Anal Sphincter Damage After Vaginal Delivery

PURPOSE: This study was designed to assess the relationship of anal endosonography and manometry to anorectal complaints in the evaluation of females a long time after vaginal delivery complicated by anal sphincter damage. METHODS: Thirty-four patients with anal sphincter damage after delivery, 22 with and 12 without anorectal complaints, and 12 controls without anorectal complaints underwent anal endosonography, manometry, and rectal sensitivity testing. Complaints were assessed by questionnaire, with a median follow-up of 19 years. RESULTS: Median maximum anal resting pressures were significantly lower in patients with anal sphincter damage with complaints (31 mmHg) than in controls (52 mmHg; P < 0.001). Median maximum anal squeeze pressures were significantly lower in patients with (55 mmHg) and without (69 mmHg) complaints than in controls (112 mmHg; P < 0.001 for both). Maximum anal resting pressures were significantly lower in patients with anorectal complaints after anal sphincter damage than in patients without complaints (P = 0.02). Results of anal manometry showed a large overlap between all groups. Rectal sensitivity showed no significant differences between the three groups. Persisting sphincter defects, shown by anal endosonography, were significantly more present in patients with anal sphincter damage after delivery with (86 percent) and without (67 percent) complaints than in controls (8 percent; P < 0.001 and P < 0.01, respectively). No differences in the number of echocardiographically proven sphincter defects were found between patients with or without anorectal complaints after anal sphincter damage CONCLUSIONS: Echographically proven sphincter defects are strongly associated with a history of anal sphincter damage during delivery. Sphincter defects are present in the majority of patients with anorectal complaints. Anal manometry provides little additional therapeutic information when performed after anal endosonography in patients with anorectal complaints after anal sphincter damage during delivery.     

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.     

Endoanal ultrasound assessment of sphincter defects and thinning – Correlation with anal manometry

Background and study aimsThis study aims to determine if anal sphincter defects/thinning observed at endoanal ultrasound correlates with anal pressures recorded at anal manometry.Patients and methodsA total of 30 consecutive patients with history suggestive of anal sphincter pathology underwent anal endosonography with documentation of internal and external sphincter defects/thinning. The same patients underwent anal manometry with documentation of maximum resting and maximum squeeze pressures. Patients with a sphincter defect (SD) were compared to patients without a sphincter defect (NSD) and both groups were compared with respect to findings in manometry. The Mann–Whitney U test was used for statistical analysis. This study was approved by the Institutional Ethics Committee.ResultsA statistically significant correlation was found between decreased maximal resting pressure and decreased internal anal sphincter (IAS) thickness or an IAS defect. The correlation between MSP and external sphincter pathology was significantly less consistent in our study.ConclusionOur study showed a statistically significant correlation between maximum resting pressure and observation of internal sphincter defects at endoanal ultrasound. The patients with documented internal sphincter defects have significantly reduced maximum resting pressures. There was however, no correlation between external sphincter defects and decrease in maximum squeeze pressure as has been observed in other studies. Until a manometry cut-off can be set to discriminate between the absence and presence of defects, both manometry and ultrasound should be offered to patients with history suggesting anal sphincter pathology.     

Anal inspection and digital rectal examination compared to anorectal physiology tests and endoanal ultrasonography in evaluating fecal incontinence

Background Anal inspection and digital rectal examination are routinely performed in fecal incontinent patients but it is not clear to what extent they contribute to the diagnostic work-up. We examined if and how findings of anal inspection and rectal examination are associated with anorectal function tests and endoanal ultrasonography. Methods A cohort of fecal incontinent patients (n=312, 90% females; mean age 59) prospectively underwent anal inspection and rectal examination. Findings were compared with results of anorectal function tests and endoanal ultrasonography. Results Absent, decreased and normal resting and squeeze pressures at rectal examination correlated to some extent with mean (±SD) manometric findings: mean resting pressure 41.3 (±20), 43.8 (±20) and 61.6 (±23) Hg (p<0.001); incremental squeeze pressure 20.6 (±20), 38.4 (±31) and 62.4 (±34) Hg (p<0.001). External anal sphincter defects at rectal examination were confirmed with endoanal ultrasonography for defects <90 degrees in 36% (37/103); for defects between 90-150 degrees in 61% (20/33); for defects between 150-270 degrees in 100% (6/6). Patients with anal scar tissue at anal inspection had lower incremental squeeze pressures (p=0.04); patients with a gaping anus had lower resting pressures (p=0.013) at anorectal manometry. All other findings were not related to any anorectal function test or endoanal ultrasonography. Conclusions Anal inspection and digital rectal examination can give accurate information about internal and external anal sphincter function but are inaccurate for determining external anal sphincter defects <90 degrees. Therefore, a sufficient diagnostic work-up should comprise at least rectal examination, anal inspection and endoanal ultrasonography.     

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.     

Endoanal Ultrasound Compared to Anorectal Manometry for the Evaluation of Fecal Incontinence: A Study of the Effect These Tests Have on Clinical Outcome

Tests for evaluating incontinence include endoanal ultrasound (EUS) and anorectal manometry. We hypothesized that EUS would be superior to anorectal manometry in identifying the subset of patients with surgically correctable sphincter defects leading to an improvement in clinical outcome in these patients. The purpose of this study was to compare these 2 techniques to determine which is more predictive of outcome for fecal incontinence. Thirty-five unselected patients with fecal incontinence were prospectively studied with EUS and anorectal manometry to evaluate the internal anal sphincter (IAS) and external anal sphincter (EAS). EUS was performed with Olympus GFUM20 echoendoscope and a hypoechoic defect in the EAS or IAS was considered a positive test. Anorectal manometry was performed with a standard water-perfused catheter system. A peak voluntary squeeze pressure of < 60 mm Hg in women and 120 mm Hg in men was considered a positive test. All patients were administered the Cleveland Clinic Continence Grading Scale at baseline and at follow-up. Improvement in fecal control was defined as a 25% or greater decrease in continence score. EUS versus manometry were compared with subsequent surgical treatment and outcome. P-values were calculated using Fisher's exact test. Patients (n = 32; 31 females) were followed for a mean 25 months (range 13–46). Sixteen patients had improved symptoms (50%). There was no correlation between EUS or anorectal manometry sphincter findings and outcome. Seven of 14 (50%) patients who subsequently underwent surgery versus 9 of 18 (50%) without surgery improved (P = .578). In long-term follow-up, approximately half of patients improve regardless of the results of EUS or anorectal manometry, or whether surgery is performed. Supported in part by a Glaxo-Wellcome Institute for Digestive Health Award.     

Hot or cold in anal pain?

In 26 volunteers without anorectal complaints, and in 31 patients with anorectal problems such as hemorrhoidal disease, anal fissure, and proctalgia fugax, baseline resting anal canal pressures were recorded manometrically for 5 minutes at room temperature (23° C). In 16 volunteers (Group A) and 21 patients (group B) anorectal manometry was then performed while the anus was immersed in water at varying temperatures (5° C, 23° C, and 40° C). In ten volunteers (Group A′) and ten patients (Group B′) resting pressures were recorded for an additional 30 minutes following immersion for 5 minutes at 40° C. In all subjects (at leastP<0.01), resting anal canal pressures diminished significantly from baseline after immersion at 40° C, but remained unchanged in all subjects after immersion at 5° C and 23° C. In Group A′, anal canal pressures remained significantly reduced for 15 minutes (P<0.02). In Group B′, significant reduction in resting pressure lasted 30 minutes (P<0.02). Wet heat applied to the anal sphincter apparatus significantly and reproducibly decreased resting anal canal pressures over time, and therefore was likely to benefit patients after anorectal operations and those with anorectal pain.     

Normal variation in anorectal manometry

A study was performed to define the normal range of values for anorectal manometry. Normal volunteers were divided according to gender and parity. There were 20 males, 21 nulliparous females, and 18 multiparous females among the 59 subjects. Anorectal manometry using a radial eight-port catheter was performed during resting and squeezing maneuvers of the anal sphincter. Computerized data analysis and three-dimensional imaging were used to calculate sphincter length at rest and squeeze, mean maximum resting and squeeze pressures, and vector symmetry index. The sphincter length at rest and with squeezing in males was significantly greater compared with the two female groups (P <0.007). Mean maximum squeeze pressures were also significantly elevated in the male group compared with the female groups (P=0).Mean maximum resting pressures were significantly higher in nulliparous women than in multiparous women (P=0.04).However, no difference in resting pressures was found between males and nulliparous females. A comparison of the symmetry of the anal canal revealed no differences among the three groups. Ranges for normal anorectal manometry are definable. Normal ranges are distinct for subgroups of patients, particularly with regard to gender and parity. Patients must be compared with their normal subgroups to correctly identify manometric abnormalities.     

Diagnosing anal sphincter injury with transanal ultrasound and manometry

PURPOSE: This study was undertaken to evaluate how well anorectal manometry and transanal ultrasonography diagnose anal sphincter injury. METHODS: Anorectal manometry and transanal ultrasonography were performed in 20 asymptomatic nulliparous women and 20 asymptomatic parous women, and the results were compared with those obtained in 31 incontinent women who subsequently underwent sphincteroplasty and, thus, had operatively verified anal sphincter injury. By using computerized manometry analysis, mean maximum resting and squeeze pressures, sphincter length, and vector symmetry were determined in all women. All transanal ultrasounds were interpreted blinded as to the patient's history, physical examination, and manometry results. RESULTS: Manometric resting and squeeze pressures were significantly higher in the asymptomatic nulliparous women than in the asymptomatic parous women, and both groups had significantly higher pressures than the incontinent women ( P <0.001). Anal sphincter length and vector symmetry index were significantly decreased in incontinent women compared with asymptomatic women ( P <0.01). Decreased resting and squeeze pressures suggestive of possible sphincter injury were found in 90 percent of incontinent women with known anal sphincter injury. Decreased anal sphincter length and vector symmetry were found in only 42 percent of women with known anal sphincter injury. Transanal ultrasound was able to identify 100 percent of the known sphincter injuries but also falsely diagnosed injury in 10 percent of the asymptomatic nulliparous women with intact anal sphincters. False identification of sphincter injury increased when transanal ultrasound scanning was performed proximal to the distal 1.5 cm of the anal canal. CONCLUSION: Although nonspecific, decreased resting and squeeze pressures were found in 90 percent of patients with anal sphincter injury. Decreased anal sphincter length or vector symmetry index were present in only 42 percent of patients with known sphincter injury. When limited to the distal 1.5 cm of the anal canal, transanal ultrasound identified all known sphincter injuries but falsely identified injury in 10 percent of women with intact anal sphincters. Transanal ultrasound in combination with decreased anal pressures correctly identified all intact sphincters and 90 percent of known anal sphincter injuries.Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994. Winner of the New England Society of Colon and Rectal Surgeons Award.     

Postdelivery anal function in primiparous females

PURPOSE: A study was performed to evaluate the early morphologic and functional consequences of vaginal delivery on the anal sphincter in primiparous females. METHODS: Among a cohort of 197 primiparous females who agreed to participate in a clinical evaluation of fecal incontinence and in a transanal ultrasound examination 12 weeks after delivery, 52 also underwent anal manometry using a radial six-port catheter, of whom 10 were asymptomatic and had a normal sphincter at ultrasound and the remaining 42 had clinical signs of anal incontinence or ultrasonographic defects of the anal sphincter or both. Anal sphincter pressures and asymmetry index were analyzed at rest and during voluntary squeeze. Manometric and ultrasound results were compared, together with clinical symptoms. RESULTS: Fourteen patients with clinical signs of anal incontinence had lower resting and squeeze anal pressures than continent patients (P<0.05), but similar anal asymmetry indexes. Patients with incontinence and an anal defect had the lowest resting and squeeze anal pressures (P<0.05). Forceps assistance to delivery was not associated with a higher frequency of anal sphincter lesions. Resting and squeeze anal pressures were lower in the forceps group (P<0.005), but anal asymmetry indexes were similar. Finally, manometric results were identical in the presence or absence of anal sphincter endosonographic defects. CONCLUSIONS: Anal sphincter defects are frequent after the first vaginal delivery, but are not always associated with functional or clinical abnormalities. Resting and squeeze anal pressures were significantly decreased in patients with incontinence and an anal defect and after forceps-assisted deliveries. Anal asymmetry index was not found useful in this population of young primiparous females.Presented in part at the Journées Francophones de Pathologie Digestive, Paris, France, March 21 to 25, 1998.     

Anal endosonography and manometry

PURPOSE: Correlations between anal sphincter function as assessed by anorectal manometry and anal sphincter anatomy measured by endoluminal ultrasound have been reported in the literature both for patients and for healthy individuals but have not been confirmed by other authors. METHODS: For a larger series of patients (152 consecutive patients, mean age 54.1±15.5 years; female:male ratio, 11141) with anorectal dysfunctions such as incontinence (n=92), constipation (n=37), and other symptoms (n=23), diagnostic work-up included conventional multilumen anorectal manometry to evaluate internal sphincter pressure at rest, maximum external sphincter squeeze pressure during contraction, and endoanal sonography to determine anal sphincter integrity and to measure dorsal, left lateral, and right lateral diameter of the internal anal sphincter (IAS) and external anal sphincter (EAS) muscles. RESULTS: Maximum squeeze pressure was significantly correlated to muscle thickness of the EAS(P =0.001). No association was found between resting pressure and IAS diameter. Women had significantly lower resting and squeeze pressures than men(P =0.008 and P =0.003, respectively), but age-related changes of function were only found for resting pressure. Endosonographic values of IAS and EAS did not differ between genders but were significantly correlated with age(P =0.008 and P =0.02, respectively). Because all correlations were rather weak, they only can explain a small portion of data variance. CONCLUSION: Anal manometry and anal ultrasound, therefore, are of complementary value and are both indicated in adequate clinical problems.Supported by a grant from Deutsche Forschungsgemeinschaft, En 50/10, Bonn, Germany.     

Effects of Caffeine on Anorectal Manometric Findings

Purpose  This study was designed to evaluate the effects of caffeine on anorectal function by anorectal manometry. Methods  Ten healthy subjects were studied. They drank 200 ml of water and later 200 ml of a solution that contained caffeine 3.5 mg/kg body weight. The anorectal manometric study was divided into three periods: basal, water, and caffeine; each period lasted 45 minutes. Results  After the ingestion of water, the basal anal sphincter pressure showed no change during the 45-minute recording, whereas after caffeine consumption the basal anal sphincter pressure increased at 10 minutes (P = 0.047) and 15 minutes (P = 0.037). The average basal anal sphincter pressure throughout the 45 minutes was significantly higher after caffeine ingestion than after water (P = 0.013). After caffeine intake, the maximum squeeze pressure increased significantly (P = 0.017) compared with the basal period. Both water and caffeine consumption caused a decrease in the rectal sensory threshold for the desire to defecate. Conclusions  Caffeine 3.5 mg/kg body weight in 200 ml of water resulted in stronger anal sphincter contractions both at basal period and during voluntary squeeze. The sensory threshold was also decreased, leading to an earlier desire to defecate. Caffeine consumption may result in an earlier desire to defecate, leading to defecation if the anal sphincter can relax voluntarily.     

Ultrasonographic patterns in patients with obstructed defaecation

Background Anal ultrasound is helpful in assessing organic anorectal lesions, but its role in functional disease is still questionable. The purpose of the present study is to assess anal–vaginal–dynamic perineal ultrasonographic findings in patients with obstructed defecation (OD) and healthy controls. Materials and methods Ninety-two consecutive patients (77 women; mean age 51 years; range 21–71) with symptoms of OD were retrospectively evaluated. All patients underwent digital exploration, endoanal and endovaginal ultrasound (US) with rotating probe. Forty-one patients underwent dynamic perineal US with linear probe. Anal manometry and defaecography were performed in 73 and 43 patients, respectively. Ultrasonographic findings of 92 patients with symptoms of OD were compared to 22 healthy controls. Anismus was defined on US when the difference in millimetres between the distance of the inner edge of the puborectalis muscle posteriorly and the probe at rest and on straining was less then 5 mm. Sensitivity and specificity were calculated by assuming defaecography as the gold standard for intussusception and rectocele and proctoscopy for rectal internal mucosal prolapse. Since no gold standard for the diagnosis of anismus was available in the literature, the agreement between anal US and all other diagnostic procedures was evaluated. Results The incidence of anismus resulted significantly higher (P < 0.05) in OD patients than healthy controls on anal (48 vs 22%), vaginal (44 vs 21%), and dynamic perineal US (53 vs 22%). A significantly higher incidence of rectal internal mucosal prolapse was observed in OD patients when compared to healthy controls on both anal (61.9 vs 13.6%, P < 0.0001) and dynamic perineal US (51.2 vs.9% P = 0.001). For the diagnosis of rectal internal mucosal prolapse, anal US had a 100% sensitivity and specificity. For diagnosis of rectal intussusception, anal US had an 83.3% sensitivity and 100% specificity and perineal US had a 66.6% sensitivity and 100% specificity. In the diagnosis of anismus, anal ultrasonography resulted in agreement with perineal and vaginal US, manometry, defaecography, and digital exam (P < 0.05). Other lesions detected by US in patients with OD include solitary rectal ulcer, rectocele and enterocele. Damage of internal and/or external sphincter was diagnosed at anal US in 19/92 (20%) patients, all continent and with normal manometric values. Conclusion Anal, vaginal and dynamic perineal ultrasonography can diagnose or confirm many of the abnormalities seen in patients with OD. The value of the information obtained by this non-invasive test and its role in the diagnostic algorithm of OD is yet to be defined.     

Contribution of Posture to Anorectal Manometric Measurements: Are the Measurements in Left-Lateral Position Physiologic?

Purpose Anorectal manometry is commonly used to investigate fecal incontinence. Traditional practice dictates that measurements are performed with the patient in the left-lateral position however, episodes of fecal incontinence usually occur in the erect position. The influence of erect posture on anorectal manometry has not been studied. Methods We examined the contribution of posture to commonly measured variables during manometry by performing assessment in the left-lateral position and the erect posture. Maximum mean resting pressure, vector volumes, and resting pressure gradient were compared. Results Complete data were available for 172 patients. Median age was 55 (interquartile range, 44–65) years. Thirty-seven (22 percent) patients were continent, and 135 (78 percent) were incontinent. Both resting pressure and vector volume increased significantly in the erect position for both continent (P = 0.008 and 0.001, respectively) and incontinent (P = 0.001 for both) patients. A significant negative correlation was seen between severity of incontinence and resting pressure in the erect posture and amount of change in maximum mean resting pressure from left-lateral to erect posture (Spearman coefficients = −0.203, −0.211, and P = 0.013, 0.017, respectively) but not with maximum mean resting pressure in the left-lateral position (Spearman coefficient = −0.119; P = 0.164). Conclusions Our study shows significant increase in measurements of manometric variables in the erect position. The increase may be related to anal cushions, which have a significant role in this position. The measurements in erect posture are better correlated with severity of incontinence and may be a more physiologic method of performing anorectal manometry. Presented at the meeting of the Association of Coloproctology of Great Britain and Ireland, Birmingham, United Kingdom, June 28 to July 1, 2004.     

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.     

Unilateral Pudendal Neuropathy is Common in Patients with Fecal Incontinence

Purpose Pudendal neuropathy and fecal incontinence frequently coexist; however, the contribution of neuropathy is unknown. The pudendal nerve innervates the external anal sphincter muscle, anal canal skin, and coordinates reflex pathways. Lateral dominance or a dominantly innervating nerve and its subsequent damage may have major implications in the etiology and treatment of fecal incontinence. This study was designed to establish the prevalence of pudendal neuropathy, in particular a unilateral one, and to examine the impact on anorectal function. Methods A total of 923 patients (745 females; mean age, 52 (range, 17–92) years) with fecal incontinence were studied using endoanal ultrasonography, anorectal manometry, rectal sensation, and pudendal nerve terminal motor latencies. Results A total of 520 patients (56 percent) demonstrated a pudendal neuropathy, which was unilateral in 38 percent (351 patients; 169 right-sided, 182 left-sided). Neuropathy, whether it was bilateral (bilateral vs. normal; 56 (range, 7–154) cm H₂O) vs. 67 (range, 5–215) cm H₂O; P < 0.01) or unilateral (unilateral vs. normal; 61 (range, 0–271) cm H₂O vs. 67 (range, 5–215) cm H₂O; P = 0.04) was associated with reduced anal resting tone. This also was seen with respect to squeeze increments (bilateral vs. normal; 34 (range, 0–207) cm H₂O vs. 52 (range, 0–378) cm H₂O; P < 0.001, unilateral vs. normal; 41 (range, 0–214) cm H₂O vs. 52 (range, 0–378) cm H₂O; P < 0.01). In those with intact sphincters, unilateral neuropathy was associated with reduced squeeze increments (unilateral vs. normal; 60 (range, 10–286) cm H₂O vs. 69 (range, 7–323) cm H₂O; P = 0.01) but no significant reduction in resting pressures. There was no association between pudendal neuropathy and abnormal rectal sensitivity. Conclusions Unilateral pudendal neuropathy is a common abnormality in individuals with fecal incontinence and is significantly associated with both attenuated resting pressures and squeeze increments. Although there are limitations in the interpretation of pudendal nerve terminal motor latencies, this study demonstrates that further exploration of the concept of lateral dominance is needed. Supported by a grant from Dunhill Medical Trust/Royal College of Surgeons. Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 3 to 7, 2006. Reprints are not available.     

Sphincter Defects Are Not Associated With Long-Term Incontinence Following Ileal Pouch-Anal Anastomosis

INTRODUCTION Frequent loose stools test the integrity of sphincter function in patients undergoing ileal pouch-anal anastomosis. The authors hypothesized that women with anal sphincter defects were more likely to experience incontinence episodes than women with intact sphincter muscles following ileal pouch-anal anastomosis.METHODS From 1996 to 1998, 42 women with a mean age of 42 (range, 22–63) years were prospectively evaluated by anorectal manometry and endoanal ultrasound before pouch surgery. Forty women underwent a stapled ileal pouch-anal anastomosis and two underwent a handsewn anastomosis. All patients considered themselves continent of stool before the procedure. A postoperative survey including the Cleveland Clinic Florida scale, Fecal Incontinence Severity Index, and Fecal Incontinence Quality of Life scale was sent to study participants.RESULTS Nineteen women with an obstetrical history had significant sphincter defects associated with significant lower mean resting pressure, mean squeeze pressure, and shorter anal canal length (3 vs. 3.7 cm, P = 0.0007). Thirty-five women (83 percent) responded resulting in a mean follow-up of 62 (range, 49-72) months. Fourteen responders (mean age, 46 years) had sphincter defects but no significant difference was found in Cleveland Clinic Florida scale, Fecal Incontinence Severity Index, or Fecal Incontinence Quality of Life scale scores when compared with those without defects.CONCLUSION Although almost all women reported episodes of seepage, marked sphincter defects associated with low anal pressures and shorter anal canal length did not affect anal function following pouch surgery. This study supports the findings that continent women with significant sphincter defects on ultrasound evaluation may be considered for restorative proctocolectomy.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, New Orleans, Louisiana, June 22 to 26, 2003.     

Diabetes Mellitus and Anal Sphincter Pressures: An Experimental Model in Rats

Purpose Symptoms of the gastrointestinal tract, frequent in patients with diabetes mellitus, which may be related to an increase in the production of free radicals, include alterations in the function of the sphincter anal musculature. Such alterations are characterized by a decrease of muscular tone associated with different degrees of fecal incontinence. This study was performed to show the alterations in the anal sphincter pressures of diabetic rats and to evaluate the role of nitric oxide and oxidative stress in this situation. Methods Male Wistar rats weighing 250 to 400 g were used. The animals were divided in two groups: control and diabetic. Diabetes was induced through intraperitoneal injection of streptozotocin and the anal pressures were gauged by anorectal manometry. Nitric oxide was evaluated through measures of nitrites and nitrates, and oxidative stress through the technique of chemoluminescence. Results There was a significant decrease in the sphincter anal pressure of diabetic animals 60 days after induction (P < 0.05). This pressure returned to basal values after administration of a nitric oxide synthase antagonist. The levels of nitrites and nitrates as well as of lipoperoxidation were significantly increased in the diabetic compared with the control group (P < 0.05). Conclusions In this study, hyperglycemia of diabetes mellitus caused an increase in the oxidative stress. Apparently the elevation of nitric oxide levels was one of the responsible factors for the decrease of anal sphincter pressures.     

A New Method of Assessing Anal Sphincter Integrity Using Inverted Vectormanometry

Purpose Vectorgraphy as an integrated mapping of radial pressure profiles of the anal canal has been used to attempt identification of pressure-related defects with doubtful reliability since vectorgraphs bear no resemblance to endoanal ultrasound scans at similar levels in the anal canal. This study aimed to devise a technique to enable vectorgraphy to be more representative of sphincter function and integrity. Methods Vectormanometry was performed in 50 patients with anorectal disorders using an Arndorfer pneumohydraulic system. “Normal” three-dimensional manometric images of each 0.5 cm of the anal sphincter were computer-generated by plotting anal pressures at rest and during squeeze radially around a central zero axis. The graphs were replotted with zero at the periphery and maximal anal pressure at the center. Both this (“inverted”) and “normal” vectorgraphs were compared with endoanal ultrasound images at similar levels, assessing both internal and external anal sphincters. Results Standard vectormanometry produced excellent pictures of pressures throughout the anal canal; the anatomy however bore no resemblance to the pictures produced by endoanal ultrasound. The inverted vectographs showed a much better correlation with endoanal ultrasound at each 0.5-mm level of the anal canal, for both squeeze pressure graphs and external sphincter correlations and for resting pressure graphs and internal sphincter correlations. Conclusions Accurate assessment of sphincter integrity is not possible when interpreting the vectormanometry graphs in the current format; however, inverted vectorgraphy gives good correlations with endoanal ultrasound and provides combined functional (pressure measurement) and anatomic (three-dimensional profile) information regarding the anal canal. Presented at the Congress of the International Society of University Colon and Rectal Surgeons, Osaka, Japan, April 14 to 18, 2002.     

Anal sphincter integrity and function influences outcome in rectovaginal fistula repair

PURPOSE: Traumatic sphincter disruption frequently is associated with a rectovaginal fistula, but the effect of a persistent sphincter defect on the outcome of rectovaginal fistula repair is poorly documented. We analyzed the outcome of rectovaginal fistula repairs based on preoperative sphincter status. PATIENTS AND METHODS: We identified 52 women who underwent 62 repairs of simple obstetrical rectovaginal fistulas between 1992 and 1995. Fourteen patients (27 percent) had preoperative endoanal ultrasound studies and 25 (48 percent) had anal manometry studies. Follow-up was by mailed questionnaire in 36 patients (69 percent) and by telephone interview in 12 (23 percent), for a total response rate of 92 percent. Median age was 30.5 (range, 18–70) years, and median follow-up was 15 (range, 0.5–123) months. Twenty-five patients (48 percent) complained of varying degrees of fecal incontinence before surgery. There were 27 endorectal advancement flaps and 35 sphincteroplasties (28 with and 8 without levatoroplasty). RESULTS: Success rates were 41 percent with endorectal advancement flaps and 80 percent with sphincteroplasties (96 percent success with and 33 percent without levatoroplasty;P=0.0001). Endorectal advancement flap was successful in 50 percent of patients with normal sphincter function but in only 33 percent of patients with abnormal sphincter function(P=not significant). For sphincteroplasties, success rates were 73vs. 84 percent for normal and abnormal sphincter function, respectively (P=not significant). Results were better after sphincteroplastiesvs. endorectal advancement flaps in patients with sphincter defects identified by endoanal ultrasound (88vs. 33 percent;P=not significant) and by manometry (86vs. 33 percent;P = not significant). Poor results correlated with prior surgery in patients undergoing endorectal advancement flaps (45 percentvs. 25 percent;P = not significant) but not sphincteroplasties (80vs. 75 percent;P = not significant). CONCLUSIONS: All patients with rectovaginal fistula should undergo preoperative evaluation for occult sphincter defects by endoanal ultrasound or anal manometry or both procedures. Local tissues are inadequate for endorectal advancement flap repairs in patients with sphincter defects and a history of previous repairs. Patients with clinical or anatomic sphincter defects should be treated by sphincteroplasty with levatoroplasty.Read at the Minnesota Surgical Society, May 3, 1996, at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996, and at the Tripartite Meeting, July 8 to 10, 1996.