Sacral Nerve Stimulation for Fecal Incontinence: External Anal Sphincter Defect <Emphasis Type="Italic">vs</Emphasis>. Intact Anal Sphincter

Purpose  This prospective study was designed to assess the effectiveness of sacral nerve stimulation for fecal incontinence in patients with external anal sphincter defect and to evaluate its efficacy regarding presence and size of sphincter defect. Methods  Fifty-three consecutive patients who underwent sacral nerve stimulation for fecal incontinence were divided into two groups: external anal sphincter defect group (n = 21) vs. intact sphincter group (n = 32). Follow-up was performed at 3, 6, and 12 months with anorectal physiology, Wexner’s score, bowel diary, and quality of life questionnaires. Results  The external anal sphincter defect group (defect <90°:defect 90°–120° = 11:10) and intact sphincter group were comparable with regard to age (mean, 63 vs. 63.6) and sex. Incidence of internal anal sphincter defect and pudendal neuropathy was similar. All 53 patients benefited from sacral nerve stimulation. Weekly incontinent episodes decreased from 13.8 to 5 (P < 0.0001) for patients with external anal sphincter defects and from 6.7 to 2 (P = 0.001) for patients with intact sphincter at 12-month follow-up. Quality of life scores improved in both groups (P < 0.0125). There was no significant difference in improvement in functional outcomes after sacral nerve stimulation between patients with or without external anal sphincter defects. Clinical benefit of sacral nerve stimulation was similar among patients with external anal sphincter defects, irrespective of its size. Presence of pudendal neuropathy did not affect outcome of neurostimulation. Conclusions  Sacral nerve stimulation for fecal incontinence is as effective in patients with external anal sphincter defects as those with intact sphincter and the result is similar for defect size up to 120° of circumference. ^†Deceased.     

Sacral Nerve Stimulation is more Effective than Optimal Medical Therapy for Severe Fecal Incontinence: A Randomized,Controlled Study

Purpose This randomized study was designed to compare the effect of sacral neuromodulation with optimal medical therapy in patients with severe fecal incontinence. Methods Patients (aged 39–86 years) with severe fecal incontinence were randomized to have sacral nerve stimulation (SNS group; n = 60) or best supportive therapy (control; n = 60), which consisted of pelvic floor exercises, bulking agent, and dietary manipulation. Full assessment included endoanal ultrasound, anorectal physiology, two-week bowel diary, and fecal incontinence quality of life index. The follow-up duration was 12 months. Results The sacral nerve stimulation group was similar to the control group with regard to gender (F:M = 11:1 vs. 14:1) and age (mean, 63.9 vs. 63 years). The incidence of a defect of ≤ 120° of the external anal sphincter and pudendal neuropathy was similar between the groups. Trial screening improved incontinent episodes by more than 50 percent in 54 patients (90 percent). Full-stage sacral nerve stimulation was performed in 53 of these 54 “successful” patients. There were no septic complications. With sacral nerve stimulation, mean incontinent episodes per week decreased from 9.5 to 3.1 (P < 0.0001) and mean incontinent days per week from 3.3 to 1 (P < 0.0001). Perfect continence was accomplished in 25 patients (47.2 percent). In the sacral nerve stimulation group, there was a significant (P < 0.0001) improvement in fecal incontinence quality of life index in all four domains. By contrast, there was no significant improvement in fecal continence and the fecal incontinence quality of life scores in the control group. Conclusions Sacral neuromodulation significantly improved the outcome in patients with severe fecal incontinence compared with the control group undergoing optimal medical therapy. *Deceased. Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, June 2 to 6, 2007.     

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 H₂O to 38 (range, 0–111) cm H₂O (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. Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005.     

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 α-adrenergic but not the cholinergic pathway at least partially mediates the excitatory effect of anal electric stimulation. Presented at the meeting of Digestive Disease Week, Chicago, Illinois, May 14 to 19, 2005.     

Sacral Nerve Stimulation for Fecal Incontinence Related to Obstetric Anal Sphincter Damage

Purpose Sphincter repair is the standard treatment for fecal incontinence secondary to obstetric external anal sphincter damage; however, the results of this treatment deteriorate over time. Sacral nerve stimulation has become an established therapy for fecal incontinence in patients with intact sphincter muscles. This study investigated its efficacy as a treatment for patients with obstetric-related incontinence. Methods Fecally incontinent patients with external sphincter defects who would normally have undergone overlapping sphincter repair as a primary or repeat procedure were included. Eight consecutive women (median age, 46 (range, 35–67) years) completed temporary screening; all eventually had permanent implantation. Results Six of eight patients had improved continence at median follow-up of 26.5 (range, 6–40) months. Fecal incontinent episodes improved from 5.5 (range, 4.5–18) to 1.5 (range, 0–5.5) episodes per week (P = 0.0078). Urgency improved in five patients, with ability to defer defecation improving from a median of <1 (range, 0–5) minute to 1 to 5 (range, 1 to >15) minutes (P = 0.031, all 8 patients). There was no change in anal manometry or rectal sensation. There was significant improvement in lifestyle, coping/behavior, depression/self-perception, and embarrassment as measured by the American Society of Colon and Rectal Surgery fecal incontinence quality of life score. Conclusions Sacral nerve stimulation is potentially a safe and effective minimally invasive treatment for fecal incontinence in patients with de novo external anal sphincter defects or defects after unsuccessful previous external anal sphincter repair, although numbers remain small. Dr. Michael Kamm is a consultant to and received research support from Medtronic, however, study design, performance, analysis, and reporting have been conducted without the influence of Medtronic.     

Sacral Nerve Stimulation Can Be Successful in Patients With Ultrasound Evidence of External Anal Sphincter Disruption

PURPOSE This study was designed to determine whether patients with fecal incontinence and endoanal ultrasound evidence of anal sphincter disruption may be successfully treated by sacral nerve stimulation.METHODS Five consecutive females with incontinence to solids and endoanal ultrasound evidence of anal sphincter disruption were treated by a two-week trial of sacral nerve stimulation. If successful, patients then proceeded to permanent sacral nerve stimulation implantation.RESULTS Five patients, aged 34 to 56 years, were treated by temporary sacral nerve stimulation. Four had symptoms starting after childbirth. Two had previously had an anterior sphincter repair. After a two-week trial, three females reported full continence and an improvement in all aspects of their Rockwood fecal incontinence quality of life scores. These three females underwent permanent sacral nerve stimulation implantation. The remaining two patients reported no improvement and underwent dynamic graciloplasty or end colostomy respectively.CONCLUSIONS Sacral nerve stimulation may successfully restore bowel continence in some patients with endoanal ultrasound evidence of a defect in their external anal sphincter.     

Use of total parenteral nutrition as a “Medical colostomy” in management of severe lacerations of the sphincter: Report of a case

Summary A case of anal-sphincter injury with total fecal incontinence is presented. The use of total parenteral nutrition (TPN) as a “medical colostomy” is stressed. After four weeks of support by TPN, the perineal wound had healed and successful sphincteroplasty was performed. TPN was used in the postoperative period to delay bowel movements for one week. The general concept of the use of TPN in sphincter injury is presented, giving the surgeon an option in management of these injuries without resorting to a preliminary colostomy.     

Effects of Hysterectomy on Bowel Function: A Three-Year,Prospective Cohort Study

Purpose This study was a prospective evaluation of the long-term effects of hysterectomy on bowel function using self-reported outcome measures on symptoms of constipation, rectal emptying difficulties, and anal incontinence. Methods In this prospective cohort study, 120 consecutive patients undergoing hysterectomy for benign conditions answered a questionnaire on bowel habits and anorectal symptoms preoperatively. Forty-four patients underwent vaginal and 76 abdominal hysterectomy. Follow-up was performed one and three years postoperatively. Data were analyzed by using multivariate regression and nonparametric statistics. Results The bowel and anorectal survey was answered by 115 of 120 patients (96 percent) after one year and 107 of 120 patients (89 percent) after three years. Abdominal hysterectomy was associated with increased anal incontinence symptoms at one-year (P < 0.01) and three-year follow-up (P < 0.01). Vaginal hysterectomy was not associated with increased anal incontinence symptoms at one year follow-up, although there was a significant increase in incontinence symptoms at the three-year follow-up (P < 0.05). Risk factor analysis indicated that a reported history of obstetric sphincter injury was correlated to an increased risk of developing posthysterectomy anal incontinence (odds ratio, 2.07; 95 percent confidence interval, 1.05–2.87; P < 0.05). There was no significant rise in constipation symptoms or rectal emptying difficulties in either cohort through the follow-up. Conclusions Neither abdominal nor vaginal hysterectomy was associated with constipation, aggravation of constipation, or rectal emptying difficulties three years after surgery. Abdominal and vaginal hysterectomy was, however, associated with an increased risk of mild anal incontinence symptoms, and patients with a reported history of obstetric sphincter injury were at particular risk for posthysterectomy fecal incontinence. Supported by funds from the Swedish Society of Medicine.     

Postpartum fecal incontinence is more common in women with irritable bowel syndrome

PURPOSE: Anal sphincter damage can occur during vaginal delivery and may lead to impairment of fecal continence. The aim of this study was to determine the influence of irritable bowel syndrome on symptoms of fecal incontinence following first vaginal delivery. METHODS: A prospective, observational study was performed before delivery, six weeks, and six months following delivery in primiparous women. A bowel function questionnaire was completed, and anal vector manometry, mucosal electrosensitivity, pudendal nerve terminal motor latency, and anal endosonography were performed. A total of 208 women were assessed before and after delivery, and 104 primigravid women were studied after delivery only. A total of 34 of 312 (11 percent) had an existing diagnosis of irritable bowel syndrome. RESULTS: The prevalence of abnormal manometry or endosonography was similar in women with and without irritable bowel syndrome. However, six weeks after delivery, women with irritable bowel syndrome had a higher incidence of defecatory urgency (64 percent) and loss of control of flatus (35 percent) compared with those without (urgency, 10 percent,P<0.001; flatus, 13 percent,P=0.007). The incidence of frank fecal incontinence was similar in the two groups. Women with IBS had increased mucosal sensitivity to electrical stimulation of the upper anal canal both before and after delivery. CONCLUSION: Women with IBS are more likely to experience subjective alteration of fecal continence postpartum compared with the healthy primigravid population, but they are not at increased risk of anal sphincter injury.     

A novel magnetic device to prevent fecal incontinence (preliminary study)

Background and aims In this research we propose an original magnetic device to strengthen the hypo-atonic anal sphincter and prevent fecal incontinence. Methods The device consists in a couple of small magnetic plaques to be surgically inserted in the wall of the anal canal between the external and internal anal sphincters with the opposite polarities face to face, so that, attracting themselves, close the anal lumen. Three couples of magnets made of materials of different magnetic force (neodymium > ferrite > plastoferrite) were evaluated in each of three swine anatomical preparations by measuring the endoanal pressure with a manometric catheter, both before and after magnet implantation. The mean pressures obtained before and after magnet insertion were statistically compared with Student t test. Results The endoanal pressure after the insertion of neodymium magnets was 79.7 ± 13.1 (mean ± SD), after ferrite magnets was 42.1 ± 5.6 mmHg and after plastoferrite magnets was 21.6 ± 4.6 mmHg, all of them significantly higher than the pressure recorded in basal conditions (1.72 ± 0.71 mmHg). Conclusion This research demonstrated that the implantation of a couple of magnets in the wall of the anal canal is able to create a high pressure zone of a value sufficient to prevent fecal incontinence and that the strength of this “dynamic closure” can be modulated by using magnets of various attraction force, so allowing a “tailored correction” of the anal sphincter hypotension.     

Sacral nerve stimulation for treatment of fecal incontinence

PURPOSE: Many patients with fecal incontinence demonstrate a functional deficit of the internal anal sphincter or the external sphincter muscles without any apparent structural defects. Few patients are amenable to repair or substitution of the sphincter. However, sacral nerve stimulation appears to offer a valid treatment option for fecal incontinence. The objectives of this study were: to evaluate the efficacy of temporary stimulation of the sacral nerve roots (percutaneous nerve evaluation) in patients with functional fecal incontinence; to determine the mechanisms of possible improvement; and to evaluate if temporary stimulation could be reproduced and maintained by implanting a permanent neurostimulation system. METHODS: Twenty-three patients with fecal incontinence, 18 females and 5 males, median age of 54.9 years (range 28–71), underwent a percutaneous nerve evaluation test. Eleven patients (47.8 percent) also had urinary disorders: urge incontinence (4), stress incontinence (3), and retention (4). Associated disorders included perineal and rectal pain (1), spastic paraparesis (1), and syringomyelia (1). All patients underwent a preliminary evaluation using stationary anal manovolumetry, pudendal nerve terminal motor latency measurements, and anal ultrasound. A percutaneous electrode for the stimulation of the sacral nerve roots was positioned at the level of the third sacral foramen (S3) in 20 patients and S2 in 2 patients (1 patient missing). Stimulation parameters used were: pulse width 210µsec, frequency 25 Hz, and average amplitude of 2.8 V (range 1–6). The electrode was left in place for a minimum of 7 days. Five patients were successively implanted with a permanent sacral electrode with a stimulation frequency of 16 to 18 Hz and amplitude of 1.1–4.9 V. RESULTS: Seventeen of the 19 patients (89.4 percent) who completed the minimum percutaneous nerve evaluation period of 7 days (median 10.7 (range 7–30)), had a reduction of liquid or solid stool incontinence by more than 50 percent, and fourteen (73.6 percent) were completely continent for stool. The most important changes revealed by manovolumetry were an increase in resting pressure (P<0.001) and voluntary contraction (P=0.041), reduction of initial pressure for first sensation (P=0.049) and urge to defecate (P=0.002), and a reduction of the rectal volume for urge sensation (P=0.006). The percutaneous nerve evaluation results were reproduced at a median follow-up of 19.2 months (range 5 to 37) in the 5 patients who received a permanent implant. CONCLUSIONS: Temporary stimulation of the sacral roots (percutaneous nerve evaluation) can be of help in those patients with fecal incontinence, and the results are reproduced with permanent implantation. The positive effect on continence seems to be derived from not only the direct efferent stimulation on the pelvic floor and the striated sphincter muscle, but also from modulating afferent stimulation of the autonomous neural system, inhibition of the rectal detrusor, activation of the internal anal sphincter, and modulation of sacral reflexes that regulate rectal sensitivity and motility.     

Use of vector volume manometry and endoanal magnetic resonance imaging in the adult female for assessment of anal sphincter dysfunction

PURPOSE: This study compared conventional water-perfused and vector volume anal manometry in female patients with neurogenic fecal incontinence and chronic anal fissure and in healthy female volunteers. We used endoanal magnetic resonance (MR) imaging to measure internal and external sphincter lengths and thicknesses and contrasted these with the manometric findings in the different anorectal conditions. METHODS: One hundred thirty-three female subjects were studied over an eight-month period, including 33 control volunteers, 83 patients with neurogenic fecal incontinence, and 17 patients with chronic anal fissure. Conventional manometry was contrasted with automated vector volume-derived parameters. Endoanal magnetic resonance images were obtained using a previously described internal coil with a 0.5 T Asset scanner measuring quadrantal internal sphincter thickness and averaged coronal internal and external sphincter lengths. RESULTS: There was a statistically significant relationship between parameters measured by conventional manometry and those variables derived from vector volume manometry at rest and squeeze. There was no difference in sectorial vector-derived pressures within any anorectal condition and no correlation between quadrantal internal sphincter thickness measurements and sectorial pressures at rest. Patients with chronic anal fissure and neurogenic fecal incontinence had constitutionally shorter superficial and subcutaneous external sphincters than healthy control subjects (P<0.001). CONCLUSIONS: There is no association between manometric findings and morphologic sphincter measurement; however, the shorter distal external sphincter in patients with fissure might render the lower anal canal relatively unsupported after internal sphincterotomy in the female patient.Poster presentation at the meeting of the Association of Coloproctology of Great Britain and Ireland, Jersey, United Kingdom, June 29 to July 1, 1998.     

Long-term results of electromyographic biofeedback training for fecal incontinence

PURPOSE: The aim of this study was to examine the long-term results of electromyographic biofeedback training in fecal incontinence. METHODS: Thirty-seven patients (1 male) received a customised program of 2 to 11 (median, 3) biofeedback training sessions with an anal plug electromyometer. Nine patients had persistent incontinence after anal sphincter repair, a further 8 patients had postsurgical or partial obstetric damage of the sphincter but no sphincter repair, 9 patients had neurogenic sphincter damage, and 11 patients were classified as having idiopathic fecal incontinence. Duration of voluntary sphincter contraction was measured by anal electromyography (endurance score) before and after treatment. A postal questionnaire was used to investigate the following variables: 1) subjective rating on a four-grade Likert-scale of the overall result of the biofeedback training; 2) incontinence score (maximum score is 18, and 0 indicates no incontinence); and 3) rating of bowel dissatisfaction using a visual analog scale (0 to 10). RESULTS: Twenty-two patients (60 percent) rated the result as very good (n=8) or good (n=14) immediately after the treatment period. Median endurance score improved from 1 to 2 minutes (P<0.0001). Median incontinence score improved from 11 to 7, and bowel dissatisfaction rating improved from 5 to 2.8 (bothP<0.0001). After a median follow-up of 44 (range, 12–59) months, 15 patients (41 percent) still rated the overall result as very good (n=3) or good (n=12). The incontinence score did not change during follow-up. Median bowel dissatisfaction rating deteriorated from 2.8 to 4.2 but remained better than before treatment. Poor early subjective rating and the need for more than three biofeedback sessions were predictive of worsening during follow-up. CONCLUSION: We think it is encouraging that in this study biofeedback treatment for fecal incontinence with an intra-anal plug electrode resulted in a long-term success rate in nearly one-half of the patients.     

Pudendal neuropathy and severity of incontinence but not presence of an anal sphincter defect may determine the response to biofeedback therapy in fecal incontinence

PURPOSE: It has been suggested that the severity of fecal incontinence, the presence of pudendal neuropathy, or an external anal sphincter defect does not preclude clinical improvement with biofeedback therapy. A discrepancy, however, is frequently found between subjective improvement and objective results after biofeedback therapy. Our aim was to assess whether severity of fecal incontinence, presence of pudendal neuropathy, or an external anal sphincter defect could influence the results of manometric parameters after biofeedback therapy in patients with fecal incontinence. METHODS: Biofeedback therapy was used to treat 27 patients with fecal incontinence (25 women; mean age, 53; range, 29–74 years), according to a strict protocol. Manometry, pudendal nerve terminal motor latency, and anal ultrasound were performed in all patients before biofeedback therapy. Manometric evaluation of external anal sphincter function was performed after the biofeedback sessions. RESULTS: Eight of 27 patients had a good clinical response to biofeedback, but with no significant difference in their mean amplitude and duration of squeeze pressure before and after biofeedback. There was no relationship between the clinical results of biofeedback therapy and the initial severity of fecal incontinence, pudendal neuropathy, or external sphincter defect. Patients with severe incontinence (incontinence to solids) and pudendal neuropathy failed to improve the amplitude and duration of their maximum voluntary contraction after biofeedback therapy. Patients with mild fecal incontinence (incontinence to flatus, liquids, or both) (P<0.04), without pudendal neuropathy (P<0.02), or with (P<0.05) and without (P<0.05) external sphincter defect improved their external anal sphincter function after biofeedback therapy. CONCLUSION: In patients with fecal incontinence, the severity of symptoms and pudendal neuropathy should be considered as two factors of poor prognosis of favorable manometric results after biofeedback therapy. Improvement, on the other hand, may be expected after biofeedback therapy despite an external anal sphincter defect.Presented at the XXIst congress of the Societé Internationale Francophone d'Urodynamique, Lisbon, Portugal, May 14 to 16, 1998.     

A new concept of the anatomy of the anal sphincter mechanism and the physiology of defecation

The role of the external and internal anal sphincters in the mechanism of anal continence is presented. The external sphincter induces continence by 1) preventing internal sphincter relaxation, what I have called the “voluntary inhibition action,” and 2) mechanical compression of the rectal neck and anal canal proper. The mechanism of both actions is described. The internal sphincter plays a significant role not only in involuntary, but also in voluntary, continence. The importance of this role in the correction of anal incontinence is clarified. “Stress defecation,” a condition which follows internal sphincter damage, is discussed. A “single loop continence” theory is presented, based on the fact that each of the three loops of the external sphincter has its own innervation, attachment, and direction of muscle bundles; each loop thus acts as a separate sphincter. The clinical application of this theory is presented.     

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. Read at the meeting of the European Society of Coloproctology, Malta, September 26 to 29, 2007.     

Chronic sacral spinal nerve stimulation for fecal incontinence: Long-term results with foramen and cuff electrodes

PURPOSE: Sacral spinal nerve stimulation is a new therapeutic approach for patients with severe fecal incontinence owing to functional deficits of the external anal sphincter. It aims to use the morphologically intact anatomy to recruit residual function. This study evaluates the long-term results of the first patients treated with this novel approach applying two techniques of sacral spinal nerve stimulator implantation. METHODS: Six patients underwent either of two techniques for electrode placement: one closed (electrodes placed through the sacral foramen) and one open (cuff electrodes placed after sacral laminectomy). Follow-up evaluation of their continence status ranged from 5 to 66 months. RESULTS: Incontinence improved in all patients. The percentage of incontinent bowel movements decreased during chronic stimulation from a mean of 40.2 percent to 2.8 percent, and the Wexner score decreased from a mean of 17 to 2. The function of the striated anal sphincter improved during chronic stimulation: maximum squeeze pressure increased from a mean of 48.5 mmHg to 92.7 mmHg, and median squeeze pressure increased from a mean of 37.3 mmHg to 72.5 mmHg. No complications were encountered perioperatively or postoperatively. Two devices had to be removed because of intractable pain, in one patient at the site of the electrode after five months and in the other at the site of the impulse generator after 45 months. CONCLUSION: Long-term sacral spinal nerve stimulation persistently improves continence and increases striated anal sphincter function in patients with fecal incontinence owing to functional deficits, but in whom the striated anal sphincter is morphologically intact. Two different operative approaches can be applied effectively.Supported by grants from Bayerischen Chirurgen e.V., Munich, Germany; Wilhelm Sander Stiftung, Neustadt, Germany; and Bakken Research Center, Medtronic, Maastricht, the Netherlands.A preliminary report of this study was presented as a poster at the meeting of The American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998.     

Bilateral sacral spinal nerve stimulation for fecal incontinence after low anterior rectum resection

BACKGROUND AND AIMS: The somatomotor innervation pattern has been shown to differ in patients undergoing percutaneous nerve evaluation for sacral nerve stimulation. In some patients bilateral stimulation might improve clinical outcome; however, only single-channel pulse generators have until now been available. We report a patient with fecal incontinence after surgery for rectal carcinoma in whom a dual-channel, individually programmable, pulse generator permitted implantation of neurostimulation electrodes bilaterally. PATIENTS AND METHODS: Intractable fecal incontinence developed in a 48-year-old man who underwent low anterior rectum resection, owing mainly to reduced internal anal sphincter function. The morphology of the anal sphincter was without defect. Based on the findings of unilateral and bilateral temporary sacral nerve stimulation the patient underwent placement of foramen electrodes on S4 bilaterally. Both electrodes were connected to a dual-channel impulse generator for permanent low-frequency stimulation. RESULTS: The percentage of incontinent bowel movements decreased during unilateral test stimulation from 37% to 11%, during bilateral test stimulation to 4%, and with chronic bilateral stimulation to 0%. The Wexner continence score improved from 17 preoperatively to 2, and quality of life (ASCRS score) was notably enhanced. Anorectal manometry revealed improved striated anal sphincter function; the internal anal sphincter remained unaffected. CONCLUSION: Sacral nerve stimulation can effectively treat incontinence after rectal resection, and bilateral stimulation can improve the therapeutic effect.     

Effect of Second Vaginal Delivery on Anal Function in Patients at Risk of Occult Anal Sphincter Injury after First Forceps Delivery

Purpose  The study was designed to determine the effect of further vaginal delivery on anal sphincter function in women after apparently uncomplicated primiparous forceps delivery. Methods  Fifty-two secundigravid women whose first child was forceps-assisted were compared with a control group of 20 women who had undergone spontaneous first vaginal delivery. Both groups were studied antenatally and again at 12 weeks after second delivery using a standardized bowel function questionnaire, endoanal ultrasound, and anal manometry. The primary outcome was fecal incontinence score after second delivery. Results  Before second delivery, 20 of 52 (39 percent) of the forceps group and 3 of 20 (15 percent) control subjects (P = 0.103) reported minor alteration in fecal incontinence. Endoanal ultrasound was more frequently abnormal (38/52 (73 percent) vs. 6/20 (30 percent); P = 0.002), and median anal canal squeeze (71 vs. 104 mmHg; P = 0.004) and resting pressures (43 vs. 58 mmHg; P = 0.004) were lower in the forceps group. There was no difference in continence score between first and second delivery for the forceps group (P = 0.19) group or control subjects (P = 0.18). However, 10 of 38 (26 percent) women with an abnormal endoanal ultrasound after first forceps delivery developed new or worsening symptoms after second delivery. Conclusions  One-quarter of women with occult anal sphincter injury after first forceps delivery experienced some minor alteration in fecal continence after the second delivery. Presented at the 23^rd annual meeting of the Society for Maternal Fetal Medicine, San Francisco, California. Supported by the Irish Health Research Board.     

Patterns of Fecal Incontinence After Anal Surgery

PURPOSE Conservative anal surgery, with maximum preservation of the anal sphincters and continence, is becoming increasingly possible with the emergence of new sphincter-sparing treatments. Many surgeons remain skeptical, however, of the nature and impact of incontinence after anal surgery. We aimed to characterize the patterns of anal sphincter injury in patients with fecal incontinence after anal surgery.METHODS We reviewed our fecal incontinence database and studied a subset developing incontinence after anal surgery. Maximum resting and squeeze pressures and the distal high-pressure zone to mid–anal canal resting pressure gradient were evaluated. Anal ultrasounds were evaluated and specific postoperative lesions were characterized.RESULTS Patterns of sphincter injury in 93 patients with fecal incontinence after manual dilation, internal sphincterotomy, fistulotomy, and hemorrhoidectomy were studied. The internal sphincter was almost universally injured, in a pattern specific to the underlying procedure. One-third of patients had a related surgical external sphincter injury. Two-thirds of women had an unrelated obstetric external sphincter injury. The distal resting pressure was typically reduced, with reversal of the normal resting pressure gradient of the anal canal in 89 percent of patients. Maximum squeeze pressure was normal in 52 percent.CONCLUSION Incontinence after anal surgery is characterized by the virtually universal presence of an internal sphincter injury, which is distal in the high-pressure zone, resulting in a reversal of the normal resting pressure gradient in the anal canal. These data support concerns that non–sphincter-sparing anal surgery leads to fecal incontinence and is increasingly difficult to justify given the availability of modern sphincter-sparing approaches.Presented at the meeting of the Association of Coloproctology of Great Britain and Ireland, July 7 to 10, 2003, Edinburgh, United Kingdom.Recipient of the Colon and Rectal Disease Research Foundation prize for best poster.Reprints are not available.