Update of tests of colon and rectal structure and function

This review deals with the indications, methods, strengths, and limitations of anorectal testing in clinical practice. In chronic constipation, anal manometry and a rectal balloon expulsion test, occasionally supplemented by defecography, are useful to identify a functional defecatory disorder, because symptoms may respond to pelvic floor retraining. In patients with fecal incontinence, diagnostic testing complements the clinical assessment for evaluating the pathophysiology and guiding management. Manometry measures anal resting and squeeze pressures, which predominantly reflect internal and external anal sphincter function, respectively. Defecation may be indirectly assessed by measuring the recto-anal pressure gradient during straining and by the rectal balloon expulsion test. Endoanal ultrasound and magnetic resonance imaging (MRI) can identify anal sphincter structural pathology, which may be clinically occult, and/or amenable to surgical repair. Only MRI can identify external sphincter atrophy, whereas ultrasound is more sensitive for internal sphincter imaging. By characterizing rectal evacuation and puborectalis contraction, barium defecography may demonstrate an evacuation disorder, excessive perineal descent or a rectocele. Dynamic MRI can provide similar information and also image the bladder and genital organs without radiation exposure. Because the measurement of pudendal nerve latencies suffers from several limitations, anal sphincter electromyography is recommended when neurogenic sphincter weakness is suspected.     

Phenotypic variation in functional disorders of defecation

BACKGROUND & AIMS: Although obstructed defecation is generally attributed to pelvic floor dyssynergia, clinical observations suggest a wider spectrum of anorectal disturbances. Our aim was to characterize phenotypic variability in constipated patients by anorectal assessments. METHODS: Anal pressures, rectal balloon expulsion, rectal sensation, and pelvic floor structure (by endoanal magnetic resonance imaging) and motion (by dynamic magnetic resonance imaging) were assessed in 52 constipated women and 41 age-matched asymptomatic women. Phenotypes were characterized in patients by principal components analysis of these measurements. RESULTS: Among patients, 16 had a hypertensive anal sphincter, 41 had an abnormal rectal balloon expulsion test, and 20 had abnormal rectal sensation. Forty-nine patients (94%) had abnormal pelvic floor motion during evacuation and/or squeeze. After correcting for age and body mass index, 3 principal components explained 71% of variance between patients. These factors were weighted most strongly by perineal descent during evacuation (factor 1), anorectal location at rest (factor 2), and anal resting pressure (factor 3). Factors 1 and 3 discriminated between controls and patients. Compared with patients with normal (n = 23) or reduced (n = 18) perineal descent, patients with increased (n = 11) descent were more likely (P < or = .01) to be obese, have an anal resting pressure >90 mm Hg, and have a normal rectal balloon expulsion test result. CONCLUSIONS: These observations demonstrate that functional defecation disorders comprise a heterogeneous entity that can be subcharacterized by perineal descent during defecation, perineal location at rest, and anal resting pressure. Further studies are needed to ascertain if the phenotypes reflect differences in the natural history of these disorders.     

Radiologic evaluation of anorectal disorders

Defecation is a dynamic event, and although evacuation proctography does not simulate physiologic defecation exactly, it does provide maximal stress to the pelvic floor and image rectal emptying, both of which are required for the diagnosis of certain conditions: MR imaging studies are attractive in that no ionizing radiation is involved, but unless an evacuation study is performed, the features of anismus, trapping in a rectocele, and intussusception cannot be diagnosed. Because these are the main reasons for investigating difficult defecation, the fluoroscopic examination is the simplest and most reliable method. Endoanal ultrasound is an ideal screening examination for incontinence to show internal sphincter degeneration and tears of the internal or external sphincters. The diagnosis of external sphincter atrophy on ultrasound is not yet resolved, and this remains an important indication for endoanal MR imaging.     

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.     

A pilot assessment of whether external coil MRI is useful to assess evacuatory disorders

This study assessed the value of common surface coil mag-netic resonance imaging (MRI) in patients with evacuatory disorders including fecal incontinence and constipation. These findings were then compared with those from other standard physiological examinations and/or surgical findings. From July 1996 to June 1997, 14 consecutive patients underwent surface coil MRI for evaluation of either fecal incontinence (n=5) or constipation (n=9). In patients with incontinence we compared the findings from endoanal ultrasound (EAUS), anal MRI, and surgery regarding morphopathological findings of the internal and external anal sphincter components. In constipated patients the findings of videoprography and dynamic pelvic MRI were compared regarding the presence of rectocele, rectoanal intussusception, and sigmoidocele as well as the measurements of anorectal angle and perineal descent. The five incontinent patients were all women, with a median age of 67 years (range 43–77). EAUS revealed an anterior sphincter defect in two patients, a posterior defect in one, and normal anal sphincter images in two. Surgical findings confirmed an anterior external anal sphincter scar in two patients, an internal anal sphincter defect in one, and an anatomically normal anal sphincter in two. In one patient, although anal MRI showed posterior external anal sphincter defect, EAUS and surgery revealed normal external anal sphincter appearance. The accuracy rate between EAUS and anal MRI was only 20%, that between surgery and anal MRI 40%, and that between surgery and EAUS 80%. Thus EAUS was more accurate than anal MRI in incontinent patients. The nine constipated patients were all women, with a mean age of 59 years (range 40–78). Videoproctography revealed an anterior rectocele in six patients, rectoanal intussusception in three, and sigmoidocele in five; no abnormalities were identified in two patients. On dynamic pelvic MRI anterior rectocele was seen in three patients and sigmoidocele in two, and five studies were interpreted as normal. One of the patients underwent sigmoidectomy for sigmoidocele, and five patients were treated by biofeedback. Thus the accuracy rate of dynamic pelvic MRI against videoproctography was 60% for anterior rectocele, 40% for sigmoidocele, and zero for rectoanal intussusception. In conclusion, neither MRI for the evaluation of patients with fecal incontinence nor for the evaluation of patients with constipation added any significant information that would warrant its continued use in these patient groups. Perhaps the more widespread availability of an endoanal coil will alter this conclusion; however, at the present time we cannot routinely endorse the expense, time, or inconvenience of these MRI investigations in patients with these diagnoses. Larger prospective comparative studies are required prior to endorsing the technique. Accepted: 21 February 2000     

Functional asymmetry of pelvic floor innervation and its role in the pathogenesis of fecal incontinence

While the regular and symmetric innervation of the pelvic floor has been regarded as "established" for many years, recent data indicate that asymmetry of innervation of the sphincters may exists and may contribute to the occurrence and severity of incontinence symptoms in case of pelvic floor trauma. METHODS: A systematic review of published papers on asymmetry of sphincter innervation was performed including studies in healthy volunteers and patients with incontinence. 234 consecutive patients with fecal incontinence were investigated by means of side-separated mass surface EMG from the left and right side anal canal, these data were correlated to clinical and anamnestic findings. RESULTS: The literature survey indicates that asymmetry of sphincter innervation exists in a subgroup of healthy male and female volunteers, and may be a risk factor to become incontinent in case of trauma. Patients with incontinence in whom asymmetry of sphincter innervation could be shown more frequently reported a history of pelvic floor trauma during childbirth. Childbirth per se but not the number of deliveries predicted sphincter asymmetry. Asymmetrically innervated sphincters show a compromised sphincter function in routine anorectal manometry. CONCLUSION: Assessment of sphincter innervation asymmetry may be of value in clinical routine testing of patients with incontinence. However, a new technology is needed to replace mass surface EMG by multi-electrode arrays on a sphincter probe. This is one of the goals of the EU-sponsored research project OASIS.     

Descending perineum syndrome: audit of clinical and laboratory features and outcome of pelvic floor retraining

Objective: Our aim was to retrospectively analyze the Mayo Clinic experience of descending perineum syndrome from 1987–1997. Methods: Clinical records were abstracted for demographic features, risk factors, results of anorectal and defecation tests, and a mailed questionnaire evaluated outcome and current symptoms. Results: All results are mean ± SD. Clinically, 39 patients (38 women, one man), mean age 53 ± 14 yr, presented with constipation (97%), incomplete rectal evacuation (92%), excessive straining (97%), digital rectal evacuation (38%), and fecal incontinence (15%). Laboratory tests showed anal sphincter resting pressure was 54 ± 26 mm Hg, and squeeze pressure was 96 ± 35 mm Hg; expulsion from the rectum of a 50-ml balloon required > 200 g added weight in 27%; perineal descent was 4.4 ± 1 cm (normal < 4 cm) by scintigraphy. Scintigraphic evacuation, rectoanal angle change during defecation, and perineal descent were abnormal in 23%, 57%, and 78% of the patients, respectively. Associated features included female gender (96%), multiparity with vaginal delivery (55%), hysterectomy or cystocele/rectocele repair (74%). On follow-up, 64% responded; 17 of these 25 responders underwent pelvic floor retraining. At 2-yr median follow-up (range, 1–6 yr), 12 still experienced constipation or excessive straining; their perineal descent was greater than in patients who responded to retraining (   p = 0.005  ). Conclusions: Descending perineum syndrome is identifiable by clinical history and examination, and the most prevalent abnormality on testing is perineal descent > 4 cm; rectal balloon expulsion is an insensitive screening test for descending perineum syndrome. Pelvic floor retraining is a suboptimal treatment for this chronic disorder of rectal evacuation; the extent of perineal descent appears to be a useful predictor of response to retraining.     

Is there a role for concomitant pelvic floor repair in patients with sphincter defects in the treatment of fecal incontinence?

BACKGROUND AND AIMS: More than half of all patients who undergo overlapping anal sphincter repair for fecal incontinence develop recurrent symptoms. Many have associated pelvic floor disorders that are not surgically addressed during sphincter repair. We evaluate the outcomes of combined overlapping anal sphincteroplasty and pelvic floor repair (PFR) vs. anterior sphincteroplasty alone in patients with concomitant sphincter and pelvic floor defects. PATIENTS AND METHODS: We reviewed all patients with concomitant defects who underwent surgery between February 1998 and August 2001. Patients were assessed preoperatively by anorectal manometry, pudendal nerve terminal motor latency, and endoanal ultrasound. The degree of continence was assessed both preoperatively and postoperatively using the Cleveland Clinic Florida fecal incontinence score. Postoperative success was defined as a score of 相似文献   

Translabial ultrasound in the assessment of pelvic floor and anorectal function in women with defecatory disorders

This article shows how modern ultrasound imaging can contribute to the investigation of patients with posterior vaginal wall prolapse, obstructed defecation, fecal incontinence and rectal intussusception/prolapse, conditions that should be similarly relevant and of interest to colorectal surgeons, gastroenterologists and gynecologists. Translabial/perineal ultrasound, a simple, universally available technique, may serve as a first-line diagnostic tool in women with posterior compartment prolapse and/or symptoms of obstructed defecation, largely replacing defecation proctography and magnetic resonance proctography. This has advantages for healthcare systems, since sonographic imaging is less expensive, non-invasive, less time-consuming and does not involve radiation exposure. However, there is a substantial need for teaching that remains unmet to date. This article illustrates in details the technique of translabial ultrasonography adopted by our unit and reviews the literature supporting this method of assessing pelvic floor and anorectal function in women with defecatory disorders.     

Female pelvic floor dysfunction--an imaging perspective

Female pelvic floor dysfunction encompasses a range of morbidities, including urinary incontinence, female pelvic organ prolapse, anal incontinence and obstructed defecation. Patients often present with symptoms covered by several specialties including gastroenterology, colorectal surgery, urology and gynecology. Imaging can therefore bring clinicians from multiple specialties together by revealing that we frequently deal with different aspects of one underlying problem or pathophysiological process. This article provides an interdisciplinary imaging perspective on the pelvic floor. Modern pelvic floor imaging comprises defecation proctography, translabial and endorectal ultrasound, and static and dynamic MRI. This Perspectives focuses on the potential use of translabial ultrasound, including 3D and 4D applications, for diagnosis of pelvic floor disorders. Over the next decade, pelvic floor imaging will most likely be integrated into mainstream diagnostics in obstetrics and gynecology and colorectal surgery. Using imaging to facilitate communication between different specialties has the potential to greatly improve the multidisciplinary management of complex pelvic floor disorders.     

Usefulness of anorectal and endovaginal 3D ultrasound in the evaluation of sphincter and pubovisceral muscle defects using a new scoring system in women with fecal incontinence after vaginal delivery

Purpose

This study aims to evaluate pubovisceral muscle and anal sphincter defects in women with previous vaginal delivery and fecal incontinence and to correlate the findings with the severity of symptoms using the combined anorectal and endovaginal 3D ultrasonography with a new ultrasound scoring system.

Methods

Consecutive female patients with previous vaginal delivery and fecal incontinence symptoms were screened. Fecal incontinence was assessed with the Cleveland Clinic Florida fecal incontinence scale, and the extent of defects was assessed by an ultrasound score based on results of anorectal and endovaginal 3D ultrasound. Fecal incontinence was assessed with the Cleveland Clinic Florida fecal incontinence scale.

Results

Of 84 women with previous vaginal delivery and fecal incontinence, 21 (25%) had intact pubovisceral muscles and anal sphincters; 63 (75%) had a pubovisceral muscle or anal sphincter defect, or both. Twenty-eight (33%) had a pubovisceral muscle defect [23% with an external anal sphincter (EAS) defect or combined EAS/internal anal sphincter defects; 11% with intact anal sphincters]. Thirty-five (42%) had intact pubovisceral muscles and an anal sphincter defect. Compared with women with intact pubovisceral muscles/anal sphincter defects, patients with pubovisceral muscle defects had significantly higher incontinence scores and significantly higher ultrasound scores indicating more extensive defects. Incontinence symptoms correlated positively with the ultrasound score, measurements of sphincter defects, and area of the levator hiatus.

Conclusions

Evaluation of both pubovisceral muscles and anal sphincters is important to identify defects and determine treatment for women with fecal incontinence after vaginal delivery. The severity of fecal incontinence symptoms is significantly related to the extent of defects of the pubovisceral muscles and anal sphincters.

     

Endoanal ultrasonography in fecal incontinence: Current and future perspectives

Fecal incontinence has a profound impact in a patient’s life, impairing quality of life and carrying a substantial economic burden due to health costs. It is an underdiagnosed condition because many affected patients are reluctant to report it and also clinicians are usually not alert to it. Patient evaluation with a detailed clinical history and examination is very important to indicate the type of injury that is present. Endoanal ultrasonography is currently the gold standard for sphincter evaluation in fecal incontinence and is a simple, well-tolerated and non-expensive technique. Most studies revealed 100% sensitivity in identifying sphincter defect. It is better than endoanal magnetic resonance imaging for internal anal sphincter defects, equivalent for the diagnosis of external anal sphincter defects, but with a lower capacity for assessment of atrophy of this sphincter. The most common cause of fecal incontinence is anal sphincter injury related to obstetric trauma. Only a small percentage of women are diagnosed with sphincter tears immediately after vaginal delivery, but endoanal ultrasonography shows that one third of these women have occult sphincter defects. Furthermore, in patients submitted to primary repair of these tears, ultrasound revealed a high frequency of persistent sphincter defects after surgery. Three-dimensional endoanal ultrasonography is currently largely used and accepted for sphincter evaluation in fecal incontinence, improving diagnostic accuracy and our knowledge of physiologic and pathological sphincters alterations. Conversely, there is currently no evidence to support the use of elastography in fecal incontinence evaluation.     

Impact of pregnancy and parturition on the anal sphincters and pelvic floor

Incontinence and defecatory difficulties are commonly reported among women and are often ascribed to traumas sustained during childbirth. Specifically, injuries to the anal sphincters (tears) and conformational changes in the various structures that comprise the pelvic floor (prolapse and perineal descent) have been considered as important contributors to the development of anal incontinence, or difficult defaecation (straining, incomplete evacuation), in later life. An understanding of both the effects of pregnancy and parturition on these structures and the natural history of any traumas sustained are, therefore, of key importance. Unfortunately, the literature on these issues, though vast, is far from complete. While it is evident that pregnancy, per se, imposes changes, primarily through hormonal influences, on colonic, ano-rectal and pelvic floor physiology, the long-term impact of such effects is far from clear. Risk factors for the occurrence of significant, though often occult, anal sphincter injuries during birth have been identified and the role of these tears in the etiology of post-partum incontinence has been well delineated. In contrast, the contribution of such intra-partum events to the later onset of incontinence is far from clear and may well have been over-estimated.     

The Utility of Pudendal Nerve Terminal Motor Latencies in Idiopathic Incontinence

Purpose Pudendal nerve terminal motor latency testing has been used to test for pudendal neuropathy, but its value remains controversial. We sought to clarify the relationship of pudendal nerve terminal motor latency to sphincter pressure and level of continence in a cohort of patients with intact anal sphincters and normal pelvic floor anatomy. Methods We reviewed 1,404 consecutive patients who were evaluated at our pelvic floor laboratory for fecal incontinence. From this group, 83 patients had intact anal sphincters on ultrasound and did not have internal or external rectal prolapse during defecography. These patients were evaluated by pudendal nerve terminal motor latency testing, a standardized questionnaire, and anorectal manometry, which measured resting and squeeze anal pressures. Incontinence scores were calculated by using the American Medical Systems Fecal Incontinence Score. Values were compared by using the Fisher’s exact test and Wilcoxon’s rank-sum test; and significance was assigned at the P < 0.05 level. Results 1) Using a 2.2-ms threshold, 28 percent of patients had prolonged pudendal nerve terminal motor latency unilaterally and 12 percent bilaterally. 2) At a 2.4-ms threshold, 18 percent of patients had prolonged pudendal nerve terminal motor latency unilaterally and 8 percent bilaterally. 3) Bilaterally prolonged pudendal nerve terminal motor latency was significantly associated with decreased maximum mean resting pressure and increased Fecal Incontinence Score, but not decreased maximum mean squeeze pressure, at both 2.2-ms and 2.4-ms thresholds. 4) Unilaterally prolonged pudendal nerve terminal motor latency was not associated with maximum mean resting pressure, maximum mean squeeze pressure, or fecal incontinence score at either threshold. Conclusions The majority of incontinent patients with intact sphincters have normal pudendal nerve terminal motor latency. Bilaterally but not unilaterally prolonged pudendal nerve terminal motor latency is associated with poorer function and physiology in the incontinent patient with an intact sphincter. Presented at the meeting of The American Society of Colon and Rectal Surgeons, Dallas, Texas, May 8 to 13, 2004. Reprints are not available.     

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

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

Anal vector volume analysis: an effective tool in the management of pelvic floor disorders

Introduction  

Different trials have investigated the role of conventional anal manometry in the diagnosis of pelvic floor disorders. The aim of the present study is to define the role and the effectiveness of vector anal manometry and vector asymmetry index scoring in the assessment of pelvic floor disorders i.e. fecal incontinence and obstructed defecation.     

Defecographic disorders in anal incontinent women: relation to symptoms and anal endosonographic patterns

OBJECTIVE: The need for a defecography in incontinent women is still debatable. We prospectively evaluated the prevalence of defecographic abnormalities in incontinent women in order to determine whether any symptom or endosonographic findings could be associated with a particular defecographic pattern. MATERIAL AND METHODS: Fifty incontinent women (aged 30-87 years) underwent defecography and anal endosonography to look for pelvic floor descent, rectocele, intussusception, enterocele and the presence of anal sphincter defects. Other symptoms, i.e. straining at stools and pelvic pressure, were recorded. RESULTS: Twenty-five cases of external sphincter defect (12 associated with an internal defect) and 4 cases of isolated internal defect were identified. Defecography identified 25 patients with perineal descent at rest, 28 with perineal descent at straining, 30 with rectocele, 30 with intussusception and 14 with enterocele. Three defecographies were normal. In the 29 women with sphincter defects, the prevalence of defecographic abnormalities did not differ from that observed in the 21 women without sphincter defects. In women complaining of straining at stools (n=26) or idiopathic pelvic pressure (n=32), the prevalence of defecographic abnormalities did not differ from that observed in women who did not have these symptoms. CONCLUSIONS: The prevalence of pelvic floor disorders in incontinent women was similar whether associated symptoms or anal sphincter defects were present or not. When defecography has to be performed to investigate female anal incontinence, neither clinical nor endosonographic features can predict a higher diagnostic efficiency.     

Role of manometry, defecography and anal endosonography in the evaluation of colorectal disorders.

OBJECTIVE: altered motility or anatomy of the rectum, anus and perineal floor may lead to symptoms which are unresponsive to routine therapeutic approaches. These disturbances usually lead to constipation, fecal incontinence, or both. Different tests and techniques for evaluating anorectal and perineal disorders, developed in the last two decades, make a better understanding of these disorders possible. This study was designed to evaluate the diagnostic benefits of combining manometry, defecography and anal endosonography in the assessment of patients with anorectal disorders. METHODS: twenty-five children with constipation (with or without soiling), incontinence and/or prolapse underwent anal manometry, defecography and anal endosonography. Group A consisted of 9 children with fecal incontinence, group B consisted of 10 children with constipation with soiling, and group C comprised 6 children with constipation without soiling. RESULTS: in group A resting incontinence was associated with a hypotonic external sphincter in 4 out of 9 patients, 2 of whom had internal anal sphincter thinning. In group B resting incontinence was associated with a hypotonic external sphincter in 8 out of 10 patients, 6 of whom had internal anal sphincter thinning. In group C these associations were not seen in any of the patients. CONCLUSIONS: barium enema is not sufficient for an accurate diagnosis of anorectal disorders. No single test is capable of revealing the type of disease. Anal manometry, defecography and endosonography are complementary procedures in the assessment of this group of disorders. This new approach will improve our knowledge of the pathogenesis of these disorders in children. However, further studies are needed to obtain conclusive evidence.     

Preliminary experience in management of fecal incontinence caused by internal anal sphincter injury

PURPOSE: Isolated injuries of the internal anal sphincter can cause fecal incontinence. With the advent of ultrasound, which accurately delineates the anatomy of the anal sphincters, internal sphincter injuries can be diagnosed more precisely. The purpose of this study was to evaluate the outcome of direct repair of isolated internal anal sphincter defects. METHODS: Eight patients (6 males; median age, 37 years) with clinically and sonographically proved internal anal sphincter defects were the subject of this study. Patients had different degrees of incontinence that failed to respond to medical treatment. All patients had their sphincters repaired by direct apposition using coated Vicryl® 2-0 stitches. A strict postoperative regime that avoided stretch of the sphincter for one month was adopted. RESULTS: At a median follow-up period of 15 months, continence improved in all patients, and two achieved full continence. None of the patients wore pads. Mean continence score improved significantly from 4 to 12 and 11 at 6 and 12 postoperative months, respectively (P<0.0001, pairedt-test). CONCLUSION: Despite the limited number of patients and the short follow-up, the preliminary results of repair of isolated internal sphincter defects are satisfactory.     

Treatment of fecal incontinence

Opinion statement Fecal incontinence is a symptom of many disorders that can affect the nerves and muscles controlling defecation; it is not just due to exceptionally voluminous diarrhea. Underlying problems should be identified and treated, because that may improve incontinence. If treatment of the underlying problem does not correct incontinence, several approaches can be employed successfully. General approaches include stimulation of defecation at intervals to empty the rectum under supervised conditions; treatment of diarrhea, if present; addressing coexisting psychologic problems, such as depression; use of continence aids, such as adult diapers; and perineal skin care to prevent skin breakdown. Drug therapy includes use of constipating drugs, such as loperamide or diphenoxylate, that can impede the gastrocolic reflex, thereby limiting rectal filling and the likelihood of incontinence. Biofeedback training is useful in patients with some ability to sense rectal distention and to contract the external anal sphincter; instrumental learning using manometric or electromyographic biofeedback can be used to reinforce the rectoanal contractile response to rectal distention. Improvement in continence has been noted in up to 70% of suitable candidates with a single biofeedback training session. Patients with external anal sphincter disruption due to childbirth injury or other trauma may benefit from direct external anal sphincter repair (sphincteroplasty). In others, tightening up the anal canal by encirclement with nonabsorbable mesh (Thiersch procedure), perianal injection of fat, collagen, or synthetic gel, or radiofrequency electrical energy (Stretta procedure) may provide some palliation. Creation of a new sphincter mechanism by muscle transposition and encirclement of the anal canal is another approach that has been improved by use of electrical stimulators to keep the neosphincter contracted. Artificial anal sphincters patterned after artificial urinary sphincters have met with some success, but local infection remains problematic. When all else fails, fecal diversion (ileostomy, colostomy) can be effective in rehabilitating patients.