Compound muscle action potential of the external anal sphincter.

AIM: Pudendal nerve terminal motor latency (PNTML) assesses distal innervation of the external anal sphincter (EAS) but it is insensitive to early nerve damage. We propose to extend the assessment of PNTML to the measurement of the compound muscle action potential (CMAP) of the EAS to understand its progressive denervation. METHOD: Ninety women with faecal incontinence were prospectively examined and compared with 36 asymptomatic women who acted as controls. PNTML was performed bilaterally and the muscle response analysed for CMAP to include amplitude, area and duration. Anorectal manometry was measured by a station-pull technique using a water-filled microballoon. spss version 11.5 was used for statistical analysis. RESULTS: In asymptomatic women the CMAP on the left side was greater in nulliparous (n = 7) than parous (n = 27, P < 0.05) individuals. There was a positive correlation with maximum squeeze pressure and area on the left side (P < 0.05, r = 0.397). In women with faecal incontinence, CMAP on the left side had a negative correlation with age (n = 75, P < 0.05), there was no correlation with parity or anorectal manometry. Nulliparous asymptomatic women had a greater CMAP (P < 0.05) on the left side than asymptomatic parous women and parous women with faecal incontinence. Right-side measurements were not conclusive. CONCLUSION: Compound muscle action potential demonstrated progressive denervation with age in women with faecal incontinence but did not reliably identify early signs of denervation in asymptomatic women. The area on the left side related to muscle function in asymptomatic women but not in women with faecal incontinence. CMAP can distinguish between parous women with faecal incontinence and nulliparous asymptomatic women but is not a useful test of function of the EAS.

Fatigue rate of the external anal sphincter.

AIM: Studies of skeletal muscle show that fatigue rate corresponds to the proportion of fast-twitch and slow-twitch fibres that are present in the muscle. Limited work has been done on the fatigue rate of the external anal sphincter. We have prospectively studied fatigability of the external anal sphincter in women with faecal incontinence and women with normal bowel control. METHOD: Anorectal manometry was measured by a station-pull technique using a water-filled microballoon. Fatigue rate was calculated from anal pressure measurements taken every 0.1 s over a 20-s squeeze. RESULTS: Women with faecal incontinence (n=88, median -12 cmH(2) O/min) were less susceptible to fatigue than women with normal bowel control (n=36, median -43 cmH(2) O/min) (P<0.01). The external anal sphincter was less susceptible to fatigue with increasing age (P<0.01, r=0.499). In women with normal bowel control and in women with faecal incontinence fatigue rate was negatively correlated with maximum squeeze pressure (P<0.01, r=-0.287; P<0.01, r=-0.579). CONCLUSION: The external anal sphincter was less susceptible to fatigue with increasing age. Women with faecal incontinence have a weaker but more fatigue-resistant external anal sphincter. This might correspond to a higher proportion of slow-twitch muscle fibres. Histological studies are needed to examine this hypothesis.

Anal acoustic reflectometry: a new technique for assessing anal sphincter function.

OBJECTIVE: Anal acoustic reflectometry (AAR) is a new technique that offers an assessment of anal sphincter function by the measurement of additional parameters not available with conventional manometry. The aim of this study is to describe the technique, methodology and initial pilot study results. METHOD: Wideband sounds (100 Hz to 16 kHz) are transmitted into a thin polyurethane bag placed within the anal canal. Calculation of cross-sectional area from reflected sound waves, over a range of pressures (0-200 cm H(2)O) during inflation/deflation of the bag, results in five physiological parameters of anal canal function. Five patients [three continent (two female) and two incontinent (both female)] were assessed with AAR and anal manometry. RESULTS: Anal acoustic reflectometry parameters were reduced in incontinent when compared with continent patients. Resting Opening Pressures (cmH(2)O) were 27 and 16 in patients with faecal incontinence (FI) vs 44 and 72 in continent patients; Resting Opening Elastance (cmH(2)O/mm(2)) was 0.88 and 1.08 in FI patients vs 1.65 and 1.34 in continent patients. The Resting Opening Pressure of a similarly aged continent male (55 cmH(2)O) was greater than three of the females. During assessment of voluntary contraction (one FI female vs one continent female), Squeeze Opening Pressure (cmH(2)O) was 31 vs 100 and Elastance (cmH(2)O/mm(2)) 0.61 vs 2.07. CONCLUSION: Anal acoustic reflectometry appears to be promising technique. Further work is in place to clarify whether it will be useful in clinical assessment of incontinent patients.

The effect of physical activity on pelvic organ prolapse.

OBJECTIVE: The objective of this study was to determine whether pelvic organ prolapse increases after physical activity. DESIGN: Prospective observational study. SETTING: St Mary's Hospital, Manchester, UK. SAMPLE: Women undergoing surgery for pelvic organ prolapse. METHODS: Fifty-four women were recruited to the study. Symptoms and POPQ findings were assessed after a period of prescribed activity and overnight bedrest. MAIN OUTCOME MEASURES: Primary outcome was an increase in Pelvic Organ Prolapse Quantification (POPQ) measurements with activity. Secondary outcomes were association of symptoms or quality-of-life scores (Pelvic Floor Distress Inventory [PFDI] and Pelvic Floor Impact Questionnaire [PFIQ]) with an increase in POPQ measurements. RESULTS: There was a significant increase in POPQ stage and five vaginal parameters (Aa, Ba, C, Ap and Bp) with physical activity (P < 0.001). Reported symptoms, higher PFDI and PFIQ scores and higher individual symptom bother scores were not more common in the women with greater pelvic organ descent (measured by the POPQ system) following physical activity. CONCLUSIONS: Greater pelvic organ prolapse was found on POPQ examination following physical activity, but this was not associated with worsening of symptoms and greater impairment of quality of life.

Liverpool Ultrasound Pictorial Chart: the development of a new method of documenting anal sphincter injury diagnosed by endoanal ultrasound.

OBJECTIVE: To develop and validate a pictorial chart that documents ultrasound examination of the anal sphincter. DESIGN: A new pictorial chart (Liverpool Ultrasound Pictorial Chart [LUPIC]) depicting the normal anatomy of the anal sphincter was developed. METHODS: To validate LUPIC, two observers documented the findings of 296 endoanal scans. Reliability was assessed between observers using kappa agreement for presence and position of sphincter defects. To validate the use of LUPIC by different observers, a video of ten endoanal ultrasound scans was reviewed by our local expert (gold standard). Seven clinicians underwent test-retest analysis. Kappa agreement was calculated to assess intra-observer and gold standard versus observer agreement for the overall presence of sphincter defects and compared with the gold standard. Complete agreement for the position and level of sphincter defects was assessed for the five abnormal scans. MAIN OUTCOME MEASURES: Excellent agreement between the two observers was found for the presence (kappa 0.99), position and level of external anal sphincter defects documented using LUPIC. The intra-observer and gold standard versus observer kappa values of experienced clinicians (A-E) showed good agreement for the overall presence of sphincter defects. Complete agreement for the position and level of sphincter defects was found in 23 of 35 (66%) observations. CONCLUSIONS: LUPIC is designed and validated method of documenting anal sphincter injury diagnosed by endoanal ultrasound. Standardisation of endoanal ultrasound findings by using LUPIC may help correlate the degree of damage with patient symptoms.

Electrical stimulation for faecal incontinence in adults.

BACKGROUND: Faecal incontinence is a particularly embarrassing and distressing condition with significant medical, social and economic implications. Electrical stimulation has been used with apparent success in the treatment of faecal incontinence. However, standards of treatment are still lacking and the magnitude of alleged benefits has yet to be established. OBJECTIVES: To determine the effects of electrical stimulation for the treatment of faecal incontinence in adults. SEARCH STRATEGY: We searched the Cochrane Incontinence Group Specialised Trials Register (searched 13 March 2007) and reference lists of potentially eligible articles. SELECTION CRITERIA: All randomised or quasi-randomised trials evaluating electrical stimulation in adults with faecal incontinence. DATA COLLECTION AND ANALYSIS: Two reviewers assessed the methodological quality of potentially eligible trials and independently extracted data from the included trials. A wide range of outcome measures were considered. MAIN RESULTS: Four eligible trials with 260 participants were identified. Findings from one trial suggest that electrical stimulation with anal biofeedback and exercises provides more short-term benefits than vaginal biofeedback and exercises for women with obstetric-related faecal incontinence. Another study found contradictory results, with no added benefit from electrical stimulation over biofeedback and exercises alone. Although all trials report that patient's symptoms are generally improved, it is not clear that this is the effect of electrical stimulation. No further conclusions could be drawn from the data available. AUTHORS' CONCLUSIONS: At present, there are insufficient data to allow reliable conclusions to be drawn on the effects of electrical stimulation in the management of faecal incontinence. There is a suggestion that electrical stimulation may have a therapeutic effect, but this is not certain. Larger, more generalisable trials are needed.

A valsalvometer can be effective in standardising the Valsalva manoeuvre.

A prospective randomised controlled study was performed in order to study the effectiveness of a device designed to reduce the variability in intra-abdominal pressures generated by individuals performing the Valsalva manoeuvre. One hundred women were recruited to take part in the project which compared a traditional Valsalva manoeuvre following standardised verbal instruction with forced expiration through a flow restriction device called a "valsalvometer". The abdominal pressure was measured using an air-filled rectal balloon catheter linked to a pressure transducer. The use of the valsalvometer was associated with a reduction in variation of intra-abdominal pressure between women to 50% of the standard deviation. The new device has the capacity to reduce the variation in intra-abdominal pressure produced when performing the Valsalva manoeuvre. The rise in intra-abdominal pressure may act as a standard against which other measurements are made.

Investigation of stimulus position in the production of the strength duration curve of the external anal sphincter muscle in women with anorectal dysfunction.

OBJECTIVE: The strength duration test (SDT) is a minimally invasive test of the innervation of a muscle and has been successfully adapted for use on the external anal sphincter (EAS). The SDT has previously been performed on the EAS placing a stimulating probe in the 3 o'clock position. The aim of this study was to determine whether there was any variation in the strength duration curves (SDC) produced at different positions around the EAS. PATIENTS AND METHODS: Thirty-one patients with anorectal dysfunction attended our Institution for Anorectal Physiology Studies and were recruited to the study. After undergoing anal manometry, pudendal nerve terminal motor latency measurement and endoanal ultrasonography, the SDT was performed in four stimulus positions (3, 6, 9 and 12 o'clock). The sequence of positions was randomly selected. RESULTS: Four SDCs were obtained successfully in 25 patients. There was no significant difference seen between the four positions at the longer current durations (1-100 ms). Significant differences occurred at the shortest current durations (0.3 and 0.1 ms) when comparing adjacent stimulus positions except between the 6 and 9 o'clock positions, which were comparable. When opposing positions were compared (3-9 and 6-12 o'clock) at these short durations no significant difference was found. CONCLUSION: There was no significant difference between the SDC produced at 3 and 9 o'clock. These positions closely correspond to where the pudendal nerves enter the EAS. It therefore appears acceptable to perform the SDT in either of these positions, though 3 o'clock remains our preferred position.

Biofeedback and/or sphincter exercises for the treatment of faecal incontinence in adults.

BACKGROUND: Faecal incontinence is a particularly embarrassing and distressing condition with significant medical, social and economic implications. Anal sphincter exercises and biofeedback therapy have been used to treat the symptoms of people with faecal incontinence. However, standards of treatment are still lacking and the magnitude of alleged benefits has yet to be established. OBJECTIVES: To determine the effects of biofeedback and/or anal sphincter exercises/pelvic floor muscle training for the treatment of faecal incontinence in adults. SEARCH STRATEGY: We searched the Cochrane Incontinence Group Specialised Trials Register (searched 27 February 2006) and the reference lists of relevant articles. SELECTION CRITERIA: All randomised or quasi-randomised trials evaluating biofeedback and/or anal sphincter exercises in adults with faecal incontinence. DATA COLLECTION AND ANALYSIS: Two reviewers assessed the methodological quality of eligible trials and two reviewers independently extracted data from included trials. A wide range of outcome measures were considered. MAIN RESULTS: Eleven eligible studies were identified with a total of 564 participants. In all but three trials methodological quality was poor or uncertain. No study reported a major difference in outcome between any method of biofeedback or exercises and any other method, or compared to other conservative management. There are suggestions that rectal volume discrimination training improves continence more than sham training and that anal biofeedback combined with exercises and electrical stimulation provides more short-term benefits than vaginal biofeedback and exercises for women with obstetric-related faecal incontinence. Further conclusions are not warranted from the available data. AUTHORS' CONCLUSIONS: The limited number of identified trials together with their methodological weaknesses do not allow a definitive assessment of the possible role of anal sphincter exercises and biofeedback therapy in the management of people with faecal incontinence. We found no evidence of biofeedback or exercises enhancing the outcome of treatment compared to other conservative management methods. While there is a suggestion that some elements of biofeedback therapy and sphincter exercises may have a therapeutic effect, this is not certain. Larger well-designed trials are needed to enable safe conclusions.

Routine symptom screening for postnatal urinary and anal incontinence in new mothers from a district.

Parous middle-aged women present with urinary and faecal incontinence and childbirth trauma is thought to be a causal factor. Both symptoms are common after childbirth but usually go under-reported. It has been suggested that new mothers are likely to benefit from routine symptom screening because by actively identifying symptomatic women they could then be helped to access continence services. The main objective of this study was to pilot a programme of routine symptom screening for postnatal urinary and anal incontinence in new mothers from a district general hospital. Self-completion questionnaires for both urinary and anal incontinence were sent by post to 442 primiparous women who had delivered consecutively 10 months previously in a district general hospital. Two hundred and seventy-five new mothers responded to the survey. Ninety-two women had new symptoms of incontinence at 10 months, 82 had urinary incontinence and 25 had anal incontinence. However, only six new mothers had discussed the problem with a health professional. Although nine women requested a hospital appointment none of the women attended the appointment arranged for them. The domain scores on both questionnaires were significantly less for symptomatic new mothers when compared to women with established symptoms of incontinence. The programme of screening successfully identified women with symptoms of incontinence. However, all of the symptomatic women declined a follow-up appointment at hospital which questions the benefits of routine screening 10 months after childbirth.

The strength duration test: a novel tool in the identification of occult neuropathy in women with pelvic floor dysfunction.

OBJECTIVE: The Strength-duration test (SDT) is a simple minimally invasive measure of muscle innervation, recently adapted for the assessment of the external anal sphincter (EAS). This test can discriminate women with faecal incontinence from controls. The purpose of this study was to determine if the SDT could detect denervation of the EAS in women with weak but anatomically intact EAS and normal pudendal nerve terminal motor latency (PNTML). PATIENTS AND METHODS: Thirteen women with weak but intact EAS on endoanal ultrasound (EAUS) with normal maximum resting pressure and PNTML were recruited to undergo the SDT. The results from this group were compared to control data for the SDT previously collected in our unit. RESULTS: Nine of 13 women were found to have SDT above a 95% confidence interval of the mean curve for controls and six had a SDT outside a 90% confidence interval for individuals derived from control data, suggesting denervation of the EAS. The mean area under the curve was significantly higher in our study group compared to controls (91.0 microsmA vs 72.2 microsmA, P = 0.047) as was the current intensity measured at the 1 ms pulse duration (18.2 mA vs 12.94 mA, P = 0.048), typical of denervation with this test. CONCLUSION: The SDT was abnormal in nine of the 13 study patients. This may partly explain reduced maximum voluntary contraction seen in this group of patients. SDT may be a more sensitive tool in detecting neuropathy than latency measurement.

Fatigability of the external anal sphincter in anal incontinence.

INTRODUCTION: Anal incontinence commonly results from external anal sphincter dysfunction. The muscle is routinely assessed by anorectal physiology studies. Fatigability is not routinely measured but should be an important factor in the maintenance of continence. The fatigue rate index has been developed to address this. The purpose of this study was to investigate the fatigability of the external anal sphincter in incontinent patients compared with that in controls and to determine its correlation with symptom severity and pudendal nerve terminal motor latency measurement. METHODS: Forty-two patients with anal incontinence (33 female, 9 male) and 20 control patients (17 female, 3 male) were studied. As part of anorectal physiology studies, manometry was measured by a station pull-through technique with a closed-system microballoon. After a rest period of one minute, fatigue was measured over a 20-second squeeze at 1.5 cm in the anal canal with two consecutive readings separated by a further one-minute rest period. The fatigue rate index was calculated from the maximum squeeze pressure and fatigue rate. A validated symptom severity scoring system was used to assess symptomatology in patients with anal incontinence. RESULTS: No difference was detected in demographic factors between the two groups. The fatigue rate index was significantly different between the control and incontinent groups (1.85 vs. 0.67 minutes, P = 0.001). No other factors were significantly different between the two groups (maximum squeeze pressure, 89.1 vs. 79 cm H(2)O, P = 0.42; fatigue rate, -85.8 vs. -101.2 cm H(2)O/min, P = 0.62). The fatigue rate index demonstrated a significant correlation with symptom score ( r = -0.44, P = 0.005). The fatigue rate index did not correlate with latency measurement. CONCLUSIONS: A significant difference was detected in the fatigue rate index between incontinent and control patients. The Fatigue Rate Index demonstrated a significant correlation with symptom severity score and it may be a useful discriminating measure of external anal sphincter function.

Strength-duration testing of the external anal sphincter in females with anorectal dysfunction.

PURPOSE: The strength-duration test has been suggested as a means of assessing external anal sphincter function. This study was designed to investigate this claim by comparing the strength-duration test with established measures of external anal sphincter function. METHODS: Forty-nine females undergoing diagnostic anorectal testing (manometry, rectal sensation, electromyogram, pudendal nerve terminal motor latency, and endoanal ultrasound) also had the strength-duration test performed (which was repeated for each patient after a short rest period). RESULTS: The strength-duration test was repeatable. Statistically significant correlations were found between this test at pulse durations of 3 ms, 1 ms, and 0.3 ms with electromyographic activity of the external anal sphincter and with pressure in the anal canal during voluntary contraction. Significant correlations were found for durations of 100 ms, 30 ms, 10 ms, and 3 ms with the pudendal nerve terminal motor latency on the right and for the 3 ms and 0.3 ms durations with latency on the left. There were no correlations between the strength-duration test and resting pressure in the anal canal. CONCLUSION: The strength-duration test significantly correlates with the established measures of external anal sphincter function and its innervation. Therefore, this simple test appears to provide a simple measure of external anal sphincter denervation.

A new condition-specific health-related quality of life questionnaire for the assessment of women with anal incontinence.

OBJECTIVE: To design and validate a condition-specific health-related quality of life questionnaire for the assessment of women with anal incontinence. DESIGN: A psychometric study by postal survey. SETTING: South Manchester University Hospital, UK. SAMPLE: Two hundred and twenty women with known anal incontinence. METHOD: The questionnaire was adapted from the King's Health Questionnaire, a condition-specific health-related quality of life questionnaire for the assessment of women with urinary incontinence. The questionnaire was then tested for acceptability, reliability and validity by postal survey. RESULTS: The Manchester Health Questionnaire was found to be highly acceptable to women and showed excellent internal consistency, test-retest reliability, criterion and construct validity. CONCLUSION: The questionnaire is both a valid and reliable instrument for the assessment of health-related quality of life among women with anal incontinence. It will be useful in many different clinical settings and be of practical use in the evaluation of women after childbirth. As the good response rates show it could be a successful part of a postal survey.

An evaluation of the efficacy of in-patient bladder retraining.

This is a retrospective review of 50 consecutive patients with urinary frequency, urgency and urge incontinence, admitted in 1995 and early 1996 for bladder retraining in the form of timed voiding. At discharge 80% of the women were subjectively cured or satisfactorily improved, but this was significantly reduced to 32% of the 37 who replied to a postal survey between 12 and 29 months (mean interval 21.3 months) later. There were no significant associations between outcome and urodynamic diagnosis, reduced cystometric capacity, length of symptomatology, previous treatment or requirement for additional therapy, but this may have been in part due to small numbers. In conclusion, bladder retraining is a method of treatment for patients with both sensory urgency and detrusor instability which appears to be at least as successful as other modes of treatment for these conditions.

Electrical stimulation for faecal incontinence in adults.

BACKGROUND: Faecal incontinence is a particularly embarrassing and distressing condition with significant medical, social and economic implications. Electrical stimulation has been used with apparent success in the treatment of faecal incontinence. However, standards of treatment are still lacking and the magnitude of alleged benefits has yet to be established. OBJECTIVES: To determine the effects of electrical stimulation for the treatment of faecal incontinence in adults. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register, the Cochrane Controlled Trials Register, Medline, Embase and reference lists of potentially eligible articles up to November 1999. Date of the most recent searches: November 1999. SELECTION CRITERIA: All randomised or quasi-randomised trials evaluating electrical stimulation in adults with faecal incontinence. DATA COLLECTION AND ANALYSIS: Three reviewers assessed the methodological quality of potentially eligible trials and two reviewers independently extracted data from the included trial. A wide range of outcome measures were considered. MAIN RESULTS: Only one eligible trial with 40 participants was identified. It was a randomised trial, but it suffered from methodological drawbacks and did not follow up patients beyond the end of the trial period. Findings from this trial suggest that electrical stimulation with anal biofeedback and exercises provides more short-term benefits than vaginal biofeedback and exercises for women with obstetric-related faecal incontinence. No further conclusions could be drawn from the data available. REVIEWER'S CONCLUSIONS: At present, there are insufficient data to allow reliable conclusions to be drawn on the effects of electrical stimulation in the management of faecal incontinence. There is a suggestion that electrical stimulation may have a therapeutic effect, but this is not certain. Larger, more generalisable trials are needed.

Biofeedback and/or sphincter exercises for the treatment of faecal incontinence in adults.

BACKGROUND: Faecal incontinence is a particularly embarrassing and distressing condition with significant medical, social and economic implications. Sphincter exercises and biofeedback therapy have been used to treat the symptoms of people with faecal incontinence. However, standards of treatment are still lacking and the magnitude of alleged benefits has yet to be established. OBJECTIVES: To determine the effects of biofeedback and/or anal sphincter exercises/pelvic floor muscle training for the treatment of faecal incontinence in adults. SEARCH STRATEGY: We searched the Cochrane Incontinence Group trials register, the Cochrane Controlled Trials Register, Medline, Embase and all reference lists of relevant articles up to November 1999. Date of the most recent searches: November 1999. SELECTION CRITERIA: All randomised or quasi-randomised trials evaluating biofeedback and/or anal sphincter exercises in adults with faecal incontinence. DATA COLLECTION AND ANALYSIS: Three reviewers assessed the methodological quality of eligible trials and two reviewers independently extracted data from included trials. A wide range of outcome measures were considered. MAIN RESULTS: Only five eligible studies were identified with a total of 109 participants. In the majority of trials methodological quality was poor or uncertain. All trials were small and employed a limited range of outcome measures. Follow-up information was not consistently reported amongst trials. Only two trials provided data in a form suitable for statistical analyses. There are suggestions that rectal volume discrimination training improves continence more than sham training and that anal biofeedback combined with exercises and electrical stimulation provides more short-term benefits than vaginal biofeedback and exercises for women with obstetric-related faecal incontinence. Further conclusions are not warranted from the available data. REVIEWER'S CONCLUSIONS: The limited number of identified trials together with their methodological weaknesses do not allow a reliable assessment of the possible role of sphincter exercises and biofeedback therapy in the management of people with faecal incontinence. There is a suggestions that some elements of biofeedback therapy and sphincter exercises may have a therapeutic effect, but this is not certain. Larger well-designed trials are needed to enable safe conclusions.