESULTS

After device implantation, the mean fecal incontinence scores decreased, and the mean number of incontinence episodes dropped from 12.0 to 2.5 per week (P < 0.05). Permanent implant resulted in a significant improvement in fecal continence in three patients, and incontinence was slightly reduced in the fourth. Manometric parameters agreed with clinical results: maximum and mean resting tone and the squeeze pressure were normal in three patients and reduced in one. In these same three patients, neorectal sensation parameters increased when the preoperative value was normal or below normal and decreased when the preoperative value was higher than normal, whereas in one patient in whom extremely low values were recorded all of the parameters decreased significantly.

CONCLUSIONS

Fecal incontinence following anterior resection and neoadjuvant therapy should be carefully evaluated. If a suspected neurogenic pathogenesis is confirmed, sacral neuromodulation may be proposed. If the test results are positive, permanent implant is advisable. Failure of this approach does not exclude the use of other, more aggressive treatment.

Sacral nerve stimulation: an emerging treatment for faecal incontinence

Faecal incontinence is common, distressing to the patient and socially incapacitating. The treatment options depend on the severity and aetiology of incontinence. For mild cases of faecal incontinence, medical management and pelvic floor physiotherapy may be adequate. For more severe cases, surgery is often required. Patients who have a distinct sphincter defect are amenable to surgical repair. In many cases, there is a combination of diffuse structural damage of the anal sphincters with pudendal neuropathy. Conventional surgical repairs have a modest degree of success and the results tend to deteriorate with time. Neosphincter procedures such as artificial bowel sphincter and dynamic graciloplasty are potentially morbid and technically complex. Sacral nerve stimulation is innovative and has had a medium-term success with improvement of quality of life in over 80% of patients treated for faecal incontinence. These results are superior to other techniques in treating patients with severe refractory faecal incontinence, where current maximal therapy has failed. The technique is unique because there is a screening phase, which has a high predictive value. It is also associated with minimal complications that are usually minor. However, most published reports of sacral nerve stimulation for treatment of faecal incontinence were case studies and methods of assessing outcome were variable. Criteria for patient selection are evolving and are yet to be defined. The present paper critically reviews the publications to date on sacral nerve stimulation for treatment of faecal incontinence. This will form the basis for future evaluation of this emerging treatment of severe, intractable faecal incontinence. Randomized clinical trials like that of the Melbourne trial will further clarify the role and indications of sacral nerve stimulation for faecal incontinence.

A review of contemporary surgical alternatives to permanent colostomy

OBJECTIVES

To review the options available to patients with faecal incontinence with failed conservative treatment and/or failed anal sphincter repair and assessing the current indications and results of these options.

METHODS

A literature search of MEDLINE, EMBASE and Cochrane databases was performed using the relevant search terms.

RESULTS

Continent options for patients with severe or end stage faecal incontinence include the creation of a form of an anal neosphincter and more recently sacral nerve stimulation. Over half the patients, who are candidates, may benefit from these procedures, although long term results of sacral nerve stimulation are unknown. Dynamic graciloplasty improves the continence in 44-79% of the patients. The complications include frequent reoperations, high incidence of infection and obstructive defaecation. The success rates of artificial bowel sphincter vary between 24% and 79%. Once functional, the artificial bowel sphincter seems to improve the continence in the majority of the patients. Device removal due to infection, obstructive defaecation and pain is a frequent problem. Sacral nerve stimulation is claimed to result in improvement in continence in 35-100% of patients. The main risks in this procedure are infection, electrode displacement and pain.

CONCLUSIONS

All these procedures have high complication rates and have moderate success rates only. A major proportion of patients will need reoperations and hence high motivation is necessary for patients who undergo these procedures. A uniform standard for measurement of success is also necessary so that these procedures can be compared with each other.

Determination of therapeutic threshold in sacral nerve modulation for faecal incontinence

Background

The aim of the study was to determine the therapeutic stimulation threshold in patients with successful sacral nerve modulation for faecal incontinence.

Methods

Patients who had undergone successful permanent sacral nerve modulator implantation and had been followed up for a minimum of 3 months were included. The sensitivity threshold and motor threshold were determined and correlated with therapeutic response. Patients went home with the stimulator set at 0·6 V below the sensitivity threshold. Each week the voltage was increased by 0·2 V until the sensitivity threshold was reached. The effects on anorectal physiology and continence were recorded.

Results

Eight patients (seven women) with a median age of 58·5 years were included. The median follow-up was 6·3 months. The median sensibility threshold volume of rectal sensation was 50 ml, the median urge threshold volume was 140 ml and the median maximum tolerated rectal volume 240 ml. The median number of incontinence episodes and days per week affected by incontinence decreased from 5·0 and 3·8 before operation to 0·7 and 0·7 respectively after follow-up for 3 months. At anorectal manometry the median resting and stimulation anal canal pressures were 57 and 85 mmHg respectively, and remained constant over time. The therapeutic response threshold was significantly lower than the sensitivity threshold (median 1·6 versus 1·7 V; P = 0·042). The median motor threshold was 2·1 V, significantly higher than the sensitivity threshold (P = 0·009). The stimulation threshold for suboptimal therapeutic response was 1·4 V. In five of the eight patients the therapeutic response threshold was the same as the sensitivity threshold.

Conclusion

Sacral nerve modulation can produce a therapeutic effect below the sensitivity threshold. A lower stimulation voltage increases the lifespan of the pulse generator.

Innovations in fecal incontinence: sacral nerve stimulation

OBJECTIVE

The aim of this study was to present an overview of sacral nerve stimulation in the treatment of fecal incontinence. We describe the evolution in technique, patient selection, and indications, and review results and complications.

METHODS

All articles on sacral nerve stimulation for fecal incontinence that were recovered on MEDLINE search were reviewed. With multiple articles from an institution, the most recent reports with the longest follow-up and largest cohort of patients were selected, unless information from earlier reports was relevant.

RESULTS

The technique of sacral stimulation is well established, carries little risk, and continues to be refined (e.g., a less invasive approach has been proposed). Patient selection is based on a two-stage diagnostic test stimulation (acute and subchronic), for which the predictive value is high. On this basis, permanent sacral nerve stimulation has proved effective in both single-center and multicenter trials in patients with a functional deficit but limited morphologic lesions or no morphologic lesions. The clinical benefit derives from multiple symptomatic improvements contributing to better bowel control and from substantially improved quality of life. The underlying mechanism of action remains undefined, but both somatic and autonomic function appears affected.

CONCLUSION

Sacral nerve stimulation offers a safe treatment mode in a patient population in whom conservative treatment has failed and traditional surgical approaches would have limited success. The high predictive value of the diagnostic approach offers a unique therapeutic advantage.

Sacral nerve stimulation for faecal incontinence in the UK

Background

Sacral nerve stimulation (SNS) is an effective therapy for faecal incontinence. Published studies derive largely from single centres and there is a need to determine the broader applicability of this procedure.

Methods

Prospective data were collected for all patients undergoing SNS in the UK. Records were reviewed to determine the outcome of treatment.

Results

In three UK centres 59 patients underwent peripheral nerve evaluation, with 46 (78 per cent) proceeding to permanent implantation. Of these 46 patients (40 women) all but two had improved continence at a median of 12 (range 1–72) months. Faecal incontinence improved from a median (range) of 7·5 (1–78) to 1 (0–39) episodes per week (P &lt; 0·001). Urgency improved in all but five of 39 patients in whom ability to defer defaecation was determined, improving from a median of 1 (range 0–5) to 10 (range from 1 to more than 15) min (P &lt; 0·001). Maximum anal squeeze pressure and sensory function to rectal distension changed significantly. Significant improvement occurred in general health (P = 0·024), mental health (P = 0·008), emotional role (P = 0·034), social function (P = 0·013) and vitality (P = 0·009) subscales of the Short Form 36 health survey questionnaire. There were no major complications. One implant was removed.

Conclusion

SNS is a safe and effective treatment, in the medium to long term, for faecal incontinence when conservative treatment has failed.

A review of sacral nerve stimulation for the treatment of faecal incontinence

Sacral nerve stimulation is an emerging surgical technique that uses chronic low-level electrical stimulation, applied to the nerves of the sacral plexus, to produce a clinically beneficial physiological effect on the lower bowel, pelvic floor and anal canal. Faecal incontinence is common, maximal conservative therapy may improve some patients but many require surgery. Results are variable and often unsatisfactory and further options are limited, the traditional end-point being the formation of a colostomy. Sacral nerve stimulation appears to be an alternative treatment that is successful, has low morbidity, is maintained in the medium term and associated with an improved quality of life. The technique has the advantage of a minimally invasive test procedure with high predictive value and the surgery is minor. The underlying mechanism of action although predominately neurological in nature remains to be determined. Precise patient selection is currently unclear however, results are superior to other techniques.

Novel surgical approaches to fecal incontinence: neurostimulation and artificial anal sphincter

Neurostimulation, neosphincters with neurostimulation, and implanted artificial sphincters are recently developed therapeutic options for patients with end-stage fecal incontinence. Of these approaches, sacral nerve electric stimulation appears to be the most promising because of its relative simplicity and low morbidity. However, it is best suited for patients with anatomically intact sphincters. The other procedures target patients with gross structural defects in the sphincter but are still in their infancy. In this article we discuss these techniques and review their rationale, mechanisms of action, indications, outcomes, and complications.

Effect of sacral nerve stimulation on autonomic nerve function

Background

Sacral nerve stimulation has been used successfully to treat motility disorders of the bladder and bowel. The mechanism of action remains unknown. This study examined the effect of stimulation on rectal blood flow as a measure of autonomic nerve function.

Methods

Sixteen patients (15 women) of median age 59 (range 38–71) years were studied. All had undergone permanent electrode implantation for faecal incontinence, a median of 27 (range 2–62) months previously, with clinical benefit. Rectal laser Doppler flowmetry was performed at the level of chronic stimulation, without stimulation, and then at 0·1-V stepwise increments between zero and 1·0 V, and at 1-V increments to 5 V.

Results

There was a significant difference in the median flux between no stimulation and chronic stimulation: 545 (range 355–887) versus 869 (range 507–989) flux units (P = 0·001). Stepwise increments of 0·1 V, between zero and 1·0 V, caused a significant immediate rise in flux (P &lt; 0·001). Further increments did not result in any further significant increase.

Conclusion

Chronic sacral nerve stimulation has a significant effect on rectal blood flow and the autonomic innervation of the distal bowel. The response is rapidly reversible and varies in a dose-dependent manner up to a level of stimulation of 1·0 V.

Surgical intervention for faecal incontinence in women: an update

PURPOSE OF REVIEW

In this review we intend to overview the operations available for faecal incontinence with particular reference to recently published articles.

RECENT FINDINGS

Operations benefiting faecal incontinence in women are direct sphincter repair, dynamic graciloplasty, artificial anal sphincter and sacral nerve stimulation. Considerable benefit was demonstrated with these operations but not without complications. Studies with longer follow-up are required for better assessment of these operations.

SUMMARY

Surgery for faecal incontinence is indicated after failure of non-operative measures. Good results may be achieved.

Permanent sacral nerve stimulation for treatment of idiopathic constipation

BACKGROUND

Constipation can usually be managed using conservative therapies. A proportion of patients require more intensive treatment. Surgery provides variable results. This paper describes an alternative approach, in which the neural control of the bowel and pelvic floor is modified, using permanent sacral nerve stimulation.

METHODS

Four women (aged 27-36 years), underwent temporary and then permanent stimulation. All had idiopathic constipation, resistant to maximal therapy, with symptoms for 8-32 years. Clinical evaluation, bowel diary, Wexner constipation score, symptom analogue score, quality of life questionnaire and anorectal physiology were completed.

RESULTS

There was a marked improvement in all patients with temporary, and in three with permanent, stimulation. Median follow-up was 8 (range 1-11) months. Bowel frequency increased from 1-6 to 6-28 evacuations per 3 weeks. Improvement occurred, at longest-follow-up, in median (range) evacuation score (4 (0-4) versus 1 (0-4)), time with abdominal pain (98 (95-100) versus 12 (0-100) per cent), time with bloating (100 (95-100) versus 12 (5-100) per cent), Wexner score (21 (20-22) versus 9 (1-20)), analogue score (22 (16-32) versus 80 (20-98)) and quality of life. Maximum anal resting and squeeze pressures increased. Rectal sensation was altered. Transit time normalized in one patient.

CONCLUSION

Permanent sacral nerve stimulation can be used to treat patients with resistant idiopathic constipation.

Medium-term results of permanent sacral nerve stimulation for faecal incontinence

BACKGROUND

Anal sphincter surgery for faecal incontinence is associated with significant morbidity and a variable outcome. Sacral nerve stimulation may provide a good functional outcome with minimal morbidity. This paper reports the experience in a single centre over 5 years.

METHODS

Fifteen consecutive patients (14 women), median age 60 (range 37-71) years, underwent temporary, and subsequent permanent, stimulation. All had incontinence to solid or liquid stool; the aetiology was obstetric injury (seven patients), scleroderma (four), idiopathic (two), fistula surgery (one) and repaired rectal prolapse (one). Median duration of symptoms was 6 (range 2-15) years. Clinical evaluation, endoanal ultrasonography, bowel diary, quality of life questionnaire (Short Form (SF) 36) and anorectal physiological testing were performed before and after stimulation.

RESULTS

Continence had improved in all patients at median follow-up of 24 (range 3-60) months. Eleven patients were fully continent. Episodes of faecal incontinence decreased from median (range) 11 (2-30) per week before stimulation to 0 (0-4) per week after permanent stimulation (P < 0.001). Urgency improved in all patients (median (range) ability to defer less than 1 (0-1) versus 8 (1-15) min; P = 0.01). 'Social function' and 'role-physical' subscales of the SF36 improved significantly. Mean resting pressure (35 versus 49 cmH2O with temporary stimulation; P < 0.05) and squeeze pressure increment (43 versus 69 cmH2O with permanent stimulation; P < 0.01) increased. Rectal sensitivity to initial distension changed (mean 47 versus 34 ml air; P < 0.05). There were no major complications.

CONCLUSION

Sacral nerve stimulation is a safe and effective treatment for faecal incontinence when conventional treatment has failed. There is minimal morbidity. The benefit is maintained in the medium term.

Recent innovations in the management of fecal incontinence

The importance of having a reproducible scoring system to objectively assess the severity of fecal incontinence and its response to treatment is stressed, and a number of methods are described. The approach to conservative treatment and investigation is outlined. Recent advances in the surgical management of fecal incontinence including the electrically stimulated gracilis neosphincter, sacral nerve stimulation, the artificial anal sphincter, internal anal sphincter augmentation, rectal augmentation, and antegrade colonic irrigation are described in detail.