Anismus in patients with normal and slow transit constipation

Randomized clinical trial: efficacy of a food supplement, TRANSITECH, on healthy individuals with mild intermittent constipation

BACKGROUND

Constipation is a common disorder in the general population and can be observed in healthy individuals. A natural product leading to an increase in bowel movements and decrease in colonic transit time (CTT), without bloating, could be useful for the patient's care.

OBJECTIVES

To investigate the effects of TRANSITECH, a food supplement composed of plants and lactic ferments, on bowel movements, CTT and bloating.

METHODS

A total of 100 healthy participants, presenting two to five stools per week, were selected and followed over a 6-day baseline period. They were randomly assigned to receive daily two tablets of TRANSITECH or placebo during 10 days. They were then followed up over 28 days after intervention. Participants daily recorded in a home questionnaire the characteristics of stools (frequency and consistency), and the importance of bloating during the preintervention period (from D-6 to D0), the intervention period (from D0 to D10) and the postintervention period (from D10 to D38). Their CTTs were also evaluated by following the propagation of radiopaque markers at D0 and D10.

RESULTS

At D10, the food supplement group showed, compared with the placebo group, higher daily stool emission (0.95±0.50, 0.70±0.20, P<0.001), softer stool consistency (2.5±0.6 vs. 3.0±0.8, P<0.001) and lower CTT (33.8±28.2 vs. 56.4±36.2 h, P=0.01). The active group also showed a sustained increase in daily stool emissions observed at D38 compared with D0 (P=0.03).

CONCLUSION

TRANSITECH is an efficient natural solution for the treatment of constipation. It increases the number of bowel movements, decreases the oroanal and segmental CTT, is well tolerated, and presents sustained effects after treatment completion.

Diagnostic testing for dyssynergic defecation in chronic constipation: meta-analysis

BACKGROUND

Dyssynergic defecation (DD) results from inadequate relaxation of the pelvic floor on attempted defecation. The prevalence of DD in patients with chronic constipation (CC) is not certain. Aims of this study are to estimate the prevalence of abnormal findings associated with DD across testing modalities in patients referred for physiological testing for CC.

METHODS

Systematic search of MEDLINE, EMBASE and PUBMED databases were conducted. We included full manuscripts reporting DD prevalence in CC, and specific findings at pelvic floor diagnostic tests. Random effects models were used to calculate pooled DD prevalences (with 95% CI) according to individual tests and specific findings.

KEY RESULTS

A total of 79 studies on 7581 CC patients were included. The median prevalence of any single abnormal finding associated with DD was 37.2%, ranging from 14.9% (95% CI 7.9-26.3) for absent opening of the anorectal angle (ARA) on defecography to 52.9% (95% CI 44.3-61.3) for a dyssynergic pattern on ultrasound. The prevalence of a dyssynergic pattern on manometry was 47.7% (95% CI 39.5-56.1). The prevalence of DD was similar across specialty and geographic area as well as when restricting to studies using Rome criteria to define constipation.

CONCLUSIONS & INFERENCES

Dyssynergic defecation is highly prevalent in CC and is commonly detected across testing modalities, type of patient referred, and geographical regions. We believe that the lower prevalence of findings associated with DD by defecography supports use of manometry and balloon expulsion testing as an initial evaluation for CC.

Early recognition of pelvic floor dyssynergia and colorectal assessment in Parkinson's disease associated with bowel dysfunction

AIM

Slow colonic transit time (CTT) and pelvic floor dyssynergia (PFD) are major contributors to constipation in patients with Parkinson's disease (PD). However, no symptom survey yet exists that effectively differentiates the contributing aetiologies. The significance of individual pelvic floor musculature behaviours and their relationship with colorectal dysmotility in constipated patients with PD are still controversial and need further clarification. We aimed to investigate how differentiated constipation-related symptoms of PD patients with constipation may identify constipation groupings and to register the pathophysiological features of the pelvic musculature.

METHOD

Our subjects undertook CTT, defaecography and the Knowles-Eccersley-Scott Symptom questionnaire. The pathological aetiologies were categorized as group 1 (slow CTT) and/or group 2 (puborectalis syndrome) and/or group 3 (pubococcygeus syndrome), in accordance with the CTT and defaecography results.

RESULTS

Constipation-related symptoms such as incomplete evacuation and defaecation difficulty yielded high post-test probabilities (81% and 88%, respectively) in groups 3 and 2, but a low post-test probability in group 1 (58%). Changes in the anorectal angle and perineum descent during straining were significantly correlated with CTT (r = 0.57 and r = 0.61, respectively) and with each other (r = 0.82).

CONCLUSION

Our findings that neural control of the puborectalis and pubococcygeus, along with colorectal peristalsis, were in a similar state of degeneration is key information that should assist physicians to instigate more effective management for colonic dysmotility or PFD.

Psychophysiological profile in dyssynergic defecation patients: an individual and situational response specificity analysis

The aim of this study was to evaluate the temporal stability and the situational specificity of the intra-anal EMG-activity, as well as the individual specificity of this response in dyssynergic defecation patients. With this purpose, 26 individuals (13 with dyssynergic defecation and 13 without anorectal pathology) participated in two sessions of psychophysiological assessment, with an inter-session period of 1 week. At each session, the EMG-activity of external anal sphincter was recorded under four different conditions (baseline, voluntary contraction, reflex contraction and simulated defecation). The findings provide empirical evidence about temporal stability of the intra-anal EMG-activity, situational specificity of this response and the existence of a specific profile of intra-anal EMG-activity characteristic of patients with dyssynergic defecation.

Comparative study between biofeedback retraining and botulinum neurotoxin in the treatment of anismus patients

PURPOSE

Anismus is a significant cause of chronic constipation. This study came to revive the results of BFB training and BTX-A injection in the treatment of anismus patients.

MATERIALS AND METHODS

Forty-eight patients with anismus (33 women; mean age 39.6 +/- 15.9) were included in this study. All patients fulfilled Rome II criteria for functional constipation. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography (EMG) activity of the EAS. All patients had non-relaxing puborectalis muscle. The patients were randomized into two groups. Group I patients received biofeedback therapy, two times per week for about 1 month. Group II patients were injected with BTX-A. Follow-up was conducted weekly in the first month then monthly for about 1 year.

RESULTS

In the BFB training group, three patients quit before the end of sessions with no improvement; initial improvement was recorded in 12 patients (50%) while long-term success was recorded in six patients (25%). In the BTX-A group, clinical improvement was recorded in 17 patients (70.83%), but the improvement persisted only in eight patients (33.3%). There is a significant difference between BTX-A group and BFB group regarding the initial success, but this significant difference disappeared at the end of follow-up. Manometric relaxation was achieved significantly post-BFB and post-BTX-A injection with no significant difference between the two groups.

CONCLUSIONS

Biofeedback training has a limited therapeutic effect on patients suffering from anismus. BTX-A injection seems to be successful for temporary treatment of anismus.

Audit of constipation in a gastroenterology referral center

This study was designed to assess the various subtypes of functional constipation in a referral gastrointestinal center of a Latino-American country. All patients referred for evaluation of constipation during a 10-year period were audited, and those with functional constipation according to Rome I criteria classified by physiologic tests of colonic transit, as well as tests of anorectal and pelvic floor function. More than 70% of patients with functional constipation had evidence of pelvic floor dysfunction, whereas those with slow transit and constipation-predominant irritable bowel syndrome subtypes were less frequently represented. Even in a setting different from those most frequently reported in the literature, pelvic floor dysfunction represents the most common cause of functional constipation. Simple, physiologic testing is needed and useful for the diagnosis. This fact has therapeutic implications, especially because many such patients may benefit from biofeedback.

Defecación obstructiva. Métodos diagnósticos y tratamiento

Obstructive defecation is observed in approximately half of all patients with functional constipation. Functional constipation has been related to alterations in intestinal motility (slow transit constipation) and to pelvic floor disorders leading to obstructive defecation associated with anatomical alterations of the pelvic floor (rectocele, posterior perineal hernia, enterocele and sigmoidocele, internal rectal intussusception, occult mucosal prolapse, solitary rectal ulcer and descending perineum syndrome), or obstructive defecation without anatomical alterations (pelvic floor dyssynergy or anismus). The diagnostic methods used (history and physical examination, colonic transit time, balloon expulsion test, proctography, anorectal manometry and electromyography) are reviewed. Conservative medical treatment and the indications for surgical treatment and its results are also discussed.

Manometric assessment of idiopathic megarectum in constipated children

AIM: Chronic constipation is a frequent finding in children. In this age range, the concomitant occurrence of megarectum is not uncommon. However, the definition of megarectum is variable, and a few data exist for Italy. We studied anorectal manometric variables and sensation in a group of constipated children with megarectum defined by radiologic criteria. Data from this group were compared with those obtained in a similar group of children with recurrent abdominal pain.

METHODS: Anorectal testing was carried out in both groups by standard manometric technique and rectal balloon expulsion test.

RESULTS: Megarectum patients displayed discrete abnormalities of anorectal variables and sensation with respect to controls. In particular, the pelvic floor function appeared to be impaired in most patients.

CONCLUSION: Constipated children with megarectum have abnormal anorectal function and sensation. These findings may be helpful for a better understanding of the pathophysiological basis of this condition.

Posterior pelvic floor compartment disorders

Posterior pelvic floor compartment disorders generally refer to functional anorectal disturbances that by definition are symptom-based rather than anatomical defect-based and have a significant impact on quality of life. Symptoms attributed to the posterior compartment are often non-specific and associated with structural, neuromuscular and functional defects giving rise to symptoms of prolapse, pelvic pressure, faecal incontinence, stool trapping and constipation. They may range from mild to incapacitating and occur in varying combinations. While symptoms of constipation and incontinence may conceptually represent the opposing extremes of normal anorectal function, the dynamic interrelationships between the different pathophysiological mechanisms involved in the development of these disorders suggest a more complex explanation. Faecal continence and defecation are dependent on several neurological and anatomical factors that involve coordinated physiological processes, including intestinal transit and absorption, colonic transit, rectal compliance, anorectal sensation and continence mechanism. However, it is well recognized that pelvic floor symptoms originating from one compartment do not imply absent pathology in another compartment. Furthermore, symptoms associated with one disorder (such as constipation related to functional obstructed defecation) can be causative in the sequential development of other pelvic floor disorders, such as a urogenital prolapse syndrome, that may further exacerbate symptoms. In addition, it has been found that treatment that corrects one problem may improve, worsen or even predispose to other symptoms from another compartment. Consequently, while the concept of global pelvic floor dysfunction has emerged, the traditional single speciality referral and evaluation of pelvic floor problems continues to foster potentially segregated management strategies that can overlook the relevance of concomitant symptomatology. The evaluation and treatment of posterior pelvic compartment disorders needs to assume an individualized but multidisciplinary therapeutic approach. Given the variation in surgical approaches described to correct anatomical integrity of posterior pelvic compartment deficits, the consensus on optimal management has yet to be achieved. Therefore, it is critical that outcome measures following surgery are clearly defined. Treatment is to a great extent dictated to by functional severity and the impact that symptoms have on quality of life. Long-term follow-up should ensure that the potential for complications is minimized and satisfactory bowel, bladder and sexual function is maintained.

Predictive value of the balloon expulsion test for excluding the diagnosis of pelvic floor dyssynergia in constipation

BACKGROUND AND AIMS

The aim of this study was to establish a simple method to exclude the possibility of pelvic floor dyssynergia (PFD) in constipated patients and thus avoid unnecessary expensive physiologic studies.

METHODS

Patients with suspicion of functional constipation (FC) were studied prospectively between 1994 and 2002, excluding those with severe systemic, psychological, or symptomatic anorectal/colonic disorders or taking medications that might modify symptoms or results of studies. Diagnosis of PFD was established retrospectively by manometric plus defecographic findings according to Rome II criteria. Two groups of patients were identified: FC without PFD (FC group) and PFD group. A 30-day symptom diary and balloon expulsion test results were evaluated in all patients. Clinical differences and results of the expulsion test were statistically compared between groups.

RESULTS

Of 359 patients evaluated, 130 were included (FC group, 106; PFD group, 24). According to data from the diary, only anal pain was more frequent in the PFD group compared with the FC group (anal pain in >25% of defecations, 70.8% vs. 40.6%; P < 0.05, chi(2) test). The expulsion test was pathologic in 21 of 24 patients with PFD and 12 of 106 without PFD. The specificity and negative predictive value of the test for excluding PFD were 89% and 97%, respectively.

CONCLUSIONS

The balloon expulsion test is a simple and useful screening procedure to identify constipated patients who do not have PFD. Symptoms are not enough to differentiate between subtypes of constipation.

On the pathogenesis of rectocele: the concept of the rectovaginal pressure gradient

Coughing or straining evokes reflex bulbocavernosus (BCM) and puborectalis (PRM) muscle contraction, which apparently transforms the vagina into a closed high-pressure cavity. This elevated vaginal pressure counteracts the increased intra-abdominal pressure and the tendency of the uterus to prolapse, and also supports the rectovaginal septum against the high straining-induced intrarectal pressure and possible consequent rectocele (posterior vaginal prolapse) formation. We investigated the hypothesis that a weak BCM and PRM share in the genesis of rectocele by changing the rectovaginal pressure gradient. Twenty-three women with rectocele (mean age 43.2+/-6.6 years) and 12 healthy women volunteers (mean age 41.6+/-6.2 years) were studied. The response of the intrarectal (intra-abdominal) and intravaginal pressure, as well as the EMG activity of the BCM and PRM to straining or coughing, was recorded. In the healthy volunteers the rectal and vaginal pressures showed a significant increase on coughing or straining, with no significant difference between the rectal or vaginal pressures. Also, the BCM and PRM EMG activity exhibited a significant increase. Rectocele patients showed a significantly low resting vaginal pressure. The increase in rectal and vaginal pressure, as well as of the EMG activity of the BCM and PRM on straining or coughing, was significantly lower and the latency of the EMG response was significantly longer than those of the healthy volunteers. A difference in the rectovaginal pressure gradient showing a significant increase in the rectal against the vaginal pressure, particularly on coughing or straining, is suggested to be the basic factor in the genesis of rectocele. This pressure difference appears to be caused by diminished BCM and PRM contractile activity. A disrupted rectovaginal septum is not a prerequisite for rectocele formation, as the septum appears normal in obstructed defecation despite the common occurrence of rectocele. A histopathologic study of the septum in rectocele seems necessary.

Obstructed defecation

BACKGROUND

In the last decade our understanding of pelvic floor function and dysfunction has improved significantly. A more rational diagnostic and therapeutic approach is now possible for the group of patients with constipation due to obstructed defecation (OD).

METHODS

The review is based on a literature search using the PubMed database focusing mainly on recent literature addressing the subject.

RESULTS

Obstructed defecation occurs in about 7% of the adult population. Different pathophysiological mechanisms, either functional or anatomical, eventually lead to OD. Different tests (defecography, balloon evacuation test, manometry, electromyography, colonic transit time measurementmanometry) play an important role to quantify the problem. These tests are not without problems as abnormal results are also found in asymptomatic controls. Also, there is poor agreement between different tests and a poor correlation with symptomatology. Thus, for most syndromes conservative treatment including biofeedback is appropriate. Surgery can yield excellent results in selected cases.

CONCLUSION

Validation of scoring systems and quantitative tests is still needed. More uniform and strict criteria for anismus should be applied to make therapeutic approaches comparable. Appropriate selection of patients for surgery is the key to success.

Study of the role of the second defecation reflex: anorectal excitatory reflex in the pathogenesis of constipation

BACKGROUND

Previous studies have shown that anal distension caused rectal contraction, an action mediated through the anorectal excitatory reflex. Anal anesthetization aborted rectal contraction and rectal evacuation was induced by excessive straining. We investigated the hypothesis that inhibition or absence of the anorectal excitatory reflex could lead to constipation.

METHODS

We studied 18 patients (mean age +/- SD: 40.6 +/- 5.8 years, 14 women) with rectal inertia, 14 (41.7 +/- 6.6 years, 12 women) with puborectalis paradoxical syndrome, and 10 healthy volunteers (37.9 +/- 4.8 years, 8 women). The rectum was filled with normal saline until urge and then evacuated; residual fluid was calculated. The anal and rectal pressure response to anal balloon distension in increments of 2 mL of saline was recorded by a two-channel microtip catheter.

RESULTS

In the healthy volunteers, saline was evacuated as a continuous stream without straining except occasionally at the start of evacuation; no residual fluid was encountered. Anal balloon distension effected notable rectal pressure increase. In rectal inertia patients, evacuation occurred in small fluid gushes produced with excessive straining; residual fluid of large volume was collected. Anal balloon distension up to 10 mL produced no notable rectal pressure changes. The patients with PPS failed to evacuate more than a few mL of fluid despite excessive straining; the volume of residual fluid was considerable. Anal balloon distension caused a notable rectal pressure rise. The results were reproducible.

CONCLUSIONS

These results suggest that the defecation reflexes (rectoanal and anorectal) are absent in rectal inertia patients and this presumably denotes a neurogenic disorder. The anorectal reflex is active in puborectalis paradoxical syndrome, but the rectoanal reflex is not, indicating a possible myogenic defect in the puborectalis muscle.

Dynamic evaluation of the anorectum

The evaluation of EP is complicated by the lack of any gold standard and a shifting clinical emphasis as management regimens go in and out of favor. As with all functional bowel disease, there is a residue of patients who are difficult to manage, and in whom a clinician will want maximum information before deciding on treatment. The examination has been criticized as lacking clinical relevance, and of having poor interobserver reliability except for rectal emptying and rectocele formation. Others have found a higher (83.3%) observer accuracy and a high yield of positive diagnoses. A questionnaire showed that clinicians found EP of major benefit in 40%, altering management from surgical to medical in 14% and vice versa in 4%. Radiographic examinations only impact on clinical management when findings alter management. Management protocols are evolving in functional disorders, but important features that EP reveals are anismus, trapping in rectoceles, IAI, and rectal prolapse. EP is the only method to diagnose some of these conditions and within defined parameters is extremely valuable in clinical management.

Study of the motile activity of the colon in rectal inertia constipation

BACKGROUND

We have recently demonstrated that rectal distension effected left colonic contraction, which probably acts to feed the rectum with fecal matter each time the rectum distends and evacuates its contents. This effect was postulated to occur through the recto-colic reflex. As the colonic status in rectal inertia constipation was scarcely addressed in the literature, we investigated this point.

METHODS

The response of the colonic pressure to rectal balloon distension in increments of 10 mL of water was studied in 38 patients with rectal inertia constipation (IC) (age 42.6 +/- 14.3 years, 29 women) and 12 healthy volunteers (40.9 +/- 12.2 years, nine women). The rectal and colonic pressures were measured by saline-perfused tubes connected to a pneumohydraulic infusion system. The rectum was distended by a condom applied to the end of a 10-F catheter.

RESULTS

The rectal and left colonic resting pressures were significantly lower in the patients than in the controls (P < 0.5, P < 0.05, respectively). In the healthy volunteers, rectal distension up to first rectal sensation produced no significant rectal or colonic pressure changes (P > 0.05, P > 0.05). At urge, rectal and left colonic pressures increased significantly (P < 0.001, P < 0.001, respectively), but there were no changes in the right colonic pressure (P > 0.05). The colonic response lasted as long as the rectum was distended. In IC, patients did not perceive the first rectal or urge sensation up to a rectal balloon filling of 300 mL; there was no rectal or colonic pressure response (P > 0.05, P > 0.05).

CONCLUSION

In normal subjects, left colonic contraction on rectal distension probably acts to feed the rectum with fecal material. In IC, the low left colonic resting pressure assumedly points to left colonic hypotonia which appears to aggravate the constipation produced by the inertic rectum. Furthermore, non-response of the left colon to rectal distension probably impedes rectal feeding with fecal matter and enhances constipation.

Slow transit constipation in children

Patients with chronic constipation that fails to respond to treatment remain a challenge for paediatricians and surgeons. Ongoing work in our institution suggests that a number of children with intractable symptoms have slow transit constipation, which has only been described recently in paediatrics. Common features of slow transit are: delayed passage of the first meconium stool beyond 24 h of age, symptoms of severe constipation within a year, or treatment-resistant 'encopresis' at 2-3 years, soft stools despite infrequent bowel actions, and delay in colonic transit on a transit study. A proportion of children with slow transit constipation have an abnormality of intestinal innervation associated with the dysfunctional colonic motility, recognized as intestinal neuronal dysplasia (IND). Intestinal neuronal dysplasia type B, the most common variant of IND, is defined on rectal biopsy by hyperplasia of the submucosal plexus. On laparoscopic colon muscle biopsy, many specimens show reduced numbers of excitatory substance P-immunoreactive nerve fibres in the circular muscle. Functional markers of the nerves allow new diagnostic criteria to be developed which may also allow a more rational approach to treatment. The aetiology remains obscure and the optimal management poorly defined, although subtotal colectomy, proximal colostomy or appendicostomy (for antegrade enemas) have been tried. Once the anatomy and physiology of the colon in children with slow colonic transit is better understood, we will have defined not only a new form of constipation, but also will be able to consider new therapies.

Electromyography of the pelvic floor musculature in the assessment of obstructed defecation symptoms

PURPOSE

The purpose of this study was to use electromyography to examine the behavior of the external sphincter, puborectalis muscle, and pubococcygeus muscle during attempted defecation in patients with symptoms of obstructed defecation and in normal subjects to highlight differences of clinical significance.

METHODS

A total of 35 patients (31 females) aged 20 to 80 (mean, 53.7 +/- 13.3) years with unprepared bowel who had normal colon transit time and obstructed defecation symptoms and 12 voluntary control subjects (7 females) aged 23 to 68 (mean, 48 +/- 11.5) years underwent an electromyography evaluation of the activity of the external sphincter, puborectalis muscle, and pubococcygeus muscle during attempted defecation. The patients were also examined in separate sessions with defecography and anal manometry.

RESULTS

During attempted defecation, puborectalis muscle and external sphincter always reacted in the same manner. When evaluated with pubococcygeus muscle, three main patterns of activity were observed either in patients or in controls: 1) coordinated activation pattern; 2) coordinated inhibition pattern; and 3) uncoordinated or equivocal pattern: activation of pubococcygeus muscle with inhibition of puborectalis muscle/external sphincter, activation followed by inhibition of the three muscles, and activation followed by inhibition of pubococcygeus muscle and no change in the others. We never observed activation of puborectalis muscle/external sphincter concomitant with inhibition of pubococcygeus muscle. The inhibitory coordinated pattern occurred significantly (P = 0.01) more frequently in controls than in patients. These subjects also presented a significantly (P = 0.01) lower frequency of pubococcygeus muscle inhibition.

CONCLUSIONS

Either activation or inhibition appears as a physiological behavior, possibly adopted in different circumstances, of the pelvic floor muscles during attempted defecation. The higher prevalence of coordinated inhibitory patterns in normal subjects and the lower frequency of pubococcygeus muscle inhibition in patients with symptoms of obstructed defecation, however, suggests that a loss of inhibition capacity progressing from pubococcygeus muscle to puborectalis muscle/external sphincter muscles could determine the insurgence of obstructed defecation symptoms in some subjects, who should therefore benefit from biofeedback retraining aimed at reacquisition of the inhibition capacity of all muscles of the pelvic floor during defecation.

An increased rectal maximum tolerable volume and long anal canal are associated with poor short-term response to biofeedback therapy for patients with anismus with decreased bowel frequency and normal colonic transit time

PURPOSE

Biofeedback is an effective therapy for a majority of patients with anismus. However, a significant proportion of patients still failed to respond to biofeedback, and little has been known about the factors that predict response to biofeedback. We evaluated the factors associated with poor response to biofeedback.

METHODS

Biofeedback therapy was offered to 45 patients with anismus with decreased bowel frequency (less than three times per week) and normal colonic transit time. Any differences in demographics, symptoms, and parameters of anorectal physiologic tests were sought between responders (in whom bowel frequency increased up to three times or more per week after biofeedback) and nonresponders (in whom bowel frequency remained less than three times per week).

RESULTS

Thirty-one patients (68.9 percent) responded to biofeedback and 14 patients (31.1 percent) did not. Anal canal length was longer in nonresponders than in responders (4.53 +/- 0.5 vs. 4.08 +/- 0.56 cm; P = 0.02), and rectal maximum tolerable volume was larger in nonresponders than in responders. (361 +/- 87 vs. 302 +/- 69 ml; P = 0.02). Anal canal length and rectal maximum tolerable volume showed significant differences between responders and nonresponders on multivariate analysis (P = 0.027 and P = 0.034, respectively).

CONCLUSIONS

This study showed that a long anal canal and increased rectal maximum tolerable volume are associated with poor short-term response to biofeedback for patients with anismus with decreased bowel frequency and normal colonic transit time.

Prognostic significance of rectocele, intussusception, and abnormal perineal descent in biofeedback treatment for constipated patients with paradoxical puborectalis contraction

PURPOSE

The findings of paradoxical puborectalis contraction, rectocele, sigmoidocele, intussusception, and abnormal perineal descent often coexist in constipated patients, as noted by defecographic study. Moreover, some of these conditions are often found in asymptomatic patients. Biofeedback is the treatment of choice for constipated patients with paradoxical puborectalis contraction; the main determinant of successful biofeedback is patient compliance. The significance of coexistent and highly prevalent variants, such as rectocele, intussusception, sigmoidocele, or abnormal perineal descent, on the success of biofeedback is unknown. This review was designed to assess whether these coexisting defecographic findings have any prognostic significance for the outcome of biofeedback.

METHODS

From July 1988 to December 1996, 209 constipated patients with paradoxical puborectalis contraction underwent biofeedback treatment after defecography. A total of 173 patients (120 females) who had more than one biofeedback session after defecography formed the study group. Defecographic findings included concomitant rectoceles, 40 (23 percent); evidence of circumferential intussusception, 17 (10 percent); sigmoidocele, 13 (8 percent); and abnormal perineal descent, 109 (63 percent).

RESULTS

Whereas 65 patients failed to complete the course of biofeedback therapy, 108 (62.4 percent) patients completed the course of biofeedback and were discharged by the therapist. Within the completed group 59 (55 percent) improved, and 49 (45 percent) patients failed biofeedback therapy. In the improved group 14 (23.7 percent) had a rectocele, 5 (8.5 percent) had intussusception, 5 (8.5 percent) had a sigmoidocele, and 37 (62.7 percent) had abnormal perineal descent. In the failure group 9 (18.4 percent) had a rectocele, 5 (10.2 percent) had an intussusception, 2 (4.1 percent) had a sigmoidocele, and 31 (63.3 percent) had abnormal perineal descent (P = not significant). The success of biofeedback was then analyzed relative to the number of coexisting conditions. Specifically, the outcome in patients with paradoxical puborectalis contraction alone and with one, two, and three other defecographic findings were compared. No statistically significant difference was found among these four groups.

CONCLUSION

Although other defecographic findings frequently coexist with paradoxical puborectalis contraction, none of the concomitant findings adversely affected the outcome of biofeedback treatment. Therefore, biofeedback can be recommended to patients with coexistent defecographic findings, with expectation of success in over 50 percent of individuals who complete the course of therapy.

Slow transit constipation: a model of human gut dysmotility. Review of possible aetiologies

Slow transit constipation is a severe condition of gut dysmotility that predominantly affects young women and may result in surgical intervention. Current medical treatments for STC are often ineffective, and the outcome of surgery is unpredictable. STC was first described almost a century ago. Since this time, progress in improving therapy for this condition has been complicated by a lack of understanding of the aetiology, and great variation in the methods and criteria used for the study of patients with this debilitating disorder. It is difficult to find unequivocal data, and harder still to give a definitive picture of the cause or causes of STC. Here we consider the evidence for various aetiologies of STC, in the light of the physiological and pathological findings.

Pelvic floor study in patients with obstructive defecation: influence of biofeedback

The aim of this study was to evaluate the pathophysiologic abnormalities in patients with obstructive defecation or dyssynergia and to assess the role of biofeedback treatment. Three groups were studied. Group A had 24 patients with obstructive defecation; B, 25 patients with constipation; and C, 22 healthy volunteers. Rectosigmoid segmental transit time of group A was 28.5 hours (SD +/- 13.4); B, 17.2 hours (SD +/- 11.5); and C, 8.5 hours (SD +/- 6.3) (p < 0.05). There was no statistical difference in resting and squeezing anal pressure among the three groups. Anorectal angle at rest revealed no difference among the three groups. At strain, a statistically significant difference between groups A and C (p < 0.05) and a marginal difference between groups A and B was noted. Rectocele of the anterior rectal wall was present at strain in 17/24 patients of group A and 7/22 patients of group C (p < 0.05). Electromyography during strain revealed abnormal contractions of puborectalis muscle and external anal sphincter, in 13 and 14 patients of group A, respectively, which differed from that observed in groups B and C (p < 0.001). Biofeedback treatment was applied with good results in 7 of 11 patients of group A. At six months, constipation relapsed in only one of treated patients. Patients suffering from obstructive defecation seem to have slower rectosigmoid transit time than the others. Defecography shows smaller anorectal angle at strain and rectocele of the anterior rectal wall more often. Abnormal pelvic floor contraction at strain is often noted in anal electromyography. Some of these patients seem to respond favorably to biofeedback treatment.

Transanal repair of rectocele corrects obstructed defecation if it is not associated with anismus

PURPOSE

Rectocele is often associated with anorectal symptoms. Various surgical techniques have been described to repair the rectocele. The surgical results are variable. This study evaluated the results of transanal repair of rectocele, with particular emphasis on the impact of concomitant anismus on postoperative functional outcome.

METHODS

Fifty-nine consecutive females who underwent transanal repair of rectocele for obstructed defecation were prospectively reviewed. All 59 patients were parous with a median parity of 2 (range, 1-6) and a median age of 58 (range, 46-68) years. The median length of follow-up was 19 (range, 6-40) months. Anismus was detected by anorectal physiology and defecography. The functional outcome was assessed by a standard questionnaire, physical examination, anorectal manometry, neurophysiology, and defecography. The quality-of-life index was obtained using a visual analog scale (from 1-10, with 10 being the best).

RESULTS

The functional outcome of transanal repair of rectocele was superior in patients without anismus. Forty (93 percent) of the 43 patients without anismus showed improved evacuation after repair compared with 6 (38 percent) of the 16 patients with anismus (P<0.05). The quality-of-life index improved (9 vs. 4) if anismus was not present (P<0.05). There were minimal complications. Hemorrhage requiring blood transfusion (2 units) occurred in one patient and urinary retention in another.

CONCLUSION

Transanal repair of rectocele is safe and, in the absence of anismus, effectively corrects obstructed defecation.

Clinical value of symptom assessment in patients with constipation

PURPOSE

This study was designed to evaluate symptoms and clinical findings in a prospective series of patients with chronic constipation.

METHODS

A total of 155 consecutive patients with intractable constipation underwent detailed symptom registration, anorectal manometry, electromyography, colonic transit time measurement, and defecography.

RESULTS

All investigations were completed by 134 patients (112 females) with a median age of 52 (range, 17-79) years. Whole-gut transit time was delayed in 55 patients (41 percent), pelvic floor dysfunction was diagnosed in 59 patients (44 percent), but in 35 percent of patients both transit time and pelvic floor function were found to be normal. Three symptoms were shown to have an independent value for the diagnosis of slow-transit constipation. Patients with slow transit more often reported two or fewer stools per week (84 vs. 46 percent), laxative dependence (87 vs. 44 percent), and a history of constipation since childhood (58 vs. 22 percent) than did those with normal transit. Pelvic floor dysfunction was associated with a higher prevalence of backache (53 vs. 33 percent) and a lower prevalence of normal stool frequency (19 vs. 36 percent), heartburn (12 vs. 27 percent), and a history of anorectal surgery (7 vs. 21 percent) compared with those with normal pelvic floor function. All four symptoms retained an independent value in the logistic regression analysis for pelvic floor dysfunction. Two symptoms characterized the group with normal transit and normal pelvic floor function: normal stool frequency and alternating diarrhea and constipation.

CONCLUSIONS

Symptoms are good predictors of transit time but poorer predictors of pelvic floor function in patients with constipation.

Electromyography of the external anal sphincter: comparison between needle and surface electrodes

PURPOSE

Electromyography of the external anal sphincter is frequently used when investigating patients with defecation disorders. Investigations are often performed using an invasive technique by perineal insertion of a needle or wire electrode. The aim of the present study was to investigate whether surface electromyography, with electrodes applied to the perineal skin, is a reliable method in the diagnosis of paradoxical anal sphincter reaction.

METHODS

Seventy-one patients with defecation disorders participated in the present study. They were investigated with electromyography of the external anal sphincter using surface and needle electrodes.

RESULTS

In 65 of 71 (92 percent) patients the electromyography recording showed the same result during straining using surface electrodes when compared with needle electrodes. Twenty-two of these 65 patients had paradoxical anal sphincter reaction, and 43 patients had decreased electromyography activity. In 6 of 71 (8 percent) patients the electromyography recording showed a different pattern during straining using surface electrodes when compared with needle electrodes.

CONCLUSION

The present study demonstrates a good correlation between surface electrodes applied to the perineal skin and concentric needle electrodes in the diagnosis of paradoxical anal sphincter reaction. Noninvasive electromyography recordings of the external anal sphincter are often preferred in the diagnosis of paradoxical anal sphincter reaction.

Biofeedback for anismus: has placebo effect been overlooked?

OBJECTIVE

Multiple uncontrolled studies have concluded that biofeedback is successful in treating anismus. This study's objective was to assess the physiological effects of placebo and biofeedback treatment on patients with anismus and to correlate changes with clinical improvement.

PATIENTS AND METHODS

Twelve patients with symptoms and electrophysiological findings of anismus were studied. Initial assessment included a detailed history, symptom assessment by linear analogue scales, anorectal manometric and electrophysiological studies, colon transit scintigraphy, and scintigraphic proctography. Patients underwent 5 days of placebo treatment, followed 1 week later by re-assessment of symptoms and physiological studies. Five days of biofeedback was then given followed by another complete re-assessment 1 week later. A final interview was performed 2 months later. All assessments were by an independent observer who was not responsible for the treatments.

RESULTS

Seven patients reported an overall improvement in symptoms following placebo treatment. A total of seven patients reported improvement following biofeedback, three of whom had already reported an improvement with placebo. One patient who reported improvement following placebo had worsening of symptoms following biofeedback. The only symptoms or tests which changed more with biofeedback than placebo were anal pressure and electromyographic activity on attempted defaecation in the left lateral position. There was no demonstrable correlation between change in symptoms and change in physiological tests. The scintigraphic 'ejection fraction' of the rectum was unchanged by treatment.

CONCLUSION

Clinical improvement in previous studies may in part be due to placebo effect and observer bias. Improvement with biofeedback may be due to physiological changes which are not detected with conventional anorectal physiological tests.

Clinical significance of anismus in encopresis

Treatments designed to relieve paradoxical contraction of the anal sphincters during defecation (anismus) have had limited success in children with encopresis. This has raised doubts as to the clinical relevance of this diagnosis in childhood as anorectal dysfunction. Our aim was to determine whether, in patients who had treatment-resistant encopresis, the presence of electromyographic anismus was associated with increased faecal retention. Sixty-eight children with soiling (mean age 8.7+/-2.06 years) were assessed by clinical examination, abdominal radiography and then with anorectal manometry. Patients with electromyographic anismus (n=32; 47%) had significantly increased radiographic rectal faecal retention and were significantly less likely to be able to defecate water-filled balloons. There were no significant differences in response to prior therapy, history of primary encopresis, behavioural adjustment or in sociodemographic data. Our results suggest that electromyographic anismus is associated with obstructed defecation and faecal retention.

Paradoxical sphincter reaction is influenced by rectal filling volume

PURPOSE

Paradoxical sphincter reaction is frequently found in constipated patients but sometimes also in incontinent patients and in asymptomatic subjects. Its significance in defecation disorders has, therefore, been debated. The aim of the present study was to investigate whether paradoxical sphincter reaction is influenced by rectal filling volume.

PATIENTS AND METHODS

Eighteen patients with defecation disorders and paradoxical sphincter reaction shown by electromyography were reinvestigated with an extended electromyographic investigation while in the lying position and while in the sitting position, with 50-ml, 100-ml, and 150-ml water-filled rectal balloons.

RESULTS

All 18 patients showing paradoxical sphincter reaction in the first investigation also showed the reaction at the second investigation in the lying position with a 0-ml volume of rectal contents. In the sitting position, with a volume of 150 ml of rectal contents, the increase in electromyographic activity disappeared in seven patients (39 percent) and no longer showed paradoxical sphincter reaction. Electromyography showed decreased activity in one patient and unchanged activity in six patients during straining. A closing reflex was seen after completed straining in all of these seven patients.

CONCLUSIONS

The present study demonstrates that paradoxical sphincter reaction diagnosed by electromyography is influenced by the rectal filling volume and might diminish when the rectum is filled with contents. The conventional electrophysiologic technique in the diagnosis of paradoxical sphincter reaction might, therefore, overdiagnose this condition.

Rectal wall contractility in response to an evoked urge to defecate in patients with obstructed defecation

PURPOSE

The aim of this study was to examine rectal sensory perception and rectal wall contractility in response to an evoked urge to defecate and to identify differences between control subjects and patients with obstructed defecation.

METHODS

Twenty control patients (10 men; median age, 47 (range, 17-78) years) and 29 female patients with disabling obstructed defecation (median age, 48 (range, 18-70) years) entered the study. Under radiologic control, an infinitely compliant barostat balloon was inserted over a guide wire into the proximal part of the rectum. Additionally, a latex balloon was introduced into the distal part of the rectum. This latex balloon was inflated until an urge to defecate was experienced. Simultaneously, rectal wall contractility was assessed by measuring the variations in barostat balloon volume. These variations were expressed as percentage changes from baseline volume.

RESULTS

By comparing controls and patients with obstructed defecation, a significant difference was found regarding mean distending volume required to elicit an urge to defecate (135 +/- 38 vs. 214 +/- 87 ml of air; P < 0.001, Mann-Whitney U-test). In all controls, the evocation of an urge to defecate induced a pronounced increase in rectal tone, proximal to the distal stimulating balloon. By comparing controls and patients, the increase in rectal tone was found to be significantly higher in control subjects (35 +/- 10 vs. 9 +/- 10 percent; P < 0.001). Twenty-five patients (86 percent) showed no or only minimum (<20 percent) increase in rectal tone during the perception of an urge to defecate. In 14 of these patients, the threshold for this perception was increased. Only four patients (14 percent) showed a relatively normal increase (>20 percent) in rectal tone. However, their threshold for perception was greatly increased.

CONCLUSION

The assembly used in this study provides a useful tool for investigation of rectal evacuation. In all of our patients, obstructed defecation was associated with abnormal rectal sensory perception and/or altered rectal wall contractility.

Quality of life in patients with different types of functional constipation

BACKGROUND

Little information is available about the health-related quality of life (QoL) in patients with different types of chronic constipation.

METHODS

We used two self-administered questionnaires, the Psychological General Well-Being (PGWB) index and the Gastrointestinal Symptom Rating Scale (GSRS) to assess QoL and gastrointestinal symptoms in 102 consecutive patients with chronic constipation. The type of constipation was determined from transit time, electrophysiologic investigation of sphincter function, anorectal manometry, and defecography.

RESULTS

Overall, our patients with constipation reported low scores for general well-being (mean score, 85.5, compared with 102.9 in a healthy population). Patients with normal-transit constipation (n = 49) reported considerably lower scores in the PGWB than those with slow-transit constipation (n = 35). The symptoms increased frequency of defecation, loose stools, and urgent need for defecation were commoner in normal-transit constipation, which indicates that this group may have a relation to the irritable bowel syndrome. The overall PGWB index was strongly correlated with the total GSRS (P < 0.001).

CONCLUSIONS

The general well-being of patients with chronic constipation is lower than that of a comparable normal population. Symptom severity correlates negatively with perceived quality of life.

Prospective study of biofeedback for treatment of constipation

PURPOSE

This study was designed to evaluate prospectively the results of pelvic floor physiotherapy with the aid of biofeedback in a heterogeneous group of patients with intractable constipation.

METHODS

Biofeedback was used to treat 19 patients (age range, 16-78 (median, 63) years) with intractable constipation. Assessment, using visual linear analog scales of symptoms, was performed prospectively by an independent researcher. Biofeedback was performed by a physiotherapist, and patients were required to attend six sessions on an outpatient basis. The cause of constipation was heterogeneous, with no specific disorder being implicated on testing with anal manometry, defecating proctography, and colonic transit time.

RESULTS

At six weeks, there was a median 27 percent (range, -8-93 percent) improvement in symptom scores. At six months, there was a median 23 percent (range, -54-64 percent) improvement in symptom scores. These were statistically significant compared with the scores at outset, six weeks (P = 0.0006), and six months (P = 0.012). However, only two (12.5 percent) patients at the six-month follow-up had an improvement of greater than 50 percent in their symptoms.

CONCLUSION

Biofeedback is not recommended in the management of constipation.

Anismus: fact or fiction?

PURPOSE

Although anismus has been considered to be the principal cause of anorectal outlet obstruction, it is doubtful whether contraction of the puborectalis muscle during straining is paradoxical. The present study was conducted to answer this question.

METHODS

During the first part of the study, we retrospectively reviewed 121 patients with constipation and/or obstructed defecation (male:female, 10/111; median age, 51 years). All of these patients underwent electromyography (EMG) of the pelvic floor and the balloon expulsion test (BET) in the left lateral position. Evacuation proctography was performed in all of these patients in the sitting position. Both the posterior anorectal angle and the central anorectal angle were measured. EMG and BET were also performed in ten controls (male:female, 4/6; median age, 47). In 147 patients with fecal incontinence (male:female, 24/123; median age, 58) only EMG activity was recorded. Criteria for anismus during straining were increase or insufficient (<20 percent) decrease of EMG activity, failure to expel an air-filled balloon on BET, and decrease or insufficient (<5 percent) increase of anorectal angle on evacuation proctography. Between June 1994 and March 1995, we conducted a second prospective study in a consecutive series of 49 patients with constipation and/or obstructed defecation and 28 patients with fecal incontinence. Both groups were compared with 19 control subjects. In this study, all three tests were performed. EMG and BET were performed both in the left lateral position and in the sitting position.

RESULTS

The retrospective study was undertaken by comparing the constipated patients with the incontinent patients and the controls, and the anismus detected by EMG was found in, respectively, 60, 46, and 60 percent. Failure to expel the air-filled balloon was observed in 80 constipated patients (66 percent) and in 9 control subjects (90 percent). Based on posterior anorectal angle and central anorectal angle measurements, anismus was diagnosed in, respectively, 21 and 35 percent of constipated patients. In the prospective study, none of the tests showed significant differences regarding the prevalence of anismus between the two subgroups of patients and the control subjects. The prevalence of anismus only differed between constipated and incontinent patients when the diagnosis was based on BET in the sitting position (67 vs. 32 percent; P < 0.005). Our study shows that contraction of the puborectalis muscle during straining is not exclusively found in patients with constipation and/or obstructed defecation. The three tests most commonly used for the diagnosis of anismus showed an extremely poor agreement.

CONCLUSION

Based on these findings, we doubt the clinical significance of anismus.

Laparoscopic-assisted compared with open total colectomy in treating slow transit constipation

BACKGROUND

Total colectomy is the procedure of choice when slow transit constipation (STC) can be confidently diagnosed. A laparoscopic-assisted technique (LTC) may be potentially advantageous over traditional open technique (OTC) in the treatment of this benign condition.

METHODS

A historical control (non-randomized) study was performed on patients diagnosed to have STC after clinical, anorectal physiologic and transit marker studies. All earlier consecutive patients underwent OTC and the latter consecutive patients underwent LTC. The intra-operative time, blood loss, postoperative ileus recovery, duration of hospitalization and complications were recorded. A bowel function and patient satisfaction questionnaire was administered on follow-up.

RESULTS

Twenty-four of 411 patients were found to have STC; 17 (2 men, 15 women; mean age, 40 (standard error of mean [SEM] 5) years) underwent OTC and 7 (2 men, 5 women; mean age, 39.5 (SEM 6) years) underwent LTC. There were significant improvements in the stool frequency, need for assisted evacuation and abdominal distension (P < 0.05) after both procedures; 96% were fully satisfied with the resulting bowel function. However, OTC patients were less satisfied with the cosmetic outcome (P < 0.05). Intra-operative time for LTC was longer by a mean 74 min (P < 0.05). Postoperative blood loss, recovery of ileus and hospitalization time were the same in both groups. There were no deaths. The complication rates were 43% for LTC and 24% for OTC. The predominant complication was bowel obstruction for which two patients (both OTC) required adhesiolysis.

CONCLUSIONS

Both OTC and LTC improve bowel function for STC;LTC gives a better cosmetic result, but takes longer to perform.

Role of defecography in predicting clinical outcome of rectocele repair

PURPOSE

The aim of this study was to evaluate the role of defecography in predicting clinical outcome of rectocele repair.

METHODS

Between January 1988 and July 1994, 74 consecutive patients (median age, 54 (range, 35-81) years) with a rectocele and symptoms of obstructed defecation were studied prospectively. After preoperative evaluation by a standardized questionnaire, physical examination, and defecography, a combined transvaginal/transanal rectocele repair was performed. At follow-up, all patients had defecography. Long-term results were qualified by an independent observer after a median follow-up of 58 (range, 14-89) months as "excellent," "good," or "poor."

RESULTS

Rectocele repair was considered excellent in 37 patients and good in 13 patients. Defecography six months after surgery did not show persistent or recurrent rectocele in any of the patients. Size of the rectocele, barium-trapping in the rectocele, internal intussusception, rectal evacuation, and perineal descent did not appear to influence clinical outcome. Radiologic evidence of anismus did not correlate with long-term results of rectocele repair.

CONCLUSIONS

Combined transanal/transvaginal repair of rectocele is an efficient therapy in patients with obstructed defecation. Various defecographic parameters (size of rectocele, internal intussusception, rectal evacuation, perineal descent, radiologic signs of anismus) do not appear to influence clinical outcome of surgery. The main value of defecography is the objective demonstration of rectocele and any associated abnormalities such as an enterocele preoperatively and again in objective assessment of the postoperative results.

Defecography and proctography. Results of 744 patients

PURPOSE

Radiographic imaging of dynamic changes within the pelvic cavity and rectum during evacuation has been recognized as a valuable method of assessment. This study was designed to assess the incidence and clinical significance of defecographic findings in patients with possible evacuation disorders.

MATERIALS AND METHODS

All defecographic studies were reviewed by a single colorectal surgeon familiar with patients' histories and physical findings.

RESULTS

Between July 1988 and July 1995, 744 patients (566 females and 178 males) with a mean age of 63.5 (range, 12-95) years had defecographic and proctographic examination. Four hundred forty-six (60 percent) patients were diagnosed who complained of constipation, 123 (16.5 percent) of fecal incontinence, 42 (5.6 percent) of rectal prolapse, 82 (11 percent) of rectal pain, and 51 (6.9 percent) had a combination of more than one of these diagnoses. Although 93 (12.5 percent) of these evaluations were considered normal, 61 (8 percent) revealed rectal prolapse, 191 (25.7 percent) rectocele, 82 (11 percent) sigmoidocele, and 94 (12.6 percent) intussusception; in 223 (30 percent) patients, a combination of these findings was noted. Patients with paradoxical puborectalis contraction had an extremely high frequency of constipation compared with other symptoms (P < 0.0001).

CONCLUSIONS

Defecography can reveal abnormalities in the majority of patients with evacuatory disorders. There was a high incidence of rectocele, sigmoidocele, and intussusception. Care must be taken not to treat patients strictly based on radiographic findings.

[Defecation flowmetry. A new study technique for evaluating the evacuation function of the rectum]

In a prospective study carried out on 78 patients with chronic constipation (31, with slow transit, 47 with obstructive defecation disorders) the evacuation function of the rectum during defecation was assessed by defecoflowmetry. These patients were compared to a control group of normal volunteers (n = 32). The following parameters were evaluated: defecation and retention volume, defecation fraction, defecation time, maximum flow, mean flow rate and time to maximum flow. As expected, there was no difference in evacuation function between the group of patients with slow transit and the control group. Significant differences, however, existed between the two types of constipation, as well as between obstructive defecation disease and controls, regarding all parameters mentioned above. Evacuation function depends neither on rectal neck pressure nor on intrarectal pressure. In patients with obstructive defecation disorders, three subgroups were discernable: one with prolonged time of defecation and satisfactory evacuation, one with prolonged time of defecation and poor evacuation, and one small group of patients who were not able to defecate. Each group is based on a different underlying pathomechanism. We conclude that changes in evacuation function of the rectum refer either to volume or to time of defecation, or to both. Changes are found only in obstructive type constipation, not in slow transit constipation. Therefore, defeconflowmetry as a dynamic procedure can be used in screening for the classification of chronic constipation.

Clinical and physiologic effects of biofeedback in outlet obstruction constipation

PURPOSE

We report the results of biofeedback (BF) on patients with outlet obstruction defecation (OOC), including those with and without measurable paradoxical puborectalis contractions (PP). Clinical and anorectal physiologic parameters (ARP) were assessed one week before and after a standardized course of BF.

METHODS

Sixty-two consecutive patients (24 men, 38 women; mean age, 48 (standard error of the mean, 2.3) years) were recruited. All had persistent constipation despite six weeks of dietary fiber supplements. Colonic inertia was excluded by transit marker studies. Defecating proctography excluded anatomic abnormalities causing outlet obstruction. Patients underwent four outpatient sessions of biofeedback, each session lasting one hour.

RESULTS

After BF, 56 patients (90.3 percent) were subjectively improved. Frequency of spontaneous bowel movements were significantly increased (P = 0.003). Frequency of laxative-induced (P = 0.004) and enema-induced (P = 0.005) stools were reduced. Anal resting (P = 0.04) and squeeze (P = 0.002) pressures were increased. Number of patients with PP was reduced from 40 to 31 (P = 0.004). Presence of PP did not affect response to BF. There were no differences in ARP between the 56 patients who improved and the 6 who did not. There were no side effects or clinical regressions after a mean follow-up of 14.9 (standard error of the means, 0.9) months.

CONCLUSIONS

BF effectively treated OOC in 90.3 percent, regardless of PP. Anal pressures were increased, and PP was decreased.

Anorectal and pelvic floor function. Relevance of continence, incontinence, and constipation

Anorectal tests need to be tailored to the presentation of the individual patient. Clearly the tests are most useful when they identify anatomic or physiologic abnormalities for which there are successful treatments. For the incontinent patient, anal manometry is the most useful test. Sphincter injuries should be repaired, whereas neurogenic incontinence is best treated initially with biofeedback. Three tests are more useful for the constipated patient: colonic transit time, degree of pelvic floor descent on straining, and balloon expulsion. Colonic inertia responds to total colectomy and pelvic floor dysfunction to biofeedback. Meanwhile, patients with irritable bowel syndrome require rereferral back to their physicians.

Idiopathic megarectum in adults. An assessment of manometric and radiologic variables

Outlet obstruction is thought to be one of the major factors responsible for idiopathic constipation. However, outlet obstruction itself may be due to several mechanisms. Among these, the presence of a megarectum is a leading one. Pathophysiological studies in adult patients with idiopathic megarectum are scarce. We studied by manometric and defecographic means 15 adult subjects with idiopathic megarectum and severe chronic constipation. Twenty-five healthy volunteers of both sexes acted as controls. Manometric variables showed significant differences between patients and controls with respect to internal anal sphincter pressure (P = 0.02), minimum relaxation volume (P < 0.001), defecatory sensory threshold (P < 0.001), mean rectal tolerable volume (P < 0.001), and rectal compliance (P < 0.001). An altered response to straining was observed in 46.6% of patients and in 12% of controls (P < 0.04); the ability to expel a 50-ml balloon per anum was 13.3% in patients and 100% in controls (P < 0.001). Although all patients opened the anorectal angle and had descent of the pelvic floor, thereby confirming an adequate expulsion effort, evacuation of contrast material appeared extremely difficult. In fact, no subject was able to expel more than 30% of the rectal contents during fluoroscopic screening. These results confirm previous hypotheses that idiopathic megarectum displays features of a neuropathic process as an underlying mechanism. Further studies are needed that also take into consideration the muscle tone component of the rectum in these patients.

Obstructed defecation: current status of pathophysiology and management

Obstructed defecation poses a challenging clinical problem and in many patients presenting with this syndrome the underlying pathophysiology cannot be determined. Up to now, attempts to diagnose and treat obstructed defecation (anismus) have focused on the function of the somatic pelvic floor musculature surrounding the anorectum, and concepts such as 'puborectalis paradox' and 'spastic pelvic floor' have gained widespread acceptance despite there being no objective data to support such concepts. New evidence showing that defecation is an integrated process of colonic and rectal emptying suggests that anismus may be much more complex than a simple disorder of the pelvic floor muscles. In a small number of patients obstructed defecation is caused by a more simple mechanism, such as internal sphincter hypertonia or a large rectocele, which is easily corrected surgically. Careful selection of patients for treatment, based on identifying the underlying pathophysiological disorder, is emphasized.

[Electromyographic activity of the external anal sphincter muscle and the puborectal muscle in the defecation test in patients with obstructive defecation disorders]

In a prospective electromyographic and manometric study on 23 women (average age 52 years) with obstructive defecation disorder the activity of the external anal sphincter muscle and the puborectal muscle was investigated at rest and during contraction and straining. The control group consisted of 22 healthy women with an average age of 53 years. The main aim of the study was to investigate the functioning of the two muscles during simulated defecation (maximum strain) and to examine any changes in the pressure ratio in the rectum and the anal canal during this stimulation. There were no significant differences in the resting pressure, the contraction pressure and the straining pressure (in the rectum and the anal canal) between the two groups. The functioning of the puborectal muscle and the external anal sphincter muscle was largely the same in both the study group and the control group. No statistically significant differences were found between the two groups except in the amplitude of contraction. When we tried to list the change in the activity of the muscle as an index of anism, we were not able to objectify such a change for either the external anal sphincter muscle or the puborectal muscle. We therefore conclude that the increase in the activity of the voluntary muscle of the pelvic floor observed on electromyography during defecation does not indicate a pathologic condition but is a functional state.

Dynamic anal manometry in the assessment of patients with obstructed defecation

Patients with obstructed defecation show no consistent abnormalities when assessed by standard anorectal physiologic methods. With a recently developed technique for dynamic anal manometry, we studied 13 female patients with obstructed defecation and 20 healthy volunteers. Seven parameters of anal function were measured. There were no differences between the median values for the two groups. Seven patients (54 percent; 95 percent confidence limits, 25-81 percent) had anal compliance below the normal range, either during opening or closing of the sphincter at rest (five patients), during squeeze (one patient), or both (one patient). Opening and closing pressures of the sphincter at rest, maximal closing pressure during squeeze, and anal hysteresis were normal. Standard anal manometry did not show any differences between patients and controls. Rectal compliance was lower in patients with obstructed defecation, median difference 5 ml/cm H2O (95 percent confidence limits, 1-9 ml/cm H2O). In conclusion, the more detailed method of dynamic anal manometry shows that some patients with obstructed defecation have a less compliant anal sphincter and a less compliant rectum, but in many patients no abnormal findings can be made.

Anorectal manometry in the diagnosis of paradoxical puborectalis syndrome

This prospective study was undertaken to compare the utility of anorectal manometry (ARM) with that of anal electromyography (EMG) and cinedefecography (CD) in the diagnosis of paradoxical puborectalis syndrome (PPS). One hundred sixteen consecutive patients with a history of chronic constipation were prospectively assessed. These 35 males and 81 females were of a mean age of 60 years, ranging from 18 to 84 years. The incidences of PPS were 63 percent for ARM, 38 percent for EMG, and 36 percent for CD. The correlations of PPS were suboptimal: ARM and EMG, 70 percent; and ARM and CD, 61 percent. A two-tiered system for the manometric classification of PPS was developed. First, the evacuation pressure curve pattern was classified as a normal relaxed downward (Type A; n = 43), a nonrelaxed flat or equivocal (Type B; n = 36), and a paradoxical upward (Type C; n = 37). PPS was noted with increasing incidence within curve types (21 percent in Type A, 64 percent in Type B, and 95 percent in Type C). Second, an evacuation index (EI = evacuation pressure/squeeze pressure) was defined: Group I (EI < 0; n = 43), Group II (0 < or = EI < 0.25; n = 24), Group III (0.25 < or = EI < 0.5; n = 27), and Group IV (EI > or = 0.5; n = 18). The finding of PPS also correlated with the EI group: 21 percent in Group I, 67 percent in Group II, 74 percent in Group III, and 100 percent in Group IV. This subdivision of curve types and EI groups may provide a role in the diagnosis of PPS.

Idiopathic slow-transit constipation

Until recently, the surgical management of idiopathic slow-transit constipation had remained unchanged since the condition was first described by Arbuthnot Lane in 1908. Although colectomy and ileorectal anastomosis is a successful treatment for the majority of patients, symptoms persist or are worse in some cases following such surgery. The previously inaccessible colon is now an area of interest in both health and disease; recent observations on aetiology, clinical investigation, neuropathology and surgical outcome lead us to question the rationale of colectomy for all patients with severe constipation.

Obstructed defecation

Obstructed defecation is one of the causes of chronic constipation. Clinical tests suggest that patients with obstructed defecation have impaired pelvic floor function. Appropriate management relies on proper identification of the underlying pathophysiology.

Cinedefecography and electromyography in the diagnosis of nonrelaxing puborectalis syndrome

A prospective study was undertaken to assess the correlation between electromyography (EMG) and cinedefecography (CD) for the diagnosis of nonrelaxing puborectalis syndrome (NRPR). Clinical criteria for NRPR included straining, incomplete evacuation, tenesmus, and the need for enemas, suppositories, or digitation. EMG criteria included failure to achieve a significant decrease in electrical activity of the puborectalis (PR) during attempted evacuation. CD criteria included either paradoxical contraction or failure of relaxation of the PR along with incomplete evacuation. In addition, other etiologies for incomplete evacuation, such as rectoanal intussusception or nonemptying rectocele, were excluded by proctoscopy and defecography in all cases. One hundred twelve patients with constipation, 81 females and 31 males, with a mean age of 59 (range, 12-83) years were studied by routine office evaluation, CD, and EMG. Forty-two patients (37 percent) had evidence of NRPR on CD (rectal emptying: none, 24; incomplete, 18). Twenty-eight of these patients (67 percent) also had evidence of NRPR on EMG. EMG findings of NRPR were present in 12 of 70 patients (17 percent) with normal rectal emptying. Conversely, 14 of 72 patients (19 percent) with normal PR relaxation on EMG had an NRPR pattern on CD. The sensitivity and specificity for the EMG diagnosis of NRPR were 67 percent and 83 percent, and the positive and negative predictive values were 70 percent and 80 percent, respectively. Conversely, if EMG is considered as the ideal test for the diagnosis of NRPR, CD had a sensitivity of 70 percent, a specificity of 80 percent, and positive and negative predictive values of 66 percent and 82 percent, respectively. In summary, sensitivity, specificity, and predictive values of EMG and CD are suboptimal. Therefore, a combination of these two tests is suggested for the diagnosis of NRPR.

Evidence from dynamic integrated proctography to redefine anismus

The role of anismus in the aetiology of defective rectal evacuation was investigated by dynamic integrated proctography in 20 controls and 71 constipated patients. Normal parameters were defined and compared between 21 constipated patients with poor evacuation during proctography (< 40 per cent of contrast evacuated; group 1) and 50 who evacuated fully (> 90 per cent of contrast evacuated; group 2). Nine patients in group 1 failed to evacuate. Radiological abnormalities of the rectum were recorded in all groups but obstructed evacuation was not observed. Anismus (defined as a recruitment of puborectalis electromyogram (EMG) activity of > 50 per cent) was significantly more common in group 1 than group 2 patients (14 of 21 versus 12 of 50, P < 0.01) and present in seven of those unable to evacuate. Eight patients in group 1 failed to raise intrarectal pressure > 50 cmH2O compared with two in group 2 (P < 0.001). Six patients in group 1 demonstrated both anismus and inability to raise intrarectal pressure, which may combine to cause defective evacuation. EMG recruitment alone is insufficient to diagnose anismus. Definition should be based on three criteria: demonstration of puborectalis EMG recruitment of > 50 per cent; evidence of an adequate level of intrarectal pressure (> 50 cmH2O) on straining; and presence of defective evacuation.

[Electromyography and functional analytic findings in obstructive disorders of defecation. A contribution to the differentiation of neurogenic and myogenic sphincter damage]

The aim of this study was to get further information about functional results in patients with outlet obstruction. We investigated 27 patients (age between 42 and 74 years) by electromyography (EMG), manometry and radiology with contrast-solution. The electromyography, a dynamic investigation method, allows the differentiation between neuronal and muscular malfunctions of the voluntary controlled pelvis muscles. Patients with outlet obstruction should be divided into three groups by EMG diagnosis: One group with neuronal alterations, another group with muscular alterations and one group with neuro-muscular alterations. We obtained marked statistical differences between patients with neuronal or muscular malfunctions in the mean amplitude, the turns per second and the integration of the mean amplitude compared to the control group (14 patients). Patients with only neuronal alterations showed furthermore statistically significant distinctions of the action potential duration from control, whereas the data of patients with muscular malfunctions were significantly different from control in the peak amplitude of the action potentials. 77% of all investigated patients were not able to relax the pelvis muscles during defecation.