Normalization of substance P levels in rectal mucosa of patients with faecal incontinence treated successfully by sacral nerve stimulation

Background

Sacral nerve stimulation (SNS) may improve faecal incontinence by modulating rectal sensation. This study measured changes in the peripheral expression of various neural epitopes in response to SNS.

Methods

Rectal mucosal biopsies were taken from 12 patients before and after temporary SNS, and from ten responders at 90 days after permanent stimulation. Sections were immunostained for substance P, transient receptor potential vanilloid (TRPV) 1, vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP). Levels were compared with those in nine continent controls.

Results

Baseline levels of percentage area immunoreactivities of substance P (median 0·51 (95 per cent confidence interval 0·31 to 0·73) versus 0·13 (0·07 to 0·27) per cent; P < 0·001) and TRPV1 (0·76 (0·41 to 1·11) versus 0·09 (0·04 to 0·14) per cent; P < 0·001), but not of VIP (1·26 (0·37 to 2·15) versus 1·28 (0·39 to 2·17); P = 0·943), were significantly greater than in controls. Successful SNS resulted in a significant decrease in substance P immunostaining after temporary (0·15 (0·06 to 0·51) per cent; P = 0·051) and permanent (0·17 (0 to 0·46) per cent; P = 0·051) stimulation. Immunoreactivity of TRPV1, VIP, CGRP and neural markers showed no qualitative change.

Conclusion

Patients with faecal incontinence demonstrate normalization of raised rectal mucosal substance P levels following successful SNS.

In patients with slow transit constipation, the pattern of colonic transit delay does not differentiate between those with and without impaired rectal evacuation

BACKGROUND

Severe constipation may be subclassified on the basis of speed of colonic transit and efficacy of rectal evacuation. It is hypothesized that rectal evacuatory disorder (RED) may be associated with a secondary transit delay.

OBJECTIVES

To determine whether scintigraphy can discriminate between slow transit constipation (STC) with or without coexistent RED on the basis of progression of isotope throughout the colon and by analyses of specific regions of interest.

METHODS

One hundred ninety-six patients with STC (radio-opaque marker study) were subclassified according to results of proctography into those with a RED (STC-RED N = 30) or normal (STC-ONLY N = 41) evacuation. Patients subsequently underwent colonic scintigraphy. Distribution of generalized or left-sided patterns of colonic transit was assessed. Severities of transit delay and regional transit at specific time points were also evaluated.

RESULTS

Time-activity curves and severity of global transit delay were similar between groups as were the incidences of generalized and left-sided patterns of delay. Percentage of radioisotope retention in the right colon at 18 h was higher for the STC-ONLY group (P < 0.05), but this was poorly discriminative. No differences were observed for the percentage of radioisotope retained in the left colon at later scans.

CONCLUSIONS

Global and regional assessment of colonic transit by scintigraphy failed to discriminate between patients with STC with or without coexistent RED. Thus, RED is not associated with a specific pattern of transit delay and scintigraphy alone cannot predict the presence or absence of RED, knowledge of which is important for management.

Rectal hyposensitivity: evaluation of anal sensation in female patients with refractory constipation with and without faecal incontinence

Rectal hyposensitivity (RH) is commonly found in patients with intractable constipation, faecal incontinence or both. Anal sensation may also be blunted in these conditions. We aimed to determine whether RH is associated with anal hyposensitivity, which may reflect a combined viscero-somatic neuropathy. One hundred and fifty-eight female patients with chronic constipation underwent physiological investigation including rectal sensation to volumetric balloon distension, and distal anal mucosal sensation to electrostimulation. Data were also obtained from 32 healthy female volunteers. Anal mucosal electrosensory thresholds were significantly higher in patients compared with volunteers (median: 2.4 mA, range: 0.4-19.6 vs 1.1 mA, range: 0.1-4.2, respectively), although the patient group was older (P < 0.0001), but there was no difference (P = 0.572) in the incidence of blunted anal sensation between those with normal rectal sensation (n = 113, 20% abnormal) and RH (n = 45, 24% abnormal). Irrespective of rectal sensory function, there was a strong association between symptom duration (P = 0.012) and anal hyposensitivity. One-fifth of constipated female patients had evidence of diminished anal sensation. However, the presence of RH was not associated with an increased frequency of anal hyposensitivity, thereby suggesting that different aetiopathogenic mechanisms underlie the development of anal and rectal hyposensitivity. Further studies in carefully selected, homogenous patient populations are necessary to elucidate these mechanisms.

Faecal incontinence (Br J Surg 2007; 94: 134–144)

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A novel technique to identify patients with megarectum

PURPOSE

Traditional methods of identifying patients with persistent dilation of the rectum, or megarectum, are associated with inherent methodologic limitations. The purpose of this study was to use a barostat to establish criteria for the diagnosis of megarectum and to assess rectal diameter during isobaric (barostat) and volumetric (barium contrast) distention protocols in constipated patients with megarectum on anorectal manometry.

METHODS

During fluoroscopic screening, rectal diameter was measured at minimum distending pressure of the rectum, achieved using a barostat. It was also measured during evacuation proctography (volumetric distention). Having established a normal range in 25 healthy volunteers, 30 constipated patients with evidence of megarectum on anorectal manometry (elevated maximum tolerable volume on latex balloon distention) were studied. A further 10 constipated patients without evidence of megarectum were studied (normal rectum).

RESULTS

Megarectum was diagnosed when the rectal diameter was greater than 6.3 cm at minimum distending pressure. Rectal diameter at minimum distending pressure was increased in 20 patients (67 percent) with megarectum on anorectal manometry, but was normal in the remaining 10 patients (33 percent) and all patients with a normal rectum on anorectal manometry. Rectal diameter was increased at evacuation proctography in only 15 patients (50 percent) with evidence of megarectum on anorectal manometry.

CONCLUSIONS

The prevalence of megarectum is overestimated and underestimated when rectal diameter is assessed using anorectal manometry and contrast studies, respectively. Controlled (pressure-based) distention combined with fluoroscopic imaging allowed accurate identification of patients with megarectum on the basis of a rectal diameter greater than 6.3 cm at the minimum distention pressure. Measurement of rectal diameter at minimum distention pressure may be useful in those patients with an elevated maximum tolerable volume on anorectal manometry when surgery is being contemplated.

Unilateral pudendal neuropathy is common in patients with fecal incontinence

PURPOSE

Pudendal neuropathy and fecal incontinence frequently coexist; however, the contribution of neuropathy is unknown. The pudendal nerve innervates the external anal sphincter muscle, anal canal skin, and coordinates reflex pathways. Lateral dominance or a dominantly innervating nerve and its subsequent damage may have major implications in the etiology and treatment of fecal incontinence. This study was designed to establish the prevalence of pudendal neuropathy, in particular a unilateral one, and to examine the impact on anorectal function.

METHODS

A total of 923 patients (745 females; mean age, 52 (range, 17-92) years) with fecal incontinence were studied using endoanal ultrasonography, anorectal manometry, rectal sensation, and pudendal nerve terminal motor latencies.

RESULTS

A total of 520 patients (56 percent) demonstrated a pudendal neuropathy, which was unilateral in 38 percent (351 patients; 169 right-sided, 182 left-sided). Neuropathy, whether it was bilateral (bilateral vs. normal; 56 (range, 7-154) cm H2O) vs. 67 (range, 5-215) cm H2O; P < 0.01) or unilateral (unilateral vs. normal; 61 (range, 0-271) cm H2O vs. 67 (range, 5-215) cm H2O; P = 0.04) was associated with reduced anal resting tone. This also was seen with respect to squeeze increments (bilateral vs. normal; 34 (range, 0-207) cm H2O vs. 52 (range, 0-378) cm H2O; P < 0.001, unilateral vs. normal; 41 (range, 0-214) cm H2O vs. 52 (range, 0-378) cm H2O; P < 0.01). In those with intact sphincters, unilateral neuropathy was associated with reduced squeeze increments (unilateral vs. normal; 60 (range, 10-286) cm H2O vs. 69 (range, 7-323) cm H2O; P = 0.01) but no significant reduction in resting pressures. There was no association between pudendal neuropathy and abnormal rectal sensitivity.

CONCLUSIONS

Unilateral pudendal neuropathy is a common abnormality in individuals with fecal incontinence and is significantly associated with both attenuated resting pressures and squeeze increments. Although there are limitations in the interpretation of pudendal nerve terminal motor latencies, this study demonstrates that further exploration of the concept of lateral dominance is needed.

Multimedia article. External pelvic rectal suspension (the express procedure) for internal rectal prolapse, with or without concomitant rectocele repair: a video demonstration

PURPOSE

Internal rectal prolapse has been proposed as a cause of symptomatic rectal evacuatory dysfunction. Abdominal rectopexy, the standard surgical approach, has significant attendant risk and does not address any concomitant rectocele. This video was designed to demonstrate a novel surgical method that uses porcine collagen implants (Permacol), designed to correct internal rectal prolapse, with or without rectocele.

INCLUSION CRITERIA

severe rectal evacuatory dysfunction refractory to maximal conservative therapy and full-thickness internal rectal prolapse impeding rectal emptying on defecography with or without associated functional rectocoele; normal colonic transit. Patients undergo comprehensive preoperative and postoperative symptomatic assessment and anorectal physiologic testing, including defecography. A crescenteric perineal skin incision allows development of the rectovaginal/rectoprostatic plane to Denonvilliers fascia, with rectal mobilization. A curved tunneller inserted via the perineal wound is guided retropubically to emerge through suprapubic wounds created on each side. Permacol T-strips are sutured to the anterolateral rectal wall bilaterally, upward traction exerted, and the stem of each T-strip is sutured to the suprapubic periosteum, suspending the rectum. Concomitant rectocele is repaired using a Permacol patch in the rectovaginal plane.

RESULTS

Short-term results for the "Express" are encouraging with improvement in evacuatory and prolapse symptoms and concomitant anatomic improvement at defecography.

CONCLUSIONS

This procedure promises to be an effective technique for managing patients with refractory evacuatory dysfunction secondary to internal rectal prolapse, with or without rectocele.

The nocturnal jejunal migrating motor complex: defining normal ranges by study of 51 healthy adult volunteers and meta-analysis

Interdigestive human small bowel motility is characterized by the migrating motor complex (MMC). The aims of this study were to: (i) establish the normal range of variables of the nocturnal jejunal MMC and (ii) incorporate these data in a subsequent meta-analysis. Eighty-one recordings were performed by prolonged (24 h) ambulatory manometry in 51 subjects in two centres. Quantitative analysis was undertaken of 419 Phase III and 332 Phase II episodes. Adjusted mean values of seven variables were calculated using a mixed-effects model. Meta-analysis of pooled published data to generate a reliable 95% reference range was also performed. Adjusted mean values and confidence intervals are presented for all seven variables. Intrasubject variances were large in comparison with intersubject. Meta-analysis of 19 studies (356 pooled patients) meeting inclusion criteria produced wide reference ranges. At least five such ranges are useful for the detection of abnormality in the individual. This is the largest study of normal volunteers presented to date, with ranges for many variables produced using appropriate statistical methodology. A model for definition of abnormality has been proposed. We recommend that these data may be used by investigators in this field as a complement to other existing indicators of small bowel dysmotility.

Rectal hyposensitivity

Rectal hyposensitivity (RH) relates to a diminished perception of rectal distension that is diagnosed during anorectal physiologic investigation. There have been few direct studies of this physiologic abnormality, and its contribution to the development of functional bowel disorders has been relatively neglected. However, it appears to be common in patients with such disorders, being most prevalent in patients with functional constipation with or without fecal incontinence. Indeed, it may be important in the etiology of symptoms in certain patients, given that it is the only "apparent" identifiable abnormality on physiologic testing. Currently, it is usually diagnosed on the basis of elevated sensory threshold volumes during balloon distension in clinical practice, although such a diagnosis may be susceptible to misinterpretation in the presence of altered rectal wall properties, and thus it is uncertain whether a diagnosis of RH reflects true impairment of afferent nerve function. Furthermore, the etiology of RH is unclear, although there is limited evidence to support the role of pelvic nerve injury and abnormal toilet behavior. The optimum treatment of patients with RH is yet to be established. The majority are managed symptomatically, although "sensory-retraining biofeedback" appears to be the most effective treatment, at least in the short term, and is associated with objective improvement in the rectal sensory function. Currently, fundamental questions relating to the contribution of this physiologic abnormality to the development of functional bowel disorders remain unanswered. Acknowledgment of the potential importance of RH is thus required by clinicians and researchers to determine its relevance.

Upper limits on a stochastic background of gravitational waves

The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.

Rectal sensorimotor dysfunction in patients with urge faecal incontinence: evidence from prolonged manometric studies

BACKGROUND AND AIMS

Although external anal sphincter dysfunction is the major cause of urge faecal incontinence, approximately 50% of such patients have evidence of rectal hypersensitivity and report exaggerated stool frequency and urgency. The contribution of rectosigmoid contractile activity to the pathophysiology of this condition is unclear, and thus the relations between symptoms, rectal sensation, and rectosigmoid motor function were investigated.

METHODS

Fifty two consecutive patients with urge faecal incontinence, referred to a tertiary surgical centre, and 24 volunteers, underwent comprehensive anorectal physiological investigation, including prolonged rectosigmoid manometry. Patients were classified on the basis of balloon distension thresholds into those with rectal hypersensitivity (n = 27) and those with normal rectal sensation (n = 25). Automated quantitative analysis of overall rectosigmoid contractile activities and, specifically, high amplitude contractions and rectal motor complex activity was performed.

RESULTS

External anal sphincter dysfunction was similar in both patient groups. Overall, phasic activity and high amplitude contraction frequency were greater, and rectal motor complex variables significantly altered, in those with rectal hypersensitivity. Symptoms, more prevalent in the rectal hypersensitivity group, were also more often associated with rectosigmoid contractile events. For individuals, reduced compliance and increased rectal motor complex frequency were only observed in patients with rectal hypersensitivity.

CONCLUSIONS

We have identified a subset of patients with urge faecal incontinence-namely, those with rectal hypersensitivity-who demonstrated increased symptoms, enhanced perception, reduced compliance, and exaggerated rectosigmoid motor activity. Comprehensive assessment of rectosigmoid sensorimotor function, in addition to evaluation of anal function, should be considered in the investigation of patients with urge faecal incontinence.

Rectal intussusception: a study of rectal biomechanics and visceroperception

OBJECTIVES

Rectal intussusception (RI) is a significant cause of morbidity amongst those with a rectal evacuatory disorder. The pathophysiology is unknown, but may involve abnormal biomechanics of the rectal wall similar to that previously demonstrated in patients with overt rectal prolapse (RP). Using an electromechanical barostat, this study aimed to investigate the biomechanics and visceroperception of the rectal wall in patients with RI.

METHODS

Twenty consecutive patients (12 females, median age 46 yr (range 24-66)) with symptomatic, full-thickness RI were studied. Patients underwent assessment of rectal compliance, visceroperception, adaptive response to isobaric distension at urge threshold, and assessment of the postprandial response. Results were compared with those obtained in 28 asymptomatic volunteers, 10 with RI (6 females, median age 29 yr (range 21-36)) and 18 (9 females, median age 33 yr (range 21-62)) without.

RESULTS

In the absence of the clinical finding of solitary rectal ulcer syndrome (SRUS), patients with symptomatic RI have normal rectal wall biomechanics, as do asymptomatic volunteers with RI (p < 0.05). Patients with the clinical finding of SRUS had reduced compliance and adaptation. In all three groups, there was a linear relationship between rectal pressure and visceroperception. The postprandial contractile response was similar between groups.

CONCLUSIONS

Patients with RI have normal rectal wall biomechanics. This is in contrast to patients with RP, and suggests that while they may represent different stages of the same disease process, they are physiologically distinct. In patients with RI and SRUS, rectal wall inflammation and fibrosis, perhaps arising secondary to the intussusception, may explain the physiological changes observed.

Contribution of the pudendal nerve to sensation of the distal rectum

Background

Anal and rectal sensory mechanisms and pudendal nerve function are important in the control of faecal continence. The contribution of the pudendal nerve to sensation of the distal rectum was investigated.

Methods

Heat thresholds in the anal canal, distal and mid rectum were measured using a specially designed thermoprobe. Rectal sensory threshold volumes were measured using the balloon distension method. Needle electrodes were inserted into the external anal sphincter. Pudendal nerve block was performed through a perineal approach, and completeness assessed by loss of electromyographic activity. Heat and rectal volume thresholds were measured again following unilateral and bilateral pudendal nerve block.

Results

The technique was successful in four of six volunteers. Bilateral pudendal nerve block produced complete anaesthesia to heat in the anal canal (P = 0·029), but had no effect on heat thresholds in the distal or mid rectum. Rectal sensory threshold volumes were also unaffected by pudendal nerve anaesthesia.

Conclusion

Anal canal sensation is subserved by the pudendal nerve, but this nerve is not essential to nociceptive sensory mechanisms in the distal or mid rectum. The transition between visceral control mechanisms in the lower rectum and somatic mechanisms in the anal canal may have functional importance in the initiation of defaecation and the maintenance of continence.

Rectal intussusception in symptomatic patients is different from that in asymptomatic volunteers

Background

Rectal intussusception is a common finding at evacuation proctography in both symptomatic and asymptomatic individuals. Little information exists, however, as to whether intussusception morphology differs between patients with evacuatory dysfunction and healthy volunteers.

Methods

Thirty patients (19 women; median age 44 (range 21–76) years) with disordered rectal evacuation, in whom an isolated intussusception was seen on proctography, were studied. Various morphological parameters were measured, and compared with those from 11 asymptomatic controls (six women; median age 30 (range 24–38) years) found, from 31 volunteers, to have rectal intussusception. Intussusceptum thickness greater than 3 mm was designated as full thickness. Intussuscepta impeding evacuation were deemed to be occluding.

Results

Twenty-two patients had full-thickness intussusception, compared with two controls (P = 0·003). Intussusceptum thickness was significantly greater in the symptomatic group (anterior component: P = 0·004; posterior: P = 0·011). Twenty patients in the symptomatic group, but only three subjects in the control group, had a mechanically occluding intussusception (P = 0·043), although only three patients demonstrated evacuatory dynamics outside the normal range.

Conclusion

Rectal intussusception in patients with evacuatory dysfunction is more advanced morphologically than that seen in asymptomatic controls; it is predominantly full thickness in patients and mucosal in controls. However, caution is required when selecting patients for intervention based solely on radiological findings.

Limits on gravitational-wave emission from selected pulsars using LIGO data

We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.

Systematic review of surgical options for idiopathic megarectum and megacolon

OBJECTIVE

A subgroup of patients with intractable constipation has persistent dilatation of the bowel, which in the absence of an organic cause is termed idiopathic megabowel (IMB). The aim of this systematic review was to evaluate the published outcome data of surgical procedures for IMB in adults.

METHODS

Electronic searches of the MEDLINE (PubMed) database, Cochrane Library, EMBase, and Science Citation Index were performed. Only peer-reviewed articles of surgery for IMB published in the English language were evaluated. Studies of all surgical procedures were included, providing they were performed on 3 or more patients, and overall success rates were documented. Studies were critically appraised in terms of design and methodology, inclusion criteria, success, mortality and morbidity rates, and functional outcomes.

RESULTS

A total of 27 suitable studies were identified, all evidence was low quality obtained from case series, and there were no comparative studies. The studies involved small numbers of patients (median 12, range 3-50), without long-term follow-up (median 3 years, range 0.5-7). Inclusion of subjects, methods of data acquisition, and reporting of outcomes were extremely variable. Subtotal colectomy was successful in 71.1% (0%-100%) but was associated with significant morbidity related to bowel obstruction (14.5%, range 0%-29%). Segmental resection was successful in 48.4% (12.5%-100%), and recurrent symptoms were common (23.8%). Rectal procedures achieved a successful outcome in 71% to 87% of patients. Proctectomy, the Duhamel, and pull-through procedures were associated with significant mortality (3%-25%) and morbidity (6%-29%). Vertical reduction rectoplasty (VRR) offered promising short-term success (83%). Pelvic-floor procedures were associated with poor outcomes. A stoma provided a safe alternative but was only effective in 65% of cases.

CONCLUSIONS

Outcome data of surgery for IMB must be interpreted with extreme caution due to limitations of included studies. Recommendations based on firm evidence cannot be given, although colectomy appears to be the optimum procedure in patients with a nondilated rectum, restorative proctocolectomy the most suitable in those with dilatation of the colon and rectum, and VRR in those patients with dilatation confined to the rectum. Appropriately designed studies are required to make valid comparisons of the different procedures available.

Medium-term results of vertical reduction rectoplasty and sigmoid colectomy for idiopathic megarectum

Background

Vertical reduction rectoplasty (VRR) was devised specifically to address the physiological abnormalities present in the rectum of patients with idiopathic megarectum (IMR). This study evaluated the medium-term clinical and physiological results of VRR.

Methods

VRR and sigmoid colectomy was performed in ten patients with IMR and constipation (six women). Patients were evaluated before and a median of 60 (range 28–74) months after surgery by assessment of symptoms using scoring systems and anorectal physiological measurements. Independent, detailed postoperative evaluation of rectal diameter, compliance, and sensory and evacuatory function was performed.

Results

There were no deaths or late complications. Symptoms recurred necessitating permanent ileostomy formation in two patients. Median (range) constipation scores improved from 22 (18–27) before to 10 (0–24) after surgery (P = 0·016). Median (range) bowel frequency increased from 1·5 (0·2–7) to 7 (0·5–21) per week (P = 0·016). Rectal diameter, compliance and sensory function were normal in seven of eight patients after surgery. Evacuatory function and colonic transit were each normalized in two of eight patients after VRR.

Conclusion

VRR corrected rectal diameter, compliance and sensory function in most patients, and clinical benefit was sustained in the medium term. The procedure was associated with a low morbidity, and no mortality and should be considered in the surgical management of IMR.

Rectal intussusception: characterization of symptomatology

PURPOSE

Rectal intussusception is a common finding at evacuation proctography; however, its significance has been debated. This study was designed to characterize clinically and physiologically a large group of patients with rectal intussusception and test the hypothesis that certain symptoms are predictive of this finding on evacuation proctography.

METHODS

A total of 896 patients underwent evacuation proctography from which three groups were identified: those with isolated rectal intussusception (n = 125), those with isolated rectocele (n = 100), and those with both abnormalities (n = 152). Multivariate analyses were used to identify symptoms predictive of findings by evacuation proctography.

RESULTS

The symptoms of anorectal pain and prolapse were highly predictive of the finding of isolated intussusception over rectocele (odds ratio, 3.6, P = 0.006; odds ratio, 4.9, P < 0.001) or combined intussusception and rectocele (odds ratio, 2.9, P = 0.02; odds ratio, 2.4, P = 0.03). The symptom of "toilet revisiting" was associated with the finding of rectoanal intussusception (odds ratio, 3.55, P = 0.04). Although patients with mechanically obstructing intussuscepta evacuated slower and less completely (P < 0.001) than those with nonobstructing intussuscepta, no symptom was predictive of this finding on evacuation proctography.

CONCLUSIONS

Although certain symptoms are predictive of the finding of rectal intussusception, there is a wide overlap with symptoms of rectocele, another common cause of evacuatory dysfunction. Furthermore, the observation that "obstruction to evacuation" made on proctography had no impact on the incidence of evacuatory symptoms suggests that beyond simply demonstrating the presence of an intussusception, analysis of proctography and subclassifying intussusception morphology seems of little clinical significance, and selection for surgical intervention on the basis of proctographic findings may be illogical.

EXternal Pelvic REctal SuSpension (Express procedure) for rectal intussusception, with and without rectocele repair

Background

The results of conventional treatment for rectal intussusception and rectocele are unpredictable. The aim was to develop a less invasive surgical approach and to evaluate outcome in selected patients.

Methods

Seventeen patients (13 women; median age 47 (range 20–67) years) with rectal evacuatory dysfunction and rectal intussusception, 13 of whom had a rectocele, were selected. The intussusception was corrected by external pelvic suspension of the rectum, using collagen strips attached to the rectal wall and pubis. The rectocele was repaired with a collagen patch. Patients were assessed before and 6 months after surgery by symptom and quality of life questionnaires, anorectal physiological investigation and proctography, and were followed up for a median of 12 months.

Results

Sepsis requiring exploration occurred in two patients but there was no extrusion or need to remove the collagen. Of the 15 patients assessed after surgery, total symptom scores were significantly decreased (P &lt; 0·001) and quality of life scores improved (P &lt; 0·001). Proctographically, the degree of intussusception was improved in ten patients; six patients had normal postoperative proctograms. The rectocele was reduced in size in all patients, and was not demonstrable in eight.

Conclusion

An effective procedure for rectal intussusception and rectocele has been developed in a selected group of patients with marked evacuatory symptoms.

External pelvic rectal suspension (the Express procedure) for full-thickness rectal prolapse: evolution of a new technique

OBJECTIVE

The Délorme's operation for rectal prolapse is a safe procedure but has a high recurrence rate. We aimed to develop an operation akin to it, but designed to reduce this deficit.

PATIENTS AND METHODS

Thirty-one consecutive patients with rectal prolapse were included in the study. Initially, a conventional Délorme's procedure was performed and sutures or strips of Gore-Tex were attached circumferentially to the apex of the prolapse, tunneled subcutaneously, and anchored to the external surface of the pelvis. Subsequently, the procedure was modified. Acellular porcine collagen strips were used and buried within the apex without plication of the denuded rectal musculature. Patients were formally assessed preoperatively and four months postoperatively by symptom and quality of life questionnaires and subsequently by regular clinical review.

RESULTS

In the Gore-Tex group (N = 11; males:females = 10:1; mean age, 61 years) three patients underwent suture repair and eight had strip fixation. All suture repairs developed sepsis and one patient had a recurrence. Seven of the strip fixations (88 percent) developed sepsis that resulted in implant extrusion. There was one full-thickness and one mucosal recurrence after a median follow-up of 25 months. In the collagen group (N = 20; males:females = 2:18; mean age, 63 years), sepsis occurred in four patients, requiring surgical intervention in one patient (5 percent) (cf Gore-Tex group, P = 0.002). There was one mucosal and three full-thickness (15 percent) recurrences after a median follow-up of 14 months (cf Gore-Tex group, P = not significant). Significant improvements in symptom and quality of life scores were recorded in both groups at four months.

CONCLUSION

A new, minimally invasive perineal procedure for rectal prolapse has been developed and initial data testify to its relative safety provided collagen is used. It remains to be seen whether long-term recurrence rates will be lower than those of conventional perineal procedures.

Rectal hyposensitivity: a disorder of the rectal wall or the afferent pathway? An assessment using the barostat

OBJECTIVES

Rectal hyposensitivity (RH) relates to a diminished perception of rectal distension. Diagnosis on the basis of abnormal threshold volumes on balloon distension alone may be inaccurate due to the influence of differing rectal wall properties. The aim of this study was to investigate whether RH was actually due to impaired afferent nerve function or whether it could be secondary to abnormalities of the rectal wall.

METHODS

A total of 50 patients were referred consecutively to a tertiary referral unit for physiologic assessment of constipation (Rome II criteria), 25 of whom had associated fecal incontinence. Thirty patients had RH (elevated threshold volumes on latex balloon distension), and 20 patients had normal rectal sensation (NS). Results were compared with those obtained in 20 healthy volunteers (HV). All subjects underwent standard anorectal physiologic investigation, and assessment of rectal compliance, adaptive response to isobaric distension at urge threshold, and postprandial rectal response, using an electromechanical barostat.

RESULTS

Mean rectal compliance was significantly elevated in patients with RH compared to NS and HV (p < 0.001). However, 16 patients with RH (53%) had normal compliance. Intensity of the urge to defecate during random phasic isobaric distensions was significantly reduced in patients with RH compared to NS and HV (p < 0.001). The adaptive response at urge threshold was reduced in patients with RH compared to NS and HV (p < 0.001), although spontaneous adaptation at operating pressure was similar in all three groups studied (p= 0.3). Postprandially, responses were similar between groups.

CONCLUSIONS

In patients found to have RH on simple balloon distension, impaired perception of rectal distension may be partly explained in one subgroup by abnormal rectal compliance. However, a second subgroup exists with normal rectal wall properties, suggestive of a true impairment of the afferent pathway. The barostat has an important role in the identification of these subgroups of patients.

Rectal hypersensitivity worsens stool frequency, urgency, and lifestyle in patients with urge fecal incontinence

PURPOSE

Rectal sensory mechanisms are important in the maintenance of fecal continence. Approximately 50 percent of patients with urge incontinence have lowered rectal sensory threshold volumes (rectal hypersensitivity) on balloon distention. Rectal hypersensitivity may underlie the heightened perception of rectal filling; however, its impact on fecal urgency and incontinence is unknown. This study was designed to investigate the impact of rectal hypersensitivity in patients with urge fecal incontinence.

METHODS

Prospective and retrospective audit review of all patients (n = 258) with an intact native rectum referred to a tertiary colorectal surgical center for physiologic investigation of urge fecal incontinence during a 7.5-year period. Patients with urge fecal incontinence who had undergone pelvic radiotherapy (n = 9) or rectal prolapse (n = 6) were excluded.

RESULTS

A total of 108 of 243 patients (44 percent) were found to have rectal hypersensitivity. The incidence of anal sphincter dysfunction was equal (90 percent) among those with or without rectal hypersensitivity. Patients with urge fecal incontinence and rectal hypersensitivity had increased stool frequency (P < 0.0001), reported greater use of pads (P = 0.003), and lifestyle restrictions (P = 0.0007) compared with those with normal rectal sensation, but had similar frequencies of incontinent episodes.

CONCLUSIONS

Urge fecal incontinence relates primarily to external anal sphincter dysfunction, but in patients with urge fecal incontinence, rectal hypersensitivity exacerbates fecal urgency, and this should be considered in the management and surgical decision in patients who present with fecal incontinence.