Anorectal sphincter function and rectal barostat study in patients following transanal endoscopic microsurgery

BACKGROUND AND AIMS: This study evaluated the effect of transanal endoscopic microsurgery (TEM) on anorectal sphincter functions and determined the risk factors for anorectal dysfunctions (including incontinence). PATIENTS AND METHODS: A study group of 33 patients with small, mobile rectal tumors (adenoma and carcinoma) located up to 12 cm from the anal verge underwent anorectal motility studies (using pull-through anorectal manometry and rectal barostat) and endoanal ultrasound prior to surgery and 3 weeks and 6 months after TEM; controls were 20 healthy volunteers. RESULTS: Resting and squeeze anal pressures were reduced 3 weeks after TEM. Resting anal pressure remained reduced 6 months after surgery; the changes were related to low preoperative levels and to the internal anal sphincter defects rather than to the procedure duration or the type of surgery. High-pressure zone length and vector volume were decreased 3 weeks after TEM and restored 6 months later. Rectoanal inhibitory reflex, reflex sphincter contraction, rectoanal pressure gradients, threshold and maximal tolerable volume of rectal sensitivity, and compliance were significantly changed 3 weeks after TEM; only rectal wall compliance remained low at 6 months. The rectoanal inhibitory reflex, reflex sphincter contraction, rectal sensitivity, and compliance were related to the extent and type of excision (partial or full thickness). Anal ultrasound revealed internal anal sphincter defects in 29% of patients studied 3 weeks after TEM. Only 76% of patients were fully continent. Disturbed anorectal function (including partial fecal incontinence) was observed in up to 50% of patients at 3 weeks. Partial and moderate anorectal dysfunction was found in 21% patients 6 months after surgery. The main risk factors of anorectal dysfunctions following TEM included: postoperative internal anal sphincter defects, low preoperative resting anal pressure, disturbed rectoanal coordination, extent (>50% of wall circumference) and the depth (full thickness) of tumor excision. CONCLUSION: TEM has a relevant but temporary effect on anorectal motility. As a result of TEM procedures 21% of the patients had disturbed anorectal functions, mostly due to the extent or depth of tumor excision (influencing rectal compliance and rectoanal coordination), and to the sphincter defects lowering resting anal pressure. Preoperative anorectal motility studies and anal ultrasound allow the identification of patients with the risk of postoperative anorectal dysfunctions.     

A prospective non-randomized two-centre study of patients with passive faecal incontinence after birth trauma and patients with soiling after anal surgery, treated by elastomer implants versus rectal irrigation

Aim

This study is a prospective evaluation of patients with passive faecal incontinence and patients with soiling treated by elastomer implants and rectal irrigation.

Patients and methods

Patients with passive faecal incontinence after birth trauma resulting from a defect of the internal sphincter and patients with soiling after previous anal surgery were included. All patients underwent endo-anal ultrasound, magnetic resonance imaging, and anal manometry. The patients with passive faecal incontinence were initially treated by anal sphincter exercises and biofeedback therapy during half a year. The patients completed incontinence scores, a quality of life questionnaire, and a 2-week diary card.

Results

The elastomer group consisted of 30 males and 45 females with a mean age of 53?years (25–77). The rectal irrigation group consisted of 32 males and 43 females with a mean age of 50?years (25–74). At 6?months follow-up, 30 patients with soiling of the rectal irrigation group and only nine patients of the elastomer group were completely cured (p?=?0.02). Only three patients with passive faecal incontinence were cured in the rectal irrigation group and none in the elastomer group. Three distal migrations of elastomer implants required removal at follow-up.

Conclusions

After patients had performed anal sphincter exercises, no clear improvement of passive faecal incontinence was obtained by elastomer implants or rectal irrigation. However, rectal irrigation is far more effective than elastomer implants in patients with soiling.     

Critical reappraisal of anorectal function tests in patients with faecal incontinence who have failed conservative treatment

Objective

Anorectal function tests are often performed in patients with faecal incontinence who have failed conservative treatment. This study was aimed to establish the additive value of performing anorectal function tests in these patients in selecting them for surgery.

Patients and methods

Between 2003 and 2009, all referred patients with faecal incontinence were assessed by a questionnaire, anorectal manometry and anal endosonography. Patients with diarrhea, inflammatory bowel disease, pouches or rectal carcinoma were excluded.

Results

In total, 218 patients were evaluated. Of these, 107 (49%) patients had no sphincter defects, 71 (33%) had small defects and 40 (18%) had large defects. Anorectal manometry could not differentiate between patients with and without sphincter defects. Patients with sphincter defects were only found to have a significantly shorter sphincter length and reduced rectal capacity compared to patients without sphincter defects. Forty-three patients (20%) had a normal anal pressures ≥40?mmHg. Seventeen patients (8%) had also a dyssynergic pelvic floor both on clinical examination and anorectal manometry. Fifteen patients (7%) had a reduced rectal capacity between 65 and 100?ml. There was no difference in anal pressures or the presence of sphincter defects in these patients compared to patients with a rectal capacity >150?ml. There was no correlation between anorectal manometry, endosonography and faecal incontinence severity scores.

Conclusion

In patients with faecal incontinence who have failed conservative treatment, only anal endosonography can reveal sphincter defects. Anorectal manometry should be reserved for patients eligible for surgery to exclude those with suspected dyssynergic floor or reduced rectal capacity.     

Abnormal visceral autonomic innervation in neurogenic faecal incontinence.

Changes of denervation in the anal sphincter striated and smooth muscle in patients with neurogenic faecal incontinence are well established. This study aimed to determine if there is also a more proximal visceral autonomic abnormality. Thirty women with purely neurogenic faecal incontinence (prolonged pudendal nerve latencies and an intact sphincter ring) and 12 patients with neuropathic changes together with an anatomical disruption were studied. Two control groups consisted of 18 healthy volunteer women and 17 women with normal innervation but an anatomically disrupted sphincter. Rectal sensation was assessed using balloon distension and electrical mucosal stimulation, and anal sensation by electrical stimulation. Rectal compliance was studied to determine whether sensory changes were primary or caused by altered rectal wall viscoelastic properties. Anal canal pressure changes in response to both rectal distension and rectal electrical stimulation were measured to assess the intrinsic innervation of the internal anal sphincter. Patients with neurogenic incontinence alone had impaired rectal sensation to distension (53.1 v 31.5 ml, p < 0.05, neurogenic v controls) and to electrical stimulation (24.4 v 14.8 mA, p < 0.005). Patients with neurogenic incontinence and sphincter disruption also showed impaired sensation compared with healthy controls (55.8 ml v 31.5 ml, p < 0.05 and 22.9 mA v 14.8 mA, p < 0.05). Patients with only a disrupted sphincter had normal visceral sensation to both types of testing. Both rectal compliance and the response of the internal anal sphincter to rectal distension and electrical stimulation were normal in all patient groups. This study suggests that there is a visceral sensory abnormality in patients with neurogenic incontinence which is not caused by altered rectal compliance. As evaluated in this study the intrinsic innervation of the internal anal sphincter is not affected in this process.     

Utility of a combined test of anorectal manometry, electromyography, and sensation in determining the mechanism of ''idiopathic'' faecal incontinence.

Combined tests of anorectal manometry, sphincter electromyography and rectal sensation were carried out in 302 patients with faecal incontinence (235 women, 67 men). The results obtained were compared with 65 normal subjects (35 women, 30 men). A mechanism for incontinence was identified in all and the majority of patients had more than one abnormality. Two hundred and seventy eight patients (92%) had a weak external anal sphincter, 185 of these (67%, mostly women) also showed abnormal perineal descent, and 14 women showed clinical evidence of sphincter damage as a result of obstetric trauma. Ten per cent of patients with impaired external anal sphincter contraction showed associated evidence of spinal disease (impaired rectal sensation plus attenuated or enhanced reflex external anal sphincter activity). Unlike the other groups, the 'spinal' group contained equal numbers of men and women. Ninety seven patients (32%) had evidence of a weak internal anal sphincter. The external sphincter was also very weak and 92% of these patients also had perineal descent. Eighty two patients (27%) showed an unstable internal sphincter, characterised by prolonged 'spontaneous' anal relaxation under resting conditions and an abnormal reduction in anal pressure after conscious contraction of the sphincter or an increase in intraabdominal pressure. One hundred and forty two patients (47%) had a hypersensitive rectum associated with enhanced anorectal responses to rectal distension. All these patients had an abnormally weak external sphincter, suggesting that the hypersensitive or 'irritable' rectum should not be regarded as a cause of faecal incontinence unless accompanied by external sphincter weakness. Twenty four patients (8%) showed a normal basal and squeeze pressures and impaired rectal sensation; six showed giant rectal contractions during rectal distension. The results show that idiopathic faecal incontinence is not caused by a single abnormality, and it is suggested that combined anorectal manometry, electromyography, and sensory testing is a useful technique to identify the causes of faecal incontinence and provide a basis for appropriate treatment.     

Pelvic floor neuropathy: a comparative study of diabetes mellitus and idiopathic faecal incontinence.

Twenty one patients with diabetic peripheral neuropathy, 18 with idiopathic faecal incontinence and 11 normal controls were studied with techniques of mucosal electrosensitivity, rectal distension for the quantitative assessment of anorectal sensation, and manometric and electromyographic tests for the assessment of anorectal motor function. An asymptomatic sensorimotor deficit was found in the anal canal of patients with diabetic peripheral neuropathy. Mucosal electrosensitivity thresholds in the anal canal were significantly higher (p less than 0.01 v controls) and fibre density of the external anal sphincter significantly raised (p less than 0.0001 v controls). Anal manometry and pudendal nerve terminal motor latencies were similar to controls. In patients with idiopathic faecal incontinence the tests of sensory and motor function also showed a sensorimotor neuropathy; compared with controls, mucosal electrosensitivity thresholds were significantly higher (p less than 0.002), anal canal resting and maximum squeeze pressures were significantly lower (p less than 0.05 and p less than 0.002 respectively), and pudendal nerve terminal motor latencies and fibre density of the external anal sphincter were significantly raised (both p less than 0.05). Sensory thresholds to rectal distension were similar in all groups. Pelvic floor sensorimotor neuropathy in diabetic patients has several features in common with that of patients with idiopathic faecal incontinence but its functional significance remains uncertain.     

The efficacy and adverse effects of topical phenylephrine for anal incontinence after low anterior resection in patients with rectal cancer

Background Anal incontinence is experienced by some patients with rectal cancer who received low anterior resection. This study was to examine the efficacy and adverse effects of the alpha-1 adrenergic agonist phenylephrine, which causes contraction of the internal anal sphincter and raises the resting pressure in these patients. Patients and methods Thirty-five patients with anal incontinence were treated with 30% phenylephrine or a placebo randomly allocated in a double-blind study. The efficacy of the drug was assessed by changes in the following standardized questionnaire scores: the fecal incontinence severity index (FISI), fecal incontinence quality of life (FIQL) scales, and a global efficacy question. Anal sphincter function was evaluated using anorectal manometry. Results Phenylephrine did not improve either the FISI score or any of the four FIQL scores. Five of 17 (29%) patients reported subjective improvement after phenylephrine compared with 4 of 12 (33%) using the placebo. The maximum resting anal pressure did not differ between baseline and after 4 weeks application of phenylephrine (30.0 to 27.3 mmHg). In the phenylephrine group, allergic dermatitis was developed in five patients and headache in two. Conclusion In the patients with anal incontinence after low anterior resection for rectal cancer, phenylephrine gel did not seem to be helpful in relieving symptoms with some adverse effects.     

Recovery of anal sphincter function following transabdominal repair of rectal prolapse: Cause of improved continence?

Twenty-eight patients with complete rectal prolapse underwent anorectal manometry before and 6 months and 1–2 years after abdominal rectopexy and sigmoid resection in a study of the mechanisms responsible for postoperatively improved anal continence. Preoperatively, 22 patients reported defective anal control. Seven patients (all with minor incontinence) regained normal control and eight other patients achieved improved continence after surgery. Anal resting, squeeze, and voluntary contraction pressures were significantly lower for defective than for normal control, with a significant rise in these pressures at 6 months after the operation, except for those incontinent patients in whom continence was not improved. No further pressure rise was seen later. Improvement of continence was not accompanied by changes in rectal sensation or reflexive functions of the internal anal sphincter. These results suggest that recovery of the resting and voluntary contraction functions of the sphincter muscles was the cause of continence improvement observed after surgery. Anal manometry was unable to predict outcome of function. Therefore, supplementary procedures for restoration of continence are not advisable, although patients with only minor incontinence are likely to regain full continence after rectopexy alone.     

Rectal sensorimotor dysfunction in patients with urge faecal incontinence: evidence from prolonged manometric studies

BACKGROUND AND AIMS: Although external anal sphincter dysfunction is the major cause of urge faecal incontinence, approximately 50% of such patients have evidence of rectal hypersensitivity and report exaggerated stool frequency and urgency. The contribution of rectosigmoid contractile activity to the pathophysiology of this condition is unclear, and thus the relations between symptoms, rectal sensation, and rectosigmoid motor function were investigated. METHODS: Fifty two consecutive patients with urge faecal incontinence, referred to a tertiary surgical centre, and 24 volunteers, underwent comprehensive anorectal physiological investigation, including prolonged rectosigmoid manometry. Patients were classified on the basis of balloon distension thresholds into those with rectal hypersensitivity (n = 27) and those with normal rectal sensation (n = 25). Automated quantitative analysis of overall rectosigmoid contractile activities and, specifically, high amplitude contractions and rectal motor complex activity was performed. RESULTS: External anal sphincter dysfunction was similar in both patient groups. Overall, phasic activity and high amplitude contraction frequency were greater, and rectal motor complex variables significantly altered, in those with rectal hypersensitivity. Symptoms, more prevalent in the rectal hypersensitivity group, were also more often associated with rectosigmoid contractile events. For individuals, reduced compliance and increased rectal motor complex frequency were only observed in patients with rectal hypersensitivity. CONCLUSIONS: We have identified a subset of patients with urge faecal incontinence-namely, those with rectal hypersensitivity-who demonstrated increased symptoms, enhanced perception, reduced compliance, and exaggerated rectosigmoid motor activity. Comprehensive assessment of rectosigmoid sensorimotor function, in addition to evaluation of anal function, should be considered in the investigation of patients with urge faecal incontinence.     

Anorectal pressure gradient and rectal compliance in fecal incontinence

To study whether anorectal pressure gradients discriminated better than standard anal manometry between patients with fecal incontinence and subjects with normal anal function, anorectal pressure gradients were measured during rectal compliance measurements in 36 patients with fecal incontinence and in 22 control subjects. Anal and rectal pressures were measured simultaneously during the rectal compliance measurements. With standard anal manometry, 75% of patients with fecal incontinence had maximal resting pressure within the normal range, and 39% had maximum squeeze pressure within the normal range. Anorectal pressure gradients did not discriminate better between fecal incontinence and normal anal function, since, depending on the parameters used, 61%–100% of the incontinent patients had anorectal pressure gradients within the normal range. Patients with fecal incontinence had lower rectal volumes than controls at constant defecation urge (median 138 ml and 181 ml, P<0.05) and at maximal tolerable volume (median 185 ml and 217 ml, P<0.05). We conclude that measurements of anorectal pressure gradients offer no advantage over standard anal manometry when comparing patients with fecal incontinence to controls. Patients with fecal incontinence have a lower rectal volume tolerability than control subjects with normal anal function. Accepted: 5 June 1998     

Pneumatic Balloon Dilatation for Chronic Anal Fissure: A Prospective, Clinical, Endosonographic, and Manometric Study

PURPOSE Pneumatic balloon dilation has been shown to be effective in the management of chronic anal fissure, but its effect on the anal sphincter has not been fully investigated. The aim of this study was to evaluate prospectively the clinical, anatomic, and functional pattern in a group of patients treated by pneumatic balloon dilation.METHODS A series of 33 consecutive patients suffering from chronic anal fissure underwent pneumatic balloon dilation. Anal manometry and ultrasonography were performed prior to and 6 to 12 months after the treatment. Manometry was accomplished by means of an endoanal 40-mm balloon inflated with a pressure of 1.4 atmospheres that was left in situ for six minutes under local anesthesia. All patients were interviewed daily for three days after surgery and then clinically evaluated between the third and fifth postoperative weeks. Most patients were interviewed after 25.7 ± 8.4 months (mean ± standard deviation). Anal incontinence was evaluated by means of a validated score of 1 to 6.RESULTS The chronic anal fissure healed between the third and fifth weeks in 31 patients (94 percent), who became asymptomatic 2.5 ± 1.4 days after pneumatic balloon dilation. None of them reported anal pain two years after the treatment (n = 20). The first post-pneumatic balloon dilation defecation was painless in 27 cases (82 percent). Two multiparous females (6 percent of the patients) complained of minor transient anal incontinence (score, 3). Chronic anal fissure recurred in one case (3 percent) after treatment. At manometry, the preoperative anal resting pressure decreased from 91 ± 11.2 to 70.5 ± 5.6 and to 78 ± 5.7 mmHg, 6 and 12 months after pneumatic balloon dilation, respectively (P < 0.0001). Anal ultrasonography did not show any significant sphincter defect.CONCLUSIONS Pneumatic balloon dilation seems to be an effective, safe, easy procedure that decreases anal resting pressure without endosonographically detectable significant sphincter damage.     

Relationship between symptoms and disordered continence mechanisms in women with idiopathic faecal incontinence

BACKGROUND AND AIMS: Anal sphincter weakness and rectal sensory disturbances contribute to faecal incontinence (FI). Our aims were to investigate the relationship between symptoms, risk factors, and disordered anorectal and pelvic floor functions in FI. METHODS: In 52 women with "idiopathic" FI and 21 age matched asymptomatic women, we assessed symptoms by standardised questionnaire, anal pressures by manometry, anal sphincter appearance by endoanal ultrasound and magnetic resonance imaging (MRI), pelvic floor motion by dynamic MRI, and rectal compliance and sensation by a barostat. RESULTS: The prevalence of anal sphincter injury (by imaging), reduced anal resting pressure (35% of FI), and reduced squeeze pressures (73% of FI) was higher in FI compared with controls. Puborectalis atrophy (by MRI) was associated (p<0.05) with FI and with impaired anorectal motion during pelvic floor contraction. Volume and pressure thresholds for the desire to defecate were lower, indicating rectal hypersensitivity, in FI. The rectal volume at maximum tolerated pressure (that is, rectal capacity) was reduced in 25% of FI; this volume was associated with the symptom of urge FI (p<0.01) and rectal hypersensitivity (p = 0.02). A combination of predictors (age, body mass index, symptoms, obstetric history, and anal sphincter appearance) explained a substantial proportion of the interindividual variation in anal squeeze pressure (45%) and rectal capacity (35%). CONCLUSIONS: Idiopathic FI in women is a multifactorial disorder resulting from one or more of the following: a disordered pelvic barrier (anal sphincters and puborectalis), or rectal capacity or sensation.     

Rectal augmentation and stimulated gracilis anal neosphincter

PURPOSE: The aim of this study was the development of a procedure which would successfully treat selected patients presenting with incapacitating urgency and fecal incontinence. Some patients presenting with urgency and fecal incontinence, with an intact anorectum but deficient sphincter mechanism, have low rectal compliance. Management is problematic, because correction of the sphincter defect does not abolish the incapacitating urgency caused by rectal hypersensitivity. METHODS: This was a prospective study of three female patients with urgency and fecal incontinence who underwent combined rectal augmentation using a segment of distal ileum and stimulated gracilis anal neosphincter. All patients had low rectal volumes and two exhibited a temporal relationship between high-amplitude (>60 mmHg) rectal pressure waves and urgency on prolonged ambulatory anorectal manometry. RESULTS: Urgency was abolished and continence restored in all individuals. When the level of stimulation was not optimal or had been discontinued, patients experienced only passive incontinence with no urgency. Postoperative physiology revealed elevated thresholds to rectal distention and a reduction in the number of high-amplitude rectal pressure waves in all cases. CONCLUSIONS: Combined rectal augmentation with stimulated gracilis anal neosphincter may be of benefit to some patients with distressing urgency and fecal incontinence not previously helped by current techniques.     

Serial evaluation of anorectal function following low anterior resection of the rectum

Purpose: This prospective study was performed to serially assess the changes in anorectal function after low anterior resection of the rectum, and to elucidate the mechanisms of functional impairment and the recovery process. Materials and methods: Thirty-two patients undergoing low anterior resection for rectal cancer were evaluated prospectively. Standardized interviews concerning anorectal function and physiologic studies consisting of manometry and balloon proctometry were performed preoperatively, then at 1, 3, and 6 months, and 1 year after the operation. Depending on the length of the residual rectum, patients were divided into two groups: (1) shorter than 4 cm (the short group, n = 18), and (2) longer than or equal to 4 cm (the long group, n = 14). Results: Postoperatively, stool frequency increased and urgency to defecate occurred, which continued until 3–6 months had passed and was more remarkable in the short group. Overall incontinence score increased, which was more remarkable in the short group. Anal resting pressure showed a moderate reduction after 3 months, whereas squeeze pressure did not decrease significantly. Rectoanal inhibitory reflex was postoperatively abolished in almost all patients in the short group, which showed nearly no recovery for 1 year. In the long group, it persisted postoperatively in half the cases, and the reflex returned in a few cases within 1 year. Balloon proctometry revealed overall reduction in rectal capacity and compliance. Although the values tended to recover steadily, they did not reach the preoperative level for 1 year. Urgent volume and maximal tolerable volume remarkably declined, which continued for 1 year and for 6 months, respectively. Rectal compliance also decreased considerably, which continued for 6 months. Most values of rectal capacity tended to be smaller in the short group. Conclusion: Impairment of continence after low anterior resection seemed multifactorial, including diminished rectal capacity and compliance, impaired internal anal sphincter tone, and loss of rectoanal inhibitory reflex. Clinical outcome was better and reduction in rectal capacity was less in patients whose rectum remained more than 4 cm. Most of the functional impairments clinically recovered by 6 months postoperation. In the process of clinical recovery of continence, restoration of rectal capacity and compliance and internal anal sphincter tone seemed to contribute a significant degree, while the rectoanal inhibitory reflex did not contribute as much. Accepted: 14 September 1998     

Is there any correlation between objective anal testing,rupture grade,and bowel symptoms after primary repair of obstetric anal sphincter rupture?: an observational cohort study

PURPOSE: The purpose of this study was to investigate the relationships between the grade of anal sphincter rupture, anal sphincter defect, manometry variables, and anal incontinence. METHODS: A total of 132 females with first-time obstetric sphincter rupture were evaluated by transanal ultrasound, manometry, and scoring of bowel symptoms five months after delivery. RESULTS: Anal sphincter rupture and transanal ultrasound grade correlated with each other (rs = 0.427, P = 0.001). Both rupture and transanal ultrasound grade correlated with soiling grade (rs = 0.2, P = 0.03 for both), but in a multiple regression analysis, only transanal ultrasound grade was significant (P = 0.001) as an independent variable. Anal incontinence score correlated with all the manometry variables, but in a multiple regression analysis, only squeeze pressure was significant (P = 0.001, beta = –0.4) as an independent variable. Both anal sphincter rupture and transanal ultrasound grade were correlated with manometry variables, but only transanal ultrasound grade was significant as an independent variable after multiple regression analysis. The frequency of transanal ultrasound–verified extensive defect of anal sphincter was higher in rupture Grade 3B (25; 95 percent confidence interval, 12–38 percent) and Grade 4 (45; 95 percent confidence interval, 24–66 percent) than in Grade 3A (2.8; 95 percent confidence interval, –1 to –6.6 percent). CONCLUSION: Manometry variables are significantly lower in incontinent females than in continent females, and the Wexner incontinence score was correlated with manometry variables. Both anal sphincter rupture and transanal ultrasound grade correlated with soiling grade and with manometry variables, but in both cases only the transanal ultrasound grade was a significant independent variable.     

Anorectal incontinence and rectal prolapse: differential assessment of the innervation to puborectalis and external anal sphincter muscles.

The innervation of the puborectalis and external anal sphincter muscles was studied in 32 patients with idiopathic (neurogenic) faecal incontinence, 12 of whom also had complete rectal prolapse, using transcutaneous spinal stimulation, transrectal pudendal nerve stimulation, single fibre EMG, anorectal manometry, and measurement of perineal descent. Fourteen normal subjects served as controls. Significant increases in the spinal motor latencies from L1 to the puborectalis and external anal sphincter muscles were shown in all 32 incontinent patients (p less than 0.01). The single fibre (EMG) fibre density was increased in the puborectalis muscle in 60% and in the external anal sphincter in 75% of patients. An increased pudendal nerve terminal motor latency was found in 68% of patients; 69% had an abnormal degree of perineal descent and all had reduced anal canal contraction pressures. These data show that the different innervations of the puborectalis and external anal sphincter muscles are both damaged in patients with anorectal incontinence.     

Effects of short term sacral nerve stimulation on anal and rectal function in patients with anal incontinence

BACKGROUND: Some patients with faecal incontinence are not amenable to simple surgical sphincter repair, due to sphincter weakness in the absence of a structural defect. AIMS: To evaluate the efficacy and possible mode of action of short term stimulation of sacral nerves in patients with faecal incontinence and a structurally intact external anal sphincter. PATIENTS: Twelve patients with faecal incontinence for solid or liquid stool at least once per week. METHODS: A stimulating electrode was placed (percutaneously in 10 patients, operatively in two) into the S3 or S4 foramen. The electrode was left in situ for a minimum of one week with chronic stimulation. RESULTS: Evaluable results were obtained in nine patients, with early electrode displacement in the other three. Incontinence ceased in seven of nine patients and improved notably in one; one patient with previous imperforate anus and sacral agenesis had no symptomatic response. Stimulation seemed to enhance maximum squeeze pressure but did not alter resting pressure. The rectum became less sensitive to distension with no change in rectal compliance. Ambulatory studies showed a possible reduction in rectal contractile activity and diminished episodes of spontaneous anal relaxation. CONCLUSIONS: Short term sacral nerve stimulation notably decreases episodes of faecal incontinence. The effect may be mediated via facilitation of striated sphincter muscle function, and via neuromodulation of sacral reflexes which regulate rectal sensitivity and contractility, and anal motility.     

Early effect of external beam radiation therapy on the anal sphincter: A study using anal manometry and transrectal ultrasound

The early effect of pelvic irradiation on the anal sphincter has not been previously investigated. This study prospectively evaluated the acute effect of preoperative radiation on anal function. Twenty patients with rectal carcinoma received 4,500 cGy of preoperative external beam radiation. The field of radiation included the sphincter in 10 patients and was delivered above the anorectal ring in 10 patients. Anal manometry and transrectal ultrasound were performed before and four weeks after radiotherapy. No significant difference in mean maximal squeeze or resting pressure was found after radiation therapy. An increase in mean minimal sensory threshold was significant. Histologic examination revealed minimal radiation changes at the distal margin in 8 of 10 patients who underwent low anterior resection and in 1 of 3 patients who underwent abdominoperineal resection. We conclude that preoperative radiation therapy has minimal immediate effect on the anal sphincter and is not a major contributing factor to postoperative incontinence in patients after sphincter-saving operations for rectal cancer.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991. Winner of the Northwest Society of Colon and Rectal Surgeons Award.     

Clinical, sonographic and manometric characteristics and impact on quality of life of fecal incontinence in 92 men referred for endoanal ultrasonography

Anal incontinence (AI) is a frequent symptom with considerable impact on quality of life. The aim of this study was to describe the clinical, sonographic and manometric characteristics of a male population with AI. MATERIALS AND METHODS: Endoanal ultrasonography (EAU) was performed in 92 men referred for exploration of AI. Anal incontinence severity was evaluated by the Jorge and Wexner score (JW). The gastrointestinal quality-of-life index (GIQLI) was determined in 57% of patients. Anorectal manometry was performed in 62.6% of patients. RESULTS: The average JW score was 11+/-1. Anal incontinence had considerable impact on quality of life: average GIQLI=81+/-4. Seventeen patients presented an anal sphincter defect on EAU, 16 of whom had a history of coloproctological surgery. Prior surgery was significantly more common among patients who had a defect on ultrasonography; manometry showed significantly lower resting anal pressure. CONCLUSION: Our study confirms the severity of AI in a male population and its impact on quality of life. It also highlights the high prevalence of anal sphincter defects in patients with a history of anal surgery.     

Anorectal dysfunction and rectal prolapse in progressive systemic sclerosis

Our aim was to characterize the clinical spectrum of anorectal dysfunction among eight patients with progressive systemic sclerosis (PSS) who presented with altered bowel movements with or without fecal incontinence. The anorectum was assessed by physical examination, proctosigmoidoscopy, and anorectal manometry. There was concomitant involvement of the other regions of the digestive tract in all patients as determined by barium studies, endoscopy, or manometry: eight esophageal, three gastric, four small bowel, and two colonic. Seven patients had fecal incontinence, and four also had second-degree complete rectal prolapse. Abnormal anorectal function, particularly abnormal anal sphincter resting pressures, were detected in all patients; anal sphincter pressures were lower in those with rectal prolapse. Rectal capacity and wall compliance were impaired in seven of seven patients. Successful surgical correction of prolapse in three patients resulted in restoration of incontinence for six months and seven years in two of the three patients. We conclude that rectal dysfunction and weakness of the anal sphincters are important factors contributing, respectively, to altered bowel movements and fecal incontinence in patients with gastrointestinal involvement by PSS. Rectal prolapse worsens anal sphincter dysfunction and should be sought routinely as it is a treatable factor aggravating fecal incontinence in patients with PSS.This work was presented in part at the Annual Meeting of the American Gastroenterological Association, May 1992, and appears in abstract form in Gastroenterology 1992;102:A473.Supported in part by the General Clinical Research Center Grant 00585 from the National Institutes of Health.