Rectal Evacuation Research Articles

Does surgical repair of a rectocele improve rectal emptying?

This study was undertaken to assess results of surgical repair of rectocele and to identify possible determinants of outcome from patient's history and preoperative defecography. Another aim was to evaluate how surgery affects rectal evacuation. Thirty-four women with constipation and rectal emptying difficulties underwent surgery with a transanal technique. A preoperative defecography was performed in each patient. They were followed up after a median of 10 (range, 2-60) months with a questionnaire (n = 34) and a defecography (n = 31). Computer-based image analysis of defecographies was used to evaluate rectal evacuation. In 27 patients (79 percent), the result of surgery was good with subjectively improved emptying. The need for vaginal or perineal digitation preoperatively was related to a good result (P < 0.05), whereas a previous hysterectomy (P < 0.01) and a large rectal area on defecography (P < 0.01) related to a poor result. Preoperative use of enemas, motor stimulants, or several types of laxatives also related to a poor outcome (P < 0.05). Surgical treatment resulted in reduction of the rectocele (P < 0.001), an elevated position of the anorectal junction (P < 0.05), and improved rectal evacuation on defecographies (P < 0.001). Surgical repair reduces the size of the rectocele and improves rectal emptying. These changes are accompanied by a symptomatic improvement in the majority of patients. Preoperative patient data and defecography may help in selecting patients for surgery.

Is digitation associated with proctographic abnormality?

Constipated patients referred for evacuation proctography were questioned as to the need for digital manoeuvres to assist evacuation, to determine the frequency of digitation, and to investigate whether any proctographic feature was associated with this symptom. Seventy one percent of patients interviewed admitted to digitation. Proctographic findings in 20 constipated patients who digitated per vagina and 20 who digitated per anum were compared to 20 who did not. There was no significant difference between groups with respect to pelvic floor descent, anal canal width or any anrectal angle measurement. Rectocoele depth and area were significantly greater in patients who digitated per vagina, compared to the other two groups. Evacuation time was prolonged and a proctographic diagnosis of anismus more frequent, in patients who digitated per anum. Anal digitation is associated with prolonged evacuation, suggesting a proctographic diagnosis of anismus and vaginal digitation to assist rectal evacuation is significantly associated with large anterior rectocoele.

Enterocele revealed by simultaneous evacuation proctography and peritoneography: does "defecation block" exist?

Pelvic floor weakness may allow prolapse of the bowel into the rectogenital space, forming an enterocele. Enteroceles are believed to obstruct defecation by rectal compression and are therefore considered an abnormal finding on evacuation proctography. With a technique combine evacuation proctography and peritoneography, we prospectively studied constipated patients to reveal the pelvic peritoneal recesses during evacuation and to determine if enterocele actually impairs rectal emptying. Fifty constipated patients were studied prospectively, Using 20 ml of water-soluble contrast medium, we performed peritoneography, then evacuation protography with 120 ml of intrarectal paste. Lateral evacuation and posteroanterior stress views were analyzed by computerized video capture. Anatomic features and functional measurements of rectal emptying were noted. Posteroanterior views were compared with views in 31 subjects undergoing peritoneography for investigation of groin pain. Technical failure in three patients left 47 for analysis. A deep rectogenital pouch was seen in 36 patients (77%). Of these, 12 (58%) contained viscera that formed an enterocele, but the remaining 15 patients (42%) showed no visceral filling. Most pouches were apparent only during straining (31 cases, 86%). Peritoneal descent was greater than in controls (p < .0001), of whom only three had small rectogenital pouches. Patients with enterocele were compared with those who had a rectogenital pouch but no visceral filling and those who had no pouch. Standard anatomic measurements by evacuation proctography were not significantly different, but patients with enterocele evacuated more rapidly (p = .008) and completely (p = .021) than did the other two groups. Combined evacuation proctography and peritoneography is a new technique to diagnose pelvic hernias that occur during evacuation. This technique has shown that a deep rectogenital pouch is common in constipated patients and that just over half such pouches fill with viscera. However, because an enterocele does not impair rectal evacuation, this proctographic finding should be interpreted with caution.

Megacystis — microcolon — intestinal hypoperistalsis syndrome

Two non-related female neonates with the megacystis-microcolon-intestinal hypoperistalsis syndrome are described. One presented with a family history of a similar condition. In one child no intestinal peristalsis was observed, while in the other decreased peristalsis with occasional rectal evacuation occurred. Both had fatal outcomes. These two cases demonstrate the wide variation in the clinical course of this rare and fatal syndrome.

Sigmoidorectal junction reflex: Role in the defecation mechanism

The presence of a sphincter at the rectosigmoid junction (RSJ) is debated. This investigation studies the presence or absence of a sphincter and its possible role in sigmoid colon storage and rectal evacuation. Eighteen healthy volunteers (10 males, 8 females) with a mean age of 36.6 ± 14.8 years (range 21–53) were studied. The pressure response of the sigmoid colon, RSJ, and rectum to sigmoid and rectal distension, respectively, was determined before and after anesthetizing either the sigmoid colon or the rectum. The RSJ length was evaluated by the station pull-through technique. Sigmoid distension with balloon volumes of up to 80.6 ± 4.4 ml of H2O effected no sigmoid, RSJ, or rectal pressure changes (P > 0.05). At a mean sigmoid distension of 88.6 ± 4.1 ml of H2O, the sigmoid colon showed a significant pressure increase (P < 0.001), a RSJ pressure decrease (P < 0.05), and insignificant pressure changes in the rectum (P > 0.05); the balloon was dispelled into the rectum. Rectal distension of 94.6 ± 5.8 ml of H2O produced rectal (P < 0.001) and RSJ (P < 0.05) pressure increases. Distension of the anesthetized sigmoid and rectum did not produce pressure changes in the RSJ (P > 0.05). This study demonstrated a high pressure zone at the RSJ of 3.8 ± 0.7 cm in length. This suggests that the RSJ might act as a functional sphincter. It opens reflexly upon sigmoid contraction, by a reflex we call “rectosigmoid inhibitory reflex,” and closes upon rectal contraction, a reflex we call “rectosigmoid excitatory reflex.” The former allows the stored feces in the sigmoid colon to pass to the rectum, and the latter reflex prevents stool reflux to the sigmoid upon rectal contraction. © 1996 Wiley-Liss, Inc.

Results of colectomy for severe slow transit constipation

This study assesses the outcome of a standardized operation performed by two surgeons for severe idiopathic slow transit constipation that was resistant to laxative treatment. Fifty-nine consecutive patients, 4 men and 55 women, with a mean age of 42.3 years, underwent colectomy with ileorectal anastomosis. Slow colonic transit was demonstrated in each case. Fifty-two patients were available for follow-up, with median time to follow-up being 42 (range, 3-81) months. Median bowel frequency was 4 per 24 hours. Sixty-nine percent had four or less bowel movements daily. Ten percent used antidiarrheal medication regularly. One patient had a stoma for recurrent severe constipation. Mean continence score was 1.8 (on a scale of 0-20); six patients were incontinent, and four of these six had normal preoperative anal manometry. Fourteen patients (27 percent) had difficulty with rectal evacuation. Preoperative defecating proctography was a poor predictor of postoperative evacuation difficulties. Twenty-seven patients (52 percent) had persisting abdominal pain, but there was a significant improvement in the degree of pain (P <0.00001). Forty-seven patients (90 percent) were satisfied with the outcome of the operation (and would elect to have it done again). Dissatisfied patients had recurrent constipation or diarrhea and incontinence. Colectomy with ileorectal anastomosis produces a satisfactory functional outcome in the majority of patients undergoing surgery for severe constipation with proven slow colonic transit.

Scintigraphic assessment of colonic function during defaecation.

The aim of this study was to develop a method by which rectal and colonic activity could be examined during defaecation under physiological conditions, in order to evaluate whether the colon plays a role in defaecation. Subjects presented to the Nuclear Medicine department on the day following ingestion of oral In-111 labelled DTPA, when they developed the normal urge to defaecate. Defaecation took place in a private room while dynamic scintigraphy of the rectum and colon was recorded. Fourteen subjects were studied (8 normal subjects, 4 with constipation, 2 with irritable bowel syndrome). In 13 subjects the left colon was visualized during defaecation and emptying was clearly observed in 12. The right colon was visualised in 11 subjects and emptying was seen in 7. Mean percentage segmental evacuation was right colon 20%, left colon 32% and rectum 66%. Colonic emptying occurs during defaecation, which is not a process of rectal evacuation only. This has implications for the understanding of the pathophysiology of obstructed defaecation.

Sacral root stimulation for controlled defecation.

Selective rectal or sphincter neurostimulation aiming at controlled defecation was performed in 10 dogs. While the dogs were under anesthesia, the rectal and rectal neck pressures, balloon expulsion as well as external anal sphincter (EAS) response to stimulation of the second sacral ventral nerve root (S2) and its autonomic and somatic branches were determined. Each of these nerves was stimulated separately using bipolar platinum cuff electrodes. S2 stimulation resulted in rectal and rectal neck pressure elevation as well as increase of EMG activity of EAS without balloon expulsion. Autonomic branch stimulation effected rectal pressure increase and balloon expulsion, while somatic branch stimulation caused increase of rectal neck pressure and EAS EMG activity with no balloon expulsion. S2 stimulation with somatic branch transection produced rectal pressure elevation and balloon expulsion. In contrast to rectal pressure, the rectal neck pressure increased with increasing stimulus frequency. In conclusion, rectal evacuation and sphincteric control could be induced by selective sacral root electrostimulation: S2 stimulation with transection of the somatic branch for the former and pudendal branch stimulation for the latter.

Functional obstructive defaecation

Objective: To study patients with obstructive defaecation to determine quantitatively its pathophysiology and homogeneity. Design: Twenty-two patients with obstructive defaecation were studied by isotope proctography and by conventional methods for quantitative analysis of the pathophysiological factors involved. Methods: Examination of the patients included ano-rectal manometry, the rectal balloon expulsion test, pelvic floor electromyography and isotope proctography. Eleven asymptomatic subjects were studied for comparison. Results: Pelvic floor electromyography revealed increased 'straining electromyographic activity' in all patients (P< 0.001). Patients with obstructive defaecation had impaired rectal sensation and were unable to perform a complete rectal evacuation (54% rectal evacuation) on isotope proctography. The defaecation time was prolonged and was associated with a reduced defaecation rate. Simultaneous recording of intrarectal pressures and external anal sphincter (EAS) electromyography during proctography revealed increased intrarectal pressure (P<0.0001) and EAS electromyographic voltage (P<0.01) during evacuation. The anorectal angles correlated with the pelvic floor movement and the anismus index. The anismus index in these patients correlated with the intrarectal pressure (P<0.02). No increase in the electromyographic voltage of the EAS was observed in any of the control subjects who successfully performed rectal balloon expulsion. Conclusion: Obstructive defaecation is a multifactórial condition involving derangements of rectal sensation and abnormal activity of the pelvic floor and anal sphincter musculature; its homogeneity is affected by the duration of the process.

Quantification of evacuation proctography

This study was designed to determine if evacuation proctography provides a clinically acceptable estimate of the time and completeness of rectal evacuation. Rectodynamics, using a weight transducer and chart recorder to quantify the weight and rate of contrast expelled, was combined with evacuation proctography to assess agreement between the evacuation times recorded and the weight of contrast expelled compared with the lateral area change on proctography. Mean difference of evacuation times measured by the techniques was 0.1 seconds and the standard deviation of the differences was 1.9 seconds with 95 percent agreement limits of +/- 3.9 seconds. The mean difference between the percentage of contrast evacuated by weight and the change in rectal area on proctography was 4.3 percent. The standard deviation of the differences was 11.9 percent with 95 percent agreement limits of -19.5 percent and +28.1 percent. Evacuation proctography provides a valid estimation of the time and completeness of rectal evacuation.

Obstructive defaecation and slow transit constipation: the proctographic parameters

Twenty-two patients with functional obstructive defaecation were compared with seven patients with slow transit constipation using isotope proctography. The obstructive defaecation patients were unable to perform a complete rectal evacuation (% of the activity evacuated: 54%). The defaecation time in this group was prolonged (120 s) with a lower defaecation rate (0.5%/s) compared with the slow transit constipation subjects (32 s and 1.8%/s). The anorectal angle (ARA) on straining did not change in the obstructive defaecation patients but became more obtuse in the slow transit constipation subjects (P < 0.02). The pelvic floor (PF) descent on straining and evacuation was greater in obstructive defaecation patients compared with the slow transit constipation ones (P < 0.01). Obstructive defaecation is characterised by prolonged defaecation and reduced defaecation rate compared with slow transit constipation. Obstructive defaecation patients present with more acute ARAs on straining, and abnormal perineal descent in contrast to the slow transit constipation ones.

Continent colonic conduit for rectal evacuation in severe constipation

We describe a new operation for the treatment of rectal evacuatory disorders: a continent colonic conduit, incorporating an intussuscepted valve, was constructed from the sigmoid colon. Intubation of the conduit allowed irrigation and evacuation of the distal colon and rectum. Initially all 10 patients reported a reduction in time taken and the discomfort involved in completing evacuation. The number of stools passed per week increased in 9 out of 10 patients, from a median of 1 5 (range 0·25-7) to a median of 7 (range 3-7) postoperatively. Subsequently, 3 patients developed complications, 2 of whom required conversion to an ileostomy. Overall, the colonic conduit procedure was successful in treating the rectal evacuatory disorder in 7 patients, failed in 2, and 1 patient has a temporary defunctioning ileostomy. The procedure is a relatively simple surgical alternative for the treatment of a condition which is often resistant to conservative measures.

SURGERY FOR SEVERE CONSTIPATION: THE USE OF RADIOISOTOPE TRANSIT SCAN AND BARIUM EVACUATION PROCTOGRAPHY IN PATIENT SELECTION

Nineteen women aged 19-64 years (median 38) with intractable constipation were assessed by Indium-111 DTPA colonic transit scan and barium evacuation proctogram. Patients were classified as having an isolated (I) or predominant disorder of colonic transit (II), a mixed disorder of colonic transit and rectal evacuation (III), a predominant disorder of rectal evacuation (IV) or normal colorectal emptying (V). Twelve patients fell into categories I and II and were considered suitable for surgery. Three responded to further vigorous aperient therapy and nine (32-55 years, median 38) underwent subtotal colectomy with ileorectal anastomosis at the level of the sacral promontory. Two patients required re-operation for suspected anastomotic leak. One patient required readmission on two occasions for small bowel obstruction. Follow up has been 2-21 months (median 16). Eight of the nine patients no longer take oral aperients. Eight patients have a satisfactory stool frequency of 2-8 per 24 h; the other patient has an ileostomy and incapacitating postprandial abdominal pain. Abdominal pain is troublesome in two other patients. Two patients require antidiarrhoeal therapy but none experience faecal incontinence. In severely constipated patients with a proven disorder of colonic transit but normal or near normal rectal evacuation subtotal colectomy provides excellent symptomatic relief.

Bowel dysfunction: a pathogenic factor in uterovaginal prolapse and urinary stress incontinence

To investigate the aetiological importance of bowel dysfunction in patients with uterovaginal prolapse and urinary stress incontinence. Observational study using a questionnaire about obstetric history and bowel function, and anorectal physiological studies. Physiology unit and gynaecological outpatients departments of two teaching hospitals. Twenty-three women with uterovaginal prolapse (mean age 57 years), 23 women with urinary stress incontinence (mean age 52 years) and 27 control women (mean age 52 years). There was no statistically significant difference between the three groups in their parity, age or birthweight of their children. However, straining at stool as a young adult prior to the development of urogynaecological symptoms was significantly more common in women with uterovaginal prolapse (61% vs 4%, P < 0.001) and women with urinary stress incontinence (30% vs 4%, P < 0.05), compared with controls. A bowel frequency of less than twice per week as a young adult was also more common in women with uterovaginal prolapse than in control women (48% vs 8%, P < 0.001). At the time of consultation, 95% of the women with uterovaginal prolapse were constipated, compared with only 11% of control women. Many of these women also needed to digitate to achieve rectal evacuation. Compared with controls, women with uterovaginal prolapse had a prolonged pudendal nerve terminal motor latency (1.9 ms vs 2.2 ms, respectively, P = 0.003). Women with stress incontinence of urine had a normal pudendal nerve latency (2.0 ms). Other tests of anorectal function were normal. Constipation, in addition to obstetric history, appears to be an important factor in the pathogenesis of uterovaginal prolapse.

Scintigraphic defecography: quantitative and dynamic assessment of anorectal function.

Conventional assessment of anorectal function with defecating videoproctography is semiquantitative and the high radiation exposure precludes prolonged or repeated testing. The aim of this study was to develop a dynamic scintigraphic method of assessing anorectal function. Fourteen patients with fecal incontinence, 18 patients with chronic constipation, and 8 control subjects were assessed by scintigraphic defecography. This involves introduction of a technetium-99m-radiolabeled artificial stool into the rectum of the subject and acquisition of gamma camera images during evacuation. Mean evacuation rate was 2.8 percent/second in incontinent patients and 0.9 percent/second in constipated patients (P < 0.001). The mean anorectal angles were 136 degrees and 133 degrees, respectively. There were 18 cases of pelvic floor descent and 6 rectoceles. Scintigraphic defecography provides quantitative information on rectal evacuation. Anorectal angle and pelvic floor movement can be examined. The radiation dose to pelvic organs is significantly less than with videoproctography. We believe that scintigraphic defecography is the investigation of choice for objective and dynamic assessment of anorectal function.

Quantification of evacuation proctography

PURPOSE: This study was designed to determine if evacuation proctography provides a clinically acceptable estimate of the time and completeness of rectal evacuation. METHODS: Rectodynamics, using a weight transducer and chart recorder to quantify the weight and rate of contrast expelled, was combined with evacuation proctography to assess agreement between the evacuation times recorded and the weight of contrast expelled compared with the lateral area change on proctography. RESULTS: Mean difference of evacuation times measured by the techniques was 0.1 seconds and the standard deviation of the differences was 1.9 seconds with 95 percent agreement limits of ±3.9 seconds. The mean difference between the percentage of contrast evacuated by weight and the change in rectal area on proctography was 4.3 percent. The standard deviation of the differences was 11.9 percent with 95 percent agreement limits of −19.5 percent and+28.1 percent. CONCLUSION: Evacuation proctography provides a valid estimation of the time and completeness of rectal evacuation.

Evaluation of isotope proctography in constipated subjects

Twelve patients with longstanding constipation were examined by isotope proctography. Radio-labelled potato mash was inserted rectally to provoke the urge to defaecate and expulsive manoeuvres were recorded using a Gamma-camera. The method illustrated dynamic alterations in the anorectal angles (ARA) which became more acute on 'squeezing', less so on coughing and more obtuse on straining, and maximally so on evacuation. The pelvic floor (PF) movements were consistently upwards on squeezing, less so on coughing, downwards on straining, and maximally so on evacuation. A useful addition was the measurement of the completeness of evacuation and the time involved. The results were comparable to radiological videoproctography (P < 0.01), but the isotope method gave greater discrimination for both ARA and PF movement changes. It also allowed correlations to be made between the pelvic floor descent (P < 0.05) and anorectal angle changes (P < 0.01) with rectal evacuation.

Combined anorectal manometry and defecography in 50 consecutive adults with fecal incontinence.

Fifty consecutive patients presenting with fecal incontinence were evaluated prospectively with anorectal manometry, defecography, and other tests of anorectal function to assess the clinical utility of defecography in fecal incontinence. Leakage of contrast at rest and failure to narrow the anorectal angle with pelvic squeezing were specific but not sensitive predictors of decreased sphincter pressures as determined by manometry. Thus, after manometry, defecography provided no additional information regarding sphincter strength. Retention of contrast in large rectoceles or incomplete rectal evacuation at defecography had excellent correlation with the presence of clinical symptoms of outlet obstruction constipation (present concurrently with incontinence) and indicated an etiology of outlet obstruction symptoms. Defecography may provide useful information in incontinent patients with outlet obstruction constipation symptoms but has little additive value to anorectal manometry in incontinent patients without such symptoms.

The small intestine and colon: scintigraphic quantitation of motility in health and disease

Radioisotopes allow accurate quantitation of the pattern and effectiveness of the transit of chyme through the small and large intestines. Abnormalities of small bowel transit can be demonstrated in patients with the irritable bowel syndrome, and patients with chronic idiopathic intestinal pseudo-obstruction due to either a visceral myopathy or neuropathy. In the colon, radioisotopic studies of transit have demonstrated the site of delayed transit in some severely constipated patients. In patients with these disorders of transit, functional studies may influence the choice of medical or surgical therapy although there are few prospective studies which have established their worth in this context. Radioisotope studies can also be utilised to study the effectiveness of delivery of drugs to the small and large bowel, and to study the adequacy of rectal evacuation in patients with a defaecatory disturbance. The low radiation dose and possibility of frequent observations make radioisotope studies valuable for clinical and research studies in functional gastrointestinal disorders.

Relationship between clinical symptoms of anal incontinence and the results of anorectal manometry

The aim of this work was to analyze clinical symptoms in light of anorectal manometry results. We compared the frequency of clinical symptoms in relation with the presence or absence of functional anomalies. Using this methodology, the following relationships may be suggested: the need to wear a pad, with a decreased resting pressure at the upper part of the anal canal; the inability to delay rectal evacuation, with decreased anal voluntary contraction; interference of incontinence with social activities, with decreased duration of anal voluntary contraction; urinary symptoms, with an increased threshold volume of rectal distention needed to elicit the rectoanal inhibitory reflex; and complete rectal prolapse, with reduced length of the anal canal.