Rectal Compliance Research Articles

Tu1747 Altered Rectal Tone and Compliance and Hyposensitivity for Non-Noxious Stimuli in Patients With Fecal Incontinence After Anorectal Surgery

Tu1747 Altered Rectal Tone and Compliance and Hyposensitivity for Non-Noxious Stimuli in Patients With Fecal Incontinence After Anorectal Surgery

Tu2018 Rectal Compliance, Acclimation, and Bowel Symptoms in Women With Irritable Bowel Syndrome (IBS)

Tu2018 Rectal Compliance, Acclimation, and Bowel Symptoms in Women With Irritable Bowel Syndrome (IBS)

Alternative procedure to shorten rectal barostat procedure for the assessment of rectal compliance and visceral perception: a feasibility study

BackgroundBarostat methodology is widely used for assessing visceral perception. Different barostat protocols are described with respect to the measurement of rectal compliance and visceral perception. The choice of protocols affects the duration, which is normally 60–90 min, and accuracy of the procedure. This study aimed to shorten the procedure by using the semi-random distension protocol for both compliance and visceral perception measurement and a correction based on rectal capacity (RC) instead of minimal distension pressure (MDP).MethodsTwelve irritable bowel syndrome (IBS) patients (7 females) and 11 healthy controls (8 females) underwent a barostat procedure. Compliance was determined during both a staircase distension and a semi-random protocol. Visceral perception data were compared as a function of pressure or relative volume, corrected for MDP or RC, respectively.ResultsCompliance measurement using the semi-random protocol instead of the staircase distension protocol resulted in an overestimation in healthy volunteers, but not in IBS patients. The overall conclusion that IBS patients had a lower compliance compared to controls was not different between protocols. Data presentation of the visceral perception scores as a function of corrected volume instead of pressures corrected for MDP did not alter the conclusion that sensation scores in IBS patients were higher as compared to healthy controls.ConclusionsThis study showed that barostat procedures may be shortened by approximately 20 min, without losing the ability to discriminate between healthy controls and IBS patients. A correction for RC instead of MDP may improve the accuracy of the procedure.Electronic supplementary materialThe online version of this article (doi:10.1007/s00535-012-0543-x) contains supplementary material, which is available to authorized users.

Anorectal Anomalies in Adults-Laparoscopic Management and Review of Literature

Anorectal malformations (ARMs) are one of the most common congenital anomalies dealt by surgeons. The reported incidence of ARMs range between 1:3,300 and 1:5,000 live births. These defects are invariably detected and treated in infancy or early childhood. There is a group of patients among these who have fistulous external opening from the rectum. These may not present in child hood and may continue to live with fecal incontinence till adult hood. One of such anomalies is rectovaginal fistulas which comprises of only 4% of all anomalies. Delayed management in such cases increases surgical and functional complications. Traditionally high and intermediate anorectal anomalies are treated by posterior sagittal anorectoplasty (PSARP). This involves cutting of sphincter muscles in the midline and then placement of rectum in the sphincter complex. The continence results of this operation are less than ideal. Laparoscopically assisted anorectal pull-through (LAARP) has potential advantage of precise placement of the rectum inside the sphincter complex without dividing and weakening the muscles, diminished soft tissue scarring around the rectum leading to improved rectal compliance. Three adult female patients with ARMs were managed through LAARP procedure. It involves dissection around rectum, identification and ligation of fistula tract, creation of neoanus and pull through of rectum into neoanus. Results-Continence was good in all our patients which they regained after 3 to 4days of surgery. On follow up which ranged from 6months to 2years all were passing well formed stools 1-2 times a day and have symmetric anal contraction with strong squeeze on digital rectal examination. Conclusion-LAARP offers an excellent option to the patients of ARM over conventional posterior sagittal anorectal approach because if its theoretical advantages of early recovery and better continence. Long term followup is needed to substantiate these results.

Increased rectal wall stiffness after prostate radiotherapy: relation with fecal urgency

Late anorectal toxicity is a frequent adverse event of external beam radiotherapy (EBRT) for prostate cancer. The pathophysiology of anorectal toxicity remains unknown, but we speculate that rectal distensibility is impaired due to fibrosis. Our goal was to determine whether EBRT induces changes of rectal distensibility as measured by an electronic barostat and to explore whether anorectal complaints are related to specific changes of anorectal function. Thirty-two men, irradiated for localized prostate carcinoma, underwent barostat measurements, anorectal manometry, and completed a questionnaire prior to and 1 year after radiotherapy. The primary outcome measure was rectal distensibility in response to stepwise isobaric distensions. In addition, we assessed sensory thresholds, anal pressures, and anorectal complaints. External beam radiotherapy reduced maximal rectal capacity (227 ± 14 mL vs 277 ± 15 mL; P < 0.001), area under the pressure-volume curve (3212 ± 352 mL mmHg vs 3969 ± 413 mL mmHg; P < 0.005), and rectal compliance (15.7 ± 1.2 mL mmHg(-1) vs 17.6 ± 0.9 mL mmHg(-1) ; P = 0.12). Sensory pressure thresholds did not significantly change. Sixteen of the 32 patients (50%) had one or more anorectal complaints. Patients with urgency (n = 10) had a more reduced anal squeeze and maximum pressure (decrease 29 ± 11 mmHg vs 1 ± 7 mmHg; P < 0.05 and 31 ± 12 mmHg vs 2 ± 8 mmHg; P < 0.05 respectively) compared with patients without complaints, indicating a deteriorated external anal sphincter function. Irradiation for prostate cancer leads to reduced rectal distensibility. In patients with urgency symptoms, anal sphincter function was also impaired.

The effects of sildenafil on rectal sensitivity and tone in patients with the irritable bowel syndrome

Visceral tone supposedly affects gut sensitivity in irritable bowel syndrome (IBS). Sildenafil increases nitric oxide and influences visceral compliance. To evaluate the effects of sildenafil tone inhibition on rectal sensitivity. Eight controls and 21 IBS patients (Rome II) were enrolled in a double-blind study, after dosing with placebo or sildenafil (50 mg p.o.). Thresholds for first sensation, first desire to defecate, pain and supraliminar pain were the sensory endpoints, measured with a barostat and 600-mL rectal bag. Pain (100-mm VAS) and depression-anxiety (Hamilton questionnaire) were scored. Irritable bowel syndrome rectal compliance and sensory-endpoint thresholds were similar to controls. Five IBS patients had pain threshold lower than controls 95% confidence interval (hypersensitive). Depression score was greater in IBS than controls (11.9 ± 1.3 vs. 6.3 ± 2.5, P = 0.036). In IBS, pain intensity was nonsignificantly higher (37.6 ± 5.3 mm vs. 23.4 ± 8.5 mm, P = 0.064) and supraliminar pain intensity was greater (45.6 ± 5.4 mm vs. 25.9 ± 5.1 mm, P = 0.044) than controls. IBS rectal relaxation increased volume (155.4 ± 41.3 mL vs. 118.8 ± 47.7 mL, P = 0.004) and tension (193.1 ± 118.6 mmHg mL(-1) vs. 133.2 ± 98.1 mmHg mL(-1) , P = 0.019) for triggering first desire to defecate but not for other perceptions. Sildenafil increased volume for both first desire to defecate and pain in the hypersensitive IBS patients. Sildenafil increased rectal compliance only in diarrhoea-IBS. Mixed-IBS obtained higher anxiety (12.9 ± 1.3 vs. 5.9 ± 3.1, P < 0.05) and depression scores (13.9 ± 1.9 vs. 6.3 ± 2.5, P < 0.05) and reported more intense supraliminar pain (53.6 ± 9.8 mm vs. 25.9 ± 5.1 mm, P < 0.05) than controls. Rectal relaxation following dosing with sildenafil 50 mg increased the first desire to defecate threshold in IBS as a whole, but decreased pain only in the hypersensitive subset. Mixed-IBS presented higher supraliminar pain and anxiety-depression scores.

Effects of vaginal hysterectomy on anorectal sensorimotor functions--a prospective study.

While bowel and bladder dysfunction are recognized consequences of a radical hysterectomy, the effects of a simple hysterectomy on anorectal sensorimotor functions, particularly rectal sensation, vary among studies and the effects on rectal compliance remain unknown. Our aims were to prospectively evaluate anorectal sensorimotor functions before and after a hysterectomy. Anal pressures, rectal compliance, capacity, sensation, and bowel symptoms were assessed before, at 2 months, and at 1 year after a simple vaginal hysterectomy for benign indications in 19 patients. Rectal staircase (0-44 mmHg, 4-mmHg steps), ramp (0-200 mL at 50, 200 and 600 mL min(-1)) and phasic distentions (8, 16, and 24 mmHg above operating pressure) were performed. Anal resting (63 ± 4 before, 56 ± 4 mmHg after) and squeeze pressures (124 ± 12 before, 124 ± 12 mmHg after), rectal compliance and capacity (285 ± 12 before, 290 ± 11 mL 1 year after), and perception of phasic distentions were not different before vs after a hysterectomy. Sensory thresholds for first sensation and the desire to defecate were also not different, but pressure and volume thresholds for urgency were somewhat greater (Hazard ratio = 0.7, 95% CI [0.5, 1.0]) 1 year after (vs before) a hysterectomy. Rectal pressures were higher (P < 0.0001) during fast compared with slow ramp distention; this rate effect was greater at 1 year after a hysterectomy, particularly at 100 mL (P = 0.04). A simple vaginal hysterectomy has relatively modest effects (i.e., somewhat reduced rectal urgency and increased stiffness during rapid distention) on rectal sensorimotor functions.

Fecal Incontinence in Systemic Sclerosis Is Secondary to Neuropathy

Systemic sclerosis (SSc) is a chronic multi-system autoimmune disorder with gastrointestinal tract (GIT) involvement in up to 90% of patients and anorectal involvement occurs in up to 50% of patients. The pathogenesis of gastrointestinal abnormalities may be both myogenic and neurogenic. We aimed to identify which anorectal physiological abnormalities correlate with clinical symptoms and thus understand the pathophysiology of anorectal involvement in SSc. In total, 44 SSc patients (24 symptomatic (Sx) (fecal incontinence) and 20 asymptomatic (ASx)) and 20 incontinent controls (ICs) were studied. Patients underwent anorectal manometry, rectal mucosal blood flow (RMBF), rectal compliance (barostat), and rectoanal inhibitory reflex assessment (RAIR). Anal squeeze pressure was lower in the IC group compared with both the ASx and Sx groups (IC: 46.95 (30-63.9)) vs. ASx: 104.6 (81-128.3) vs. (Sx: 121.4 (101.3-141.6); P < 0.05). Resting pressure was lower in the IC group. RMBF and rectal compliance did not differ between groups. Anal, but not rectal, sensory threshold, was significantly attenuated in Sx patients (Sx: 10.4 (8.8-11.4) vs. ASx: 6.7 (5.7-7.7) vs. IC: 8.5 (6.5-10.4); P < 0.05). There was a positive correlation between anal sensory thresholds and incontinence score in SSc patients (r = 0.54; P < 0.05). RAIR was absent in 11/24 Sx patients but only in 2/20 ASx and in 1/20 IC patients. Fecal incontinence in SSc is related to neuropathy as suggested by absent RAIR and higher anal sensory threshold and is related less so to sphincter atrophy and rectal fibrosis.

Does meal ingestion enhance sensitivity of visceroperception assessment in irritable bowel syndrome?

Visceral hypersensitivity is frequently observed in irritable bowel syndrome (IBS). Previous studies have shown that administration of a meal can aggravate symptoms or increase visceroperception in IBS patients. We investigated whether meal ingestion could increase the sensitivity of the barostat procedure for the detection of visceral hypersensitivity in IBS patients. Seventy-one IBS patients and 30 healthy controls (HC) were included in the study. All subjects underwent a barostat procedure under fasted and postprandial conditions to measure visceroperception. Urge, discomfort, and pain were scored on a visual analog scale. Furthermore, percentages of hypersensitive IBS patients and HC were calculated and dynamic rectal compliance was assessed. In IBS patients, urge, discomfort, and pain scores were significantly increased postprandially vs the fasted state. The HC showed increased scores for urge and pain only. Rectal dynamic compliance remained unaltered in both groups. Postprandial hypersensitivity percentages did not significantly differ vs the fasted state in IBS patients, nor in HC. Postprandial barostat measurement enhances visceroperception in IBS but has no added value to detect visceral hypersensitivity in individual IBS patients.

Temporary Sacral Nerve Stimulation Alters Rectal Sensory Function: A Physiological Study

The indications for sacral nerve stimulation are increasing, but the mechanism remains poorly understood. This study aimed to examine the effect of sacral nerve stimulation on rectal compliance and rectal sensory function. This was a prospective study. This study took place at a university teaching hospital. Twenty-three consecutive consenting patients (22 female; median age, 49 y) undergoing temporary sacral nerve stimulation for fecal incontinence were prospectively studied. Clinical response was assessed by the use of bowel diaries and Wexner scores. Anal manometry, rectal compliance, volume and pressure thresholds to rectal distension (barostat), and rectal Doppler mucosal blood flow were measured before and at the end of stimulation. Sixteen patients (70%) had a favorable clinical response. Median anal squeeze pressures increased with stimulation from 40 (range, 6-156) cmH2O to 64 (range, 16-243) cmH2O. Median rectal compliance did not significantly change with stimulation (prestimulation: 11.5 (range, 7.9-21.8) mL/mmHg, poststimulation: 12.4 (range, 6.2-22) mL/mmHg, P = .941). Rectal wall pressures associated with urge (baseline: 15.4 (range, 11-26.7) mmHg, poststimulation: 19 (range, 11.1-42.7) mmHg, P = .054) and maximal tolerated thresholds (baseline: 21.6 (8.5-31.9) mmHg, poststimulation: 27.1 (14.3-43.3) mmHg, P = .023) significantly increased after stimulation. Rectal Doppler mucosal blood flow did not significantly change with stimulation (baseline: 125.8 (69.9-346.8), poststimulation: 112.4 (50.2-404.1), P = .735). Changes in anal resting pressure and rectal wall pressures with stimulation were evident only in responders; however, changes in anal squeeze pressures were evident in both responders and nonresponders. The study reports results following short-term stimulation in a small but homogenous group of patients. A larger long-term study will follow. Temporary sacral nerve stimulation does not change rectal compliance, but is associated with significant changes to the pressure thresholds of rectal distension. This, together with the observation that outcome is not related to sphincter integrity, supports the hypothesis of an afferent-mediated mechanism of action.

Anorectal Motility and Sensation Abnormalities and Its Correlation with Anorectal Symptoms in Patients with Systemic Sclerosis: A Preliminary Study

Gastrointestinal (GI) hypomotility and symptoms are common in Scleroderma (SSc) patients yet so far uncorrelated. Eight SSc patients and matched controls were queried about their GI dysmotility symptoms and quality of life (QoL) and underwent anorectal motility and sensory tests. Specific scoring systems were developed for anorectal symptoms and anorectal dysmotility. We found that (1) the SSc patients showed low QoL and marked overall GI symptoms. The most common anorectal symptom was incomplete bowel movement (50%). (2) Compared to normal controls, SSc patients showed impaired anorectal pressures, sensations, and rectal compliance (P ≤ .01 for each). (3) The anorectal motility/sensation abnormality score was robustly correlated with the total anorectal symptom score (r s = .78, P = .02). In conclusion, scleroderma patients have impaired anorectal motor and sensory functions, and the abnormality score of these anorectal functions is correlated with the total anorectal symptoms score. These scoring systems may assist clinicians in predicting dysmotility based on patient symptoms.

Symptoms in patients with ulcerative colitis in remission are associated with visceral hypersensitivity and mast cell activity

Objective. Patients with ulcerative colitis in remission (UCR) frequently report irritable bowel syndrome (IBS)-like symptoms. Recent studies have pointed to the role of mast cells in mediating visceral hypersensitivity in IBS. We hypothesized that visceral hypersensitivity is frequently present in patients with UCR and is related to the quantity and activity of mast cells in the sigmoid mucosa. Material and methods. A group of 17 controls and 19 patients with UCR were studied. Rectal compliance and perception were measured by electronic barostat. Sigmoid biopsies were taken to quantify the amount of mast cells, degranulating mast cells and mast cells in close proximity to mucosal nerve endings. Results. Visceroperception significantly increased in UCR (p < 0.05) versus controls. Rectal perception correlated positively with IBS-like symptoms in UCR (r = 0.969; p < 0.05). The amount of mucosal mast cells (per 100 crypts) was significantly increased in UCR versus controls: 228 ± 20 versus 163 ± 18 (p < 0.05). In the UCR patients a higher percentage of mucosal mast cells was in close proximity to nerve endings (58 ± 4 vs. 38 ± 3% in controls; p < 0.05) or was degranulating (40 ± 7 vs. 16 ± 4% in controls; p < 0.05). There was a significant but weak correlation between quantity of mucosal mast cells and pain perception (r = 0.32; p < 0.05). Conclusion. Rectal hypersensitivity is associated with mucosal presence and activation of mast cells and with IBS-like symptoms in patients with UCR.

Effect of the α2δ ligand, pregabalin, on colonic sensory and motor functions in healthy adults

Pregabalin, an α2δ ligand, is used clinically to treat somatic pain. A prior study suggested that pregabalin reduces distension-induced pain while increasing rectal compliance. We aimed to quantify effects of pregabalin on colonic sensory and motor functions and assess relationships between sensory effects and colonic compliance. We conducted a randomized, double-blind, placebo-controlled, parallel-group study of a single oral administration of 75 or 200 mg of pregabalin in 62 healthy adults (aged 18-75 yr). Subjects underwent left colon intubation. We assessed "stress-arousal symptoms", compliance, sensation thresholds, sensation ratings averaged over four levels of distension, fasting and postprandial colonic tone, and phasic motility index (MI). Analysis of covariance (adjusted for age, sex, body mass index, and corresponding predrug response) and proportional hazard models were used. There were no clinically important differences among treatment groups for demographics, predrug compliance, tone, MI, and sensation. Treatment was associated with reduced energy and increased drowsiness but no change in tension or relaxation. Sensation ratings averaged over the four distension levels were lower for gas sensation [overall effect P = 0.14, P = 0.05 (pregabalin 200 mg vs. placebo)] and for pain sensation [overall effect P = 0.12, P = 0.04 (pregabalin 200 mg vs. placebo)]. The magnitude of the effect of 200 mg of pregabalin relative to placebo is on average a 25% reduction of both gas and pain sensation ratings. Pregabalin did not significantly affect colonic compliance, sensation thresholds, colonic fasting tone, and MI. Thus 200 mg of pregabalin reduces gas and pain sensation and should be tested in patients with colonic pain.

Impact of Sleep Dysfunction on Anorectal Motility in Healthy Humans

Background/AimsSleep dysfunction is associated with altered gastrointestinal function and subsequently exacerbations of gastrointestinal problems. We aimed to investigate whether sleep dysfunction would influence anorectal motility as determined by anorectal manometry. The effect of anxiety on anorectal motility was also determined.MethodsA total of 24 healthy volunteers underwent anorectal manometry. The anorectal parameters included resting and squeeze sphincter pressure, sensory thresholds in response to balloon distension, sphincter length, rectal compliance, and rectoanal inhibitory reflex. Sleep dysfunction was subjectively assessed by using Pittsburgh Sleep Quality Index (PSQI). Anxiety was assessed by the application of the State-Trait Anxiety Inventory questionnaire.ResultsThere were sixteen subjects without sleep dysfunction (7 women; mean age, 22 years) and eight subjects with sleep dysfunction (2 women; mean age, 22 years). There was no group difference in the volume threshold for rectoanal inhibitory reflux, rectal compliance or sphincter length (P = NS). Anal sphincter pressure did not differ between the groups (P = NS). The rectal sensitivity for different levels of stimulation did not differ between the groups (P = NS). Sleep quality as determined by PSQI correlated with rectal compliance (r = 0.66, P = 0.007). Although there was no differences in any manometric parameters between subjects with and without anxiety, the anxiety score correlated with rectal compliance (r = 0.57, P = 0.003).ConclusionsDespite a positive association between rectal compliance and the level of subjective sleep or anxiety, sleep dysfunction did not apparently affect most of anorectal function in healthy subjects, nor did anxiety.

Disturbed Sleep and Disturbed Bowel Functions: Implications for Constipation in Healthy Individuals

In 1993, Goldsmith and Levin brought to our attention that disturbed sleep could have an adverse effect on bowel functions.1 They employed a diary to record the relationship between sleep disturbance and bowel symptoms in subjects with irritable bowel syndrome (IBS). They found that morning IBS symptoms were increased when the quality of sleep was poor the night before, and decreased when subjects had slept better. These findings were replicated by a study of women with IBS which found that sleep disturbance one night predicted gastrointestinal symptoms the following day.2 Neither study analysed individual bowel symptoms. While disruption of biologic rhythms secondary to night shift work has been associated with gastrointestinal symptoms, these studies have not specifically examined the effects on bowel habits.3 To study the effects of disturbed sleep on bowel functions, we recruited healthy female full time nurses working in a tertiary hospital to keep a bowel and sleep diary for 2 weeks. Of 60 nurses working regular hours during the day only, we found constipation symptoms in 8 (13%), while in 58 nurses working on rotating shifts involving working 4-8 night shifts per month, we found constipation symptoms in 14 (24%).4 Using multivariate analysis, we showed that sleep disturbance, decreased well-being, anxiety, somatic pain and age were all independent predictors of bowel disturbance. Based on these observations, we hypothesized that disturbed sleep could affect bowel functions in healthy individuals. In this journal, Liu et al, from Taiwan, have studied anorectal physiology in university students, comparing those with good and poor sleep quality as measured by the Pittsburgh Sleep Quality Index (PSQI) score. In this cohort, IBS was rigorously excluded by applying the Rome III criteria. In addition, subjects with fibromyalgia were also excluded. Thus, the focus of this study is on defecation function, rather than on visceral or somatic pain perception. Not surprisingly, they did not find any differences in sensitivity to rectal distension between good and poor sleepers. Rather, they found that PSQI scores correlated positively with rectal compliance. What this means is that the poorer the sleep, the greater the rectal compliance. Rectal compliance is the measure of the capacity of the rectal wall to stretch upon pressure stimulus. Increased rectal compliance has been proposed to be a contributing mechanism underlying constipation. The implication is that poor sleep may predispose a previously healthy individual to constipation. Sleep disturbance as a potential pathogenic factor in constipation has not been previously explored. The limitation of the present study was that the assessment of sleep quality was retrospective. In order to explore the role of sleep disturbance in constipation, we would need to study in a prospective manner the effects of sleep deprivation on anorectal physiology, and correlate these changes with the quality of defecation. This approach was employed by Bergin and Read; 8 healthy male volunteers were confined in the investigation unit and kept awake for 35 hours, while an equal number were allowed to return home to sleep overnight.5 Anorectal manometry and rectal distension studies were carried out at the start of the study, and repeated after 24 hours, in both groups. In the sleep deprived group, sensitivity to rapid rectal distension stimulus increased, while in the control group, no significant change was observed. This observation suggests that sleep deprivation could predispose to visceral hypersensitivity which has been implicated as a pathogenic mechanism for abdominal pain in IBS. Unfortunately, this study did not examine in detail the effects of sleep on constipation. The authors reported no differences in the number of bowel movements between the 2 groups, but the changes in stool consistency and feeling of incomplete evacuation were not assessed. However, if we examine their data carefully, in their sleep deprived group there was actually a trend for an increase in rectal compliance that was not discerned in the control group. Irregular working hours is no longer just a fact of life for doctors and nurses. With globalisation, workers in more and more industries will have to accept work schedules that will result in shorter sleep duration and a change to their usual sleep routine. Thus, it is important that more, and better planned, studies are conducted to define the effects of sleep disturbances and chronobiological factors on bowel functions.

Gender Differences in Motility of the Large and Small Intestine in Patients With IBS

Background: Visceral hypersensitivity, and altered gastrointestinal motility and secretion, are considered to be key pathophysiological factors in irritable bowel syndrome (IBS), and of great importance for symptom generation. The symptom pattern differs between female and male IBS patients , with more severe abdominal pain, bloating and constipation in females (Khatai et al. DDW 2010). Whether this can be explained by gender differences in pathophysiological alterations is incompletely understood. Aim: To evaluate potential gender differences in small intestinal motility and secretion, colonic motility and rectal sensorimotor function in patients with IBS. Methods: We included 36 male and 36 female IBS patients, matched for age (mean age 39 (20-64) years), who fulfilled the ROME II criteria. All patients underwent investigations to assess colonic motility (colonic transit time using radiopaque markers), small intestinal motility and secretion (antroduodenojejunal manometry with jejunal transmural potential difference (PD) measurement in the fasting state (3h) and after meal intake (1h)) and rectal sensorimotor function (rectal balloon distensions before and after meal intake; 800kcal; 60% fat). Results: Colonic transit time differed between female and male IBS patients, with slower transit in females (2.1±1.3 (mean±SD) vs. 1.2±0.8 days; p<0.0001). Differences were also found in the small intestinal motility with slower propagation velocity of phase III in females (8.7±4.5 vs. 15±9.4 cm/min; p<0.01), and a tendency towards shorter duration of phase III in females (p<0.1). The motility indices in the jejunum also tended to be lower in female versus male IBS patients, but this only reached statistical significance in the fasting state (last 30 min of phase II) (3310±1040 vs. 4510±2730 mmHg x sec; p<0.05). No gender differences were seen in PD measurements in the small intestine, reflecting chloride secretion, or in rectal compliance, tone or sensitivity. Conclusion: We have demonstrated gender differences in small and large intestinal motility in IBS patients, but not in small intestinal secretion or rectal sensorimotor function. These findings are of potential importance for observed differences in the symptom pattern between male and female IBS patients.

To improve the “target” of transanal hemorrhoidal dearterialization

Sir, We read with interest the paper by Toh et al. [1]. This study was carried out with the critical attitude of those who want to improve a surgical treatment that is very effective but can still be improved. Our comments about the study results concern the ‘‘functional anatomy’’ of the lower rectum. Actually, in addition to the exact number of terminal branches of the higher rectal arteries, a fundamental factor in this surgical approach is the correct understanding of the topography of these branches and their relationship with the rectal wall. Hemorrhoidal dearterialization with transanal hemorrhoidal dearterialization (THD) ensures an excellent control of rectal bleeding, and in most cases, the resolution of prolapse thanks to a ‘‘tailored mucopexy’’. The complex vascular network of the ‘‘corpus cavernosum recti’’ is the key to perfecting this therapeutic approach. According to our experience, there are always more than three (usually six) terminal branches of hemorrhoidal arteries to be ligated [2]. The target of therapy should be the point at which the arteries enter the submucosa of the low rectum, just before supplying blood to the ‘‘corpus cavernosum recti’’ [3]. In this way, an extraparietal arterial ligation can be avoided, and action can be taken right where the arterial hyperflow could have the greatest effect on the hemorrhoids. Use of Doppler-guided THD allows a detailed identification of the arteries and a rigorous and effective ligation of them. Moreover, the surgeon avoids taking big bites when suturing and making a ‘‘blind dearterialization’’ that would be at greater risk of bleeding and might partially alter both the anatomy and dynamics of the rectal wall, thus affecting rectal compliance and causing postoperative functional disturbances.

Effect of nifedipine on anorectal sensorimotor functions in health and fecal incontinence

The mechanisms of increased rectal stiffness in women with fecal incontinence (FI) and rectal urgency are not understood. Our hypothesis was that distention-induced activation of mechanosensitive L-type calcium channels in smooth muscle contributes to increased rectal stiffness in FI. Anal pressures, rectal distensibility (compliance, capacity, and contractile response to sinusoidal oscillation), and rectal sensation were assessed before and after oral nifedipine (30 + 10 mg) or placebo in 16 women with FI and 16 asymptomatic women. At baseline, FI patients had a lower anal pressure increment during squeeze (health, 66.9 ± 7.6: FI, 28.6 ± 5.9, mean ± SE, P ≤ 0.01), lower rectal capacity (P = 0.052), and higher rectal pressures during sinusoidal oscillation (health, 13.7 ± 3.2: FI, 21.7 ± 1.4, mean ± SE, P = 0.02) than the healthy women, which suggests an exaggerated rectal contractile response to distention. Nifedipine decreased mean BP, increased heart rate (P = 0.01 vs. placebo), and reduced anal resting pressure (P ≤ 0.01) but did not significantly modify rectal distensibility in health or FI. Plasma nifedipine concentrations (health, 103 ± 21 ng/ml: FI, 162 ± 34 ng/ml) were correlated with increased rectal compliance (r = 0.6, P = 0.02) in all study participants and, in healthy subjects, with decreased rectal pressures during sinusoidal oscillation (r = 0.86, P = 0.01), indicative of reduced stiffness. No consistent effects on rectal perception were observed. These observations confirm that FI is associated with anal weakness and increased rectal stiffness. At therapeutic plasma concentrations, nifedipine reduced anal resting pressure but did not improve rectal distensibility in FI, outcomes that argue against a predominant contribution of myogenic L-type calcium channels to reduced rectal distensibility in FI.

* The effects of antimuscarinic agents on rectal compliance in patients with supraconal spinal cord injury

IntroductionConstipation affects up to 80% of spinal cord injury (SCI) patients and is cause of significant reduction of quality of life. Rectal compliance is determined by the rectal wall properties...

The role of the spinal cord in bowel dysfunction secondary to multiple sclerosis: a comparison with supra-conal spinal cord injury

<h3>Introduction</h3> Bowel dysfunction in multiple sclerosis (MS) and spinal cord injury (SCI) is common, affecting up to 2/3 of patients, with constipation and incontinence often co-existing. In MS we have shown that spinal cord involvement by the disease predicts bowel dysfunction. Spinal disease burden is easily measured clinically by EDSS (expanded disability status scale, 0–4.5 = mild disability, 5–10 = high disability). In supraconal-SCI the autonomic dysfunction underlying bowel symptoms causes increased rectal compliance (RC). We hypothesised that spinal cord involvement by MS is responsible for the autonomic dysfunction affecting the rectum, hence compared RC between MS, supraconal-SCI patients and normal controls. <h3>Methods</h3> Forty-five MS patients with bowel symptoms were divided in two groups according to EDSS: MS-A (EDSS &lt; 5, n = 25) and MS-B (EDSS &gt; 5, n = 20). Rectal compliance and Wexner constipation and incontinence scores were compared with 19 Supraconal-SCI patients and 25 normal controls. Age, gender and parity were well-matched between groups. <h3>Results</h3> <i>Rectal compliance (ml/mmHg)</i> post-hoc analysis in table 1. <i>Wexner-Incontinence:</i> <b>MS-A</b> (6.12 ± 4.72) vs <b>MS-B</b> (9.8 ± 6.4) p = 0.96 <b>MS-A</b> (6.12 ± 4.72) vs <b>Spinal</b>(10.8 ± 5.3)p = 0.033 <b>MS-B</b> (9.8 ± 6.4) vs <b>Spinal</b>(10.8 ± 5.3) p = 0.883. <i>Wexner-Constipation:</i> <b>MS-A</b> (10.8 ± 5.3) vs <b>MS-B</b> (11.3 ± 4.3) p = 0.951 <b>MS-A</b> (10.8 ± 5.3) vs <b>Spinal</b> (15.4 ± 5.8) p = 0.025 <b>MS-B</b> (11.3 ± 4.3) vs <b>Spinal</b> (15.4 ± 5.8) p = 0.065. In the MS group there was a strong relationship between EDSS and RC (r = 0.438, p = 0.003; β = 0.487, p = 0.001). <h3>Conclusion</h3> Rectal compliance is increased similarly in both MS patients with high disability and supraconal-SCI patients, suggesting that similar autonomic dysfunction underlies bowel symptoms in both groups. Bowel dysfunction in MS is multifactorial, but spinal cord involvement by MS seems critical to development of both constipation and incontinence.