Effect of anterior resection on anal sphincter function

Minor difficulties with continence may occur after low anterior resection. Intraoperative injury to the internal anal sphincter or its nerve supply may contribute to this. To study the effect of low anterior resection on the anal sphincter mechanism, anal manometry was performed on 20 patients before and 10 days after resection. Fifteen patients were studied again 6 months after operation. Resting, maximum squeeze and squeeze increment pressures were recorded. Intraoperative manometry (n = 11) and presacral nerve stimulation (n = 6) were performed to determine whether peroperative injury to the internal anal sphincter had occurred. Resting and maximum squeeze anal canal pressures were reduced by low anterior resection, and did not recover. The squeeze pressure increment did not change. Division of the inferior mesenteric artery, full mobilization of the rectum and mesorectum, and rectal transection did not affect resting anal pressure, which was reduced after EEA anastomosis (mean (s.e.m.) before, 40(5) mmHg; after, 27(4) mmHg; P less than 0.05, n = 5). Presacral nerve stimulation produced relaxation of the internal sphincter. Anal sphincter pressures are reduced after low anterior resection. The external anal sphincter and the nerve supply to the internal anal sphincter appear intact. A direct injury to the internal sphincter is postulated.     

Anorectal function after partial intersphincteric resection in ultra‐low rectal cancer

Aim To investigate the feasibility and efficacy of intersphincteric resection (ISR), in terms of postoperative anorectal function, for ultra‐low rectal cancer in mainland China. Method A total of 43 patients who consecutively underwent curative partial ISR for ultra‐low rectal cancer between 2006 and 2009 were enrolled in the study. Defaecatory function was assessed, using detailed questionnaires, 3, 6 and 12 months after surgery. The Wexner score was used to assess faecal continence, and anal manometry studies were performed to analyse anal sphincter function. Results Overall defaecatory function was assessed as being satisfactory in 41 of 43 patients. Twelve months after surgery, the mean Wexner score was 4.0 ± 3.6. Anal manometry studies showed a significant change at 3 months and further, gradual, improvement over the following year. During the postoperative period, maximum squeeze pressure reached a normal value of 174.1 ± 19.5 mmHg (P = 0.041) by 6 months and resting pressure was 42.4 ± 5.6 mmHg by 12 months, which was close to the preoperative level (P = 0.038). Conclusion Because of the satisfactory recovery of defaecatory function and good oncological results, partial ISR may be recommended as an effective sphincter‐preserving operation for patients with ultra‐low rectal cancer.     

Anorectal manometry with water‐perfused catheter in healthy adults with no functional bowel disorders

Anorectal manometry provides an objective assessment of anal sphincter pressure and rectal sensitivity and anorectal reflexes in response to distension. However, its clinical utility is hampered by a lack of standardized protocols and normative data from healthy subjects. Previous studies have used water‐perfused systems in normal subjects, but some adopted a rapid pull‐through technique; others did not evaluate rectal sensations and others did not carefully exclude patients with functional bowel disorders. Objective To evaluate anorectal function in healthy adults without functional bowel disorders, using a water‐perfused system with the stationary technique in order to obtain normative values for anorectal manometry. Method Fifty‐two healthy volunteers with no Rome II diagnostic criteria for functional bowel disorders, including only nulliparous women, underwent anorectal manometry with a water‐perfused system, according to a standardized protocol. Results Maximum squeeze pressure of the anal sphincter as well as the area under the pressure‐time curve during squeeze was significantly lower in women than men (P < 0.01), while sphincter length, resting pressure, volume thresholds for reflex inhibitory recto‐anal and rectal sensations were similar. Conclusions This study describes a protocol for stationary anorectal manometry using a water‐perfused system, and a method for analysing the various parameters obtained during the procedure, as recently suggested in the international literature. It supplies normative data obtained in a population of healthy subjects including nulliparous women, with no functional bowel disorders.     

The relationship between internal rectal prolapse and internal anal sphincter function

Aim Faecal incontinence is commonly seen in patients with internal rectal prolapse (IRP), although the mechanism is not clear. This study assessed the relationship between IRP and anal sphincter function. Method Patients both with IRP diagnosed on proctography and those with external rectal prolapse (ERP) were identified from a prospective database generated from a tertiary referral pelvic floor clinic. The results of anorectal manometry were analysed, and the relationship between sphincter pressure and grade of prolapse was assessed. Results A total of 515 patients were identified with clinical evidence of ERP or proctographic evidence of internal and external prolapse. There were 88 with grade 5 or external prolapse [mean maximal resting pressure (MRP) 28.5 (standard error 2.1) mmHg], 156 with grade 4 prolapse [44.0 (1.8) mmHg], 153 with grade 3 prolapse [49.2 (1.6) mmHg], 88 with grade 2 prolapse [56.2 (2.1) mmHg] and 29 patients with grade 1 rectal prolapse [56.8 (4.5) mmHg]. There was a significant reduction in the mean MRP with increasing grade of prolapse from grade 2 to 5. By contrast, there was no relationship between prolapse grade and mean maximal squeeze pressure, except in patients with ERP, in whom the squeeze pressure was significantly lower compared with patients with IRP. Conclusion This is the first large‐scale study to show the relationship between internal prolapse and MRP. The observation that squeeze pressure is unchanged suggests that the effect of internal prolapse on continence occurs mainly through a reduction in internal anal sphincter tone.     

Neoadjuvant radiochemotherapy for patients with locally advanced rectal cancer leads to impairment of the anal sphincter

Neoadjuvant radiochemotherapy (RCTx) has become an acceptable therapy for patients with locally advanced rectal cancer. However, little is known about the effect of the RCTx on the function of the anal sphincter. Forty-one consecutive patients with locally advanced rectal cancer (cT3, N+) underwent neoadjuvant RCTx with subsequent resection. All patients were examined clinically and by anal manometry for their anal sphincter function. A multichannel water-perfused catheter system was used, and resting pressure, maximum squeeze pressure, and length of the anal high-pressure zone were determined prior to the neoadjuvant therapy and before the operation. The length of the high-pressure zone did not change after the neoadjuvant therapy. However, resting and maximum squeeze pressure decreased significantly after preoperative RCTx. This effect was more pronounced for the resting pressure rather than the maximum squeeze pressure, indicating that the internal sphincter is primarily affected. These results correlated with the clinical data showing an impaired continence status in patients treated with neoadjuvant therapy. Neoadjuvant RCTx leads to impairment of the anal sphincter predominantly in the internal sphincter. This effect may enhance the surgical impairment of continence after curative resection.     

External and internal anal sphincter responses to rectal distension in normal subjects and in patients with idiopathic faecal incontinence

The responses of the external anal sphincter and the internal anal sphincter to rectal distension were studied in 18 female patients who had idiopathic faecal incontinence with perineal descent and 11 female control subjects, by measuring pressures at six sites within the anal canal and the electrical activity of the external sphincter. The pressure profile in the normal anal canal, at rest, was asymmetric with the highest pressure recorded in the outermost channels. Rectal distension caused a transient increase in the activity of the external sphincter, which was associated with an increase in anal pressure, particularly in the outermost two channels. This was followed by a symmetrical reduction in anal pressure throughout the anal canal, caused by relaxation of the internal sphincter and shortening of the high-pressure zone. Two patterns of response were observed in the patients with idiopathic incontinence. Twelve patients (group 1) showed normal anal relaxation, but the maximum anal pressures recorded during rectal distension or a conscious squeeze were abnormally low, suggesting weakness of the external anal sphincter. The remaining six subjects (group 2), who were older than the group 1 patients, had much lower resting pressures and showed only external sphincter contraction in response to rectal distension, with no obvious internal sphincter relaxation. However, the maximum pressures recorded during a conscious contraction of the external sphincter were lower in this group than in the normal control subjects. These results suggest that group 2 patients have impaired internal anal sphincter tone, as well as external anal sphincter weakness. This may explain why all except one of the group 2 patients, compared with only 17 per cent of group 1 patients, reported incontinence to both solids and liquids.     

Anorectal function and defecation dynamics in patients with rectal prolapse

Seven female patients with clinical rectal prolapse and nine healthy female control subjects were studied with anorectal manometry, external sphincter electromyography, and a saline continence test. Resting anal tone, maximum voluntary squeeze, and rectal functional capacity were significantly decreased in the rectal prolapse patients (p less than 0.02). During defecation attempts, external sphincter or pelvic floor electromyographic activity decreased in all of the control subjects, whereas six prolapse patients showed increased electromyographic activity and one had no change in activity (p less than 0.01). Continence to saline solution was also significantly impaired in prolapse patients (p less than 0.001). Postoperative studies in three patients who underwent repair revealed persistence of abnormal anorectal function and defecation dynamics. Patients with rectal prolapse have impaired resting and voluntary sphincter activity, decreased functional rectal capacity, and impaired continence. The failure of normal relaxation of the external sphincter or pelvic floor during defecation attempts, as demonstrated in the patients described herein, may contribute to the development of prolapse and denervation sphincter injury seen in such patients.     

Childbirth and incontinence: a prospective study on anal sphincter morphology and function before and early after vaginal delivery

PURPOSE: Disturbance of anal continence is a well-known problem after vaginal delivery. However, only few and incongruent data on the incidence and pathogenesis of postpartum incontinence are available. This study examined the effects of vaginal delivery on anal continence prospectively.METHODS: In 42 unselected women anal vector manometry and endoanal ultrasonography were performed, and pudendal nerve terminal motor latency (PNTML) and rectal sensibility were measured in the 32th week of pregnancy and 6 weeks after delivery. Continence was evaluated according to the Kelly-Holschneider score. Patients with occult sphincter defects were additionally followed-up 12 weeks after vaginal delivery. To exclude any effect of pregnancy alone ten patients with elective cesarian section served as controls.RESULTS: Overall continence after vaginal delivery did not differ significantly from that before delivery, there was a significant reduction in postpartum anal squeeze and resting pressures in all patients. Obstetric tears of grade III or IV occurred in 9% of the patients. Endosonography revealed occult lesions of the internal and external anal sphincter in an additional 19% of women who clinically seemed to have an intact sphincter. Manometric results and continence in these women did not differ significantly from those with intact sphincter and remained unchanged after 12 weeks. PNTML and rectal sensibility were not affected by vaginal delivery. After cesarian section there were no changes in continence, anal pressures, rectal sensibility, or PNTML.CONCLUSIONS: Vaginal delivery leads to direct mechanical trauma to the anal sphincters, while stretch and distension of the pudendal nerve seem to be of minor importance. Only endoanal ultrasonography is suitable for detection of occult sphincter lesions.     

Physiologic Basis Of Digital–Rectal Stimulation For Bowel Evacuation In Patients With Spinal Cord Injury: Identification Of An Anorectal Excitatory Reflex

Abstract

Background and purpose: Although advances in rehabilitation practices, pharmacology, and surgery offer new bowel program alternatives, digital-rectal stimulation is still utilized to facilitate defecation in patients with spinal cord injury (SCI) . We speculated that defecation induced by such a technique is mediated through a reflex mechanism.

Methods: The study comprised 18 healthy volunteers (10 men, 8 women, mean age 36.6 ± 9.7 years) and 9 patients with SCI (6 men, 3 women, mean age 35 .1 ± 11 .2 years). The anal canal was dilated by a balloon inflated in 2-ml increments to 10 ml, and rectal pressure response was then recorded. The test was repeated after separate block of the external and internal anal sphincters and after individual anesthetization of the anal canal and rectum.

Results: In normal subjects, the rectal pressure rose significantly (p<0.01) with 2-ml inflation. Increases in anal dilatation effected further rectal pressure elevations (p < 0.001 ), although there were no significant differences among the 4-, 6-, and 10-ml distensions (p > 0.05). The rectal pressure rise occurred with external, but not with internal, sphincter paralysis. In the subjects with paraplegia, there was no rectal pressure response to the 2- and 4-ml anal dilatations, while the 6-, 8-, and 10-ml distensions effected significant pressure increases (p<0.001, p<0.001, p<0.001, respectively) that did not differ significantly among the 3 distending volumes. Internal sphincter inhibition,in contrast to the external sphincter, produced no rectal pressure response. In both normal subjects and subjects with paraplegia, the rectal pressure response did not occur after individual anesthetization of the rectum and anal canal.

Conclusions: Anal dilatation induces rectal contraction through stimulation of mechanoreceptors, possibly in the internal sphincter.Rectal contraction upon anal dilatation suggests a reflex relationship that was absent onindividual anesthetization of the possible2arms of the reflex arc: anal canal and rectum.This relationship, which we term the "anorectal excitatory reflex ," appears to be evoked on digital anal dilatation. The reflexmight be of diagnostic significance in defecationdisorders and has the potential to be used as an investigative tool.     

Changes in fatigability of the striated anal canal after childbirth

Aim Anal manometry is an established assessment tool for patients with faecal incontinence. Fatigue rate index (FRI) has been shown to discriminate between symptomatic patients and controls. The aim of this study was to compare manometry and fatigability of the anal canal in nulliparous women before and after childbirth. Method An air‐filled manometry device was used to record maximum resting and squeeze pressures, fatigue rate (recorded over 20 s) and FRI. Recordings were made before and after vaginal delivery. Results Nineteen women were studied. Resting anal canal pressure was not significantly different before and after delivery (57.1 ± 13.6 vs 51.1 ± 11.9 cmH₂O, P = 0.1). Squeeze pressure was significantly lower postpartum (106.5 ± 43.6 vs 75.5 ± 45.6 cmH₂O, P < 0.001). Fatigue rate was significantly reduced postpartum (?129.5 ± 74.7 vs?76.1 ± 54.8 cmH₂O/min, P = 0.001), but FRI was not significantly altered (1.23 ± 1.49 vs 1.41 ± 1.27 min, P = 0.09). Conclusion Maximal squeeze pressure and fatigue rate of the anal canal are significantly reduced after childbirth. Resting anal canal pressure and FRI are not significantly different.     

A common pathophysiology for full thickness rectal prolapse, anterior mucosal prolapse and solitary rectal ulcer

Anorectal pressures at rest, during conscious contraction of the external sphincter, during serial distension of the rectum and during straining to inflate a balloon were measured in 56 patients (21 patients with full thickness rectal prolapse, 24 patients with anterior mucosal prolapse, 11 patients with solitary rectal ulcer) and in 30 normal subjects. Both basal and squeeze pressures were significantly lower in the three groups of patients compared with matched normal controls (P less than 0.05). During increases in intra-abdominal pressure, anal pressure remained above maximum rectal pressure (P less than 0.05) in normal controls, with the highest anal pressures being recorded in the most caudal anal channels. In contrast, anal pressures tended to be lower than rectal pressures during this manoeuvre in patients with rectal prolapse, anterior mucosal prolapse and solitary rectal ulcer, and the highest pressures were recorded in the channels nearest the rectum. During serial distension of the rectum, 64 per cent of patients with solitary rectal ulcer, 75 per cent with anterior mucosal prolapse and 76 per cent with rectal prolapse, but only 10 per cent of controls, showed repetitive rectal contractions. The highest anal pressure always remained higher than rectal pressure during rectal distension in normal subjects (P less than 0.05) but not in patients. The threshold rectal volume required to cause a desire to defaecate and the maximum tolerable volume were significantly lower (P less than 0.05) in each of the patient groups, compared with normal subjects. The similarity in the results from patients with rectal prolapse, anterior mucosal prolapse and solitary rectal ulcer support the hypothesis that they share a common pathophysiology. In each of the groups, the rectum is hypersensitive and hyper-reactive, and weakness of the anal sphincter creates the conditions for prolapse of the rectum to occur into or through the anal canal.     

Correlation between anal manometry and endosonography in females with faecal incontinence

Objective Female faecal incontinence (FI) is largely because of sphincter injury at childbirth. Sphincter assessment aims to identify surgically correctable defects. We aimed to identify endoanal ultrasonography (EAUS) parameters that correlate with sphincter function. Method One hundred females with FI and 28 healthy asymptomatic females were prospectively assessed. Wexner FI score was recorded and all subjects underwent anorectal manometry and EAUS. Multiple EAUS parameters were assessed and correlated with external (EAS) and internal (IAS) anal sphincter function, determined by maximum squeeze pressure (MSP) and maximum resting pressure (MRP) respectively. Parameters included sphincter quality (echogenicity), thickness, perineal body thickness (PBT) and defect characteristics (angle, length). Results are expressed as medians and interquartile range (IQR). Results Median Wexner score was 14 (12–17). Maximum EAS thickness significantly correlated with MSP (P = 0.019). EAS defects were detected in 84 patients and seven controls (P < 0.0001). Full‐length EAS defects were only detected in FI group and had significantly lower MSP [MSP mmHg: full length 85 (65–103) vs partial length 119 (75–155), P = 0.006]. FI patients were more likely to have a mixed echogenicity of EAS compared with controls. EAS ring quality, PBT and defect angle were not significant. IAS quality was significantly associated with MRP [MRP mmHg: uniform 62 (43–82) vs mixed 47 (30.5–57.5), P = 0.002]. Conclusion Certain EAUS parameters can be predictive of anal sphincter function. These include the presence of an EAS defect and its length, EAS maximum thickness, IAS ring quality. Integration of these parameters can give better EAUS correlation with manometry for FI evaluation.     

Predicting anal sphincter defects: the value of clinical examination and manometry

Introduction and hypothesis

The aims of this study were, firstly, to determine the diagnostic accuracy of an anal incontinence score, clinical examination and anal manometry in identifying anal sphincter defects and, secondly, to establish manometric cut-off values associated with sphincter defects.

Methods

One hundred fifty-nine women were evaluated by clinical examination, anal manometry and endoanal ultrasound (EAU). Accuracy measures were calculated, using EAU as the gold standard.

Results

Perineal body length (p?=?0.84) and pelvic floor muscle strength (p?=?0.10) were not associated with anal sphincter defects. Anal inspection was associated with anal sphincter defects (p?Conclusions Clinical assessment has a poor sensitivity for detecting anal sphincter defects. The proposed manometric cut-off values can be used to either reassure or identify women who may need further assessment by EAU.     

Anal sphincter tears in patients with rectal prolapse and faecal incontinence

Objective Faecal incontinence often persists after surgery for rectal prolapse. Multiple mechanisms have been proposed as responsible, however, anal sphincter integrity has only been studied in a handful of cases. This study assesses the incidence of ultrasound detected anal sphincter tears in patients with rectal prolapse and faecal incontinence. Methods Retrospective search of medical records at Flinders Medical Centre over a 7‐year period to identify patients with full thickness rectal prolapse and faecal incontinence who had undergone endosonographical imaging of the anal sphincter complex. Anal manometry and pudendal nerve terminal motor latency studies were also included. Results Twenty‐one patients were identified (1 male, 20 female) of median age 67.5 years. Fifteen (71%) subjects had an abnormality in the anal sphincter complex on endoanal ultrasound. Of these, the defects in 4 (19%) patients were isolated to the internal sphincter, 3 (14%) to the external sphincter and in the remaining 8 (38%) subjects, defects were found in both internal and external sphincters. The degree of sphincteric defect was variable but at least 6 (29%) of the study group had full‐length external sphincter tears. In the 19 patients studied, anal manometry revealed reduced basal and squeeze pressures in the majority. Delayed pudendal nerve terminal motor latency was evident in 9 of 18 patients studied. Conclusion Anal sphincter tears are common in patients presenting with rectal prolapse and faecal incontinence. The faecal incontinence associated with prolapse appears to be multifactorial in aetiology. Anal sphincter defects are likely to contribute to persistent faecal incontinence or recurrence following rectal prolapse. Endoanal ultrasound derived knowledge of anal sphincter injury may guide surgical management in problematic cases.     

Normal ranges for anorectal manometry and sensation in women of reproductive age

OBJECTIVE: To derive a range of normal values for anal sphincter resting and squeeze pressure, and anorectal sensation in healthy women without anorectal disease before and after their first childbirth. METHOD: Nulliparous women undergoing anal physiology testing in the third trimester of pregnancy and 12 weeks after delivery. All were asked to undergo anal manometry and anorectal electrosensation testing. Maximum resting pressure, maximum squeeze pressure and anal thresholds to electrical current were assessed at 1 cm intervals down the anal canal. Rectal electrosensitivity thresholds were assessed 10 cm from the anal verge. RESULTS: A total of 286 women attended for antenatal investigations and 161 (56%) returned postpartum. The anal canal length was 3.9 +/- 0.6 cm antenatally and 3.9 +/- 0.6 cm postnatally. During pregnancy the 95% normal range for anal resting and squeeze pressures, anal and rectal sensation were 29-90 mmHg, 50-163 mmHg, 2-31 mA and 3-33 mA respectively. Post delivery the 95% normal ranges were 27-98 mmHg, 43-156, 2-12 mA and 0.1-34 mA respectively. Both antenatally and postnatally the manometry and sensitivity values were similar in women with and without bowel symptoms. CONCLUSION: This study is the largest series of normative data for anal manometry, and anorectal sensation in women before and after their first delivery. The antenatal values can serve to represent ranges for nulliparous women and the postnatal values ranges in primiparous women.     

Investigation of anal sphincter function following Mainz pouch type II urinary diversion after radical cystectomy

Purposes

Our aim was to evaluate the anal sphincter function following cystectomy with urinary diversion of Mainz pouch II.

Methods

Seventy-six patients were involved in our survey, and the cohort was for two groups divided. The first group was a retrospective review of 40 patients with examination of the state of continence. Comparative examinations on anal sphincter function and the quality of life survey were carried out. The second group consisting of 15 patients underwent a prospective investigation including rectal manometry in both the pre- and postoperative periods. Measurements of resting anal sphincter pressure (RASP), maximal anal closing pressure (MACP) and the function of the recto anal inhibitions reflex were taken.

Results

In the first part of our investigation, 80% of the patients were considered as continent. There were no significant differences observed between RASP values in the cases of continent as well as of incontinent patients (79.2?±?2 vs. 73.6?±?68.4?mmHg, p?=?0?C53); however, the MACP values of the continent patients were significantly higher (204.3?±?22.8 vs. 117.3?±?14?mmHg, p?=?0.001). In the course of the second experiment, both the RASP (86.3?±?18.7 vs. 76.1?±?13.9?mmHg p?=?0.0049) and the MACP (232.2?±?53.8 vs. 194.1?±?74.5?mmHg, p?=?0.0054) were detected as decreasing in the case of the incontinent group.

Conclusions

A decrease in rectal sphincter function is responsible for incontinence following Mainz pouch type II diversion, and this dysfunction can be correlated with the surgery. Ureterosigmoideostomy is therefore considered as a useful method of urinary diversion only in selected cases with proven good sphincter function.     

Laparoscopic rectopexy for complete rectal prolapse

Background: The purpose of this study was to evaluate the clinical outcome of laparoscopic rectopexy and its effect on anorectal function investigations. Methods: Twelve patients with complete rectal prolapse without constipation underwent laparoscopic rectopexy. Pre- and postoperative evaluation included scoring of incontinence, anorectal manometry, and anal endosonography. Results: No recurrences of rectal prolapse were seen (median follow-up 19 months). Continence improved in eight of nine preoperatively incontinent patients. Two patients had mild constipation after surgery. Median maximum basal pressure measured by anorectal manometry increased from 20 to 25 mmHg (p=0.005) and the rectoanal inhibitory reflex improved in seven patients (p=0.03). Rectal sensitivity did not change significantly. Endosonography showed asymmetry and thickening of the internal anal sphincter and submucosa preoperatively. After surgery the maximum internal anal sphincter thickness decreased from 3.0 mm to 2.6 mm (p=0.02). Conclusions: Laparoscopic rectopexy improved continence in our patients. Anorectal function tests show a partial recovery of the internal anal sphincter. Laparoscopic rectopexy combines the low morbidity of minimal invasive surgery with the good outcome of abdominal rectopexy.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, Florida, USA, 11–14 March 1995     

Fatigue rate of the external anal sphincter

Aim Studies of skeletal muscle show that fatigue rate corresponds to the proportion of fast‐twitch and slow‐twitch fibres that are present in the muscle. Limited work has been done on the fatigue rate of the external anal sphincter. We have prospectively studied fatigability of the external anal sphincter in women with faecal incontinence and women with normal bowel control. Method Anorectal manometry was measured by a station‐pull technique using a water‐filled microballoon. Fatigue rate was calculated from anal pressure measurements taken every 0.1 s over a 20‐s squeeze. Results Women with faecal incontinence (n = 88, median ?12 cmH₂O/min) were less susceptible to fatigue than women with normal bowel control (n = 36, median ?43 cmH₂O/min) (P < 0.01). The external anal sphincter was less susceptible to fatigue with increasing age (P < 0.01, r = 0.499). In women with normal bowel control and in women with faecal incontinence fatigue rate was negatively correlated with maximum squeeze pressure (P < 0.01, r = ?0.287; P < 0.01, r = ?0.579). Conclusion The external anal sphincter was less susceptible to fatigue with increasing age. Women with faecal incontinence have a weaker but more fatigue‐resistant external anal sphincter. This might correspond to a higher proportion of slow‐twitch muscle fibres. Histological studies are needed to examine this hypothesis.     

低位直肠癌括约肌间切除超低位吻合的疗效评估

目的评价超低位直肠癌行括约肌间切除手术（ISR）后的舡肠动力学变化、肛门功能及肿瘤根治效果。方法总结分析2004年1月至2007年8月间施行ISR手术的30例超低位直肠癌患者的临床资料。结果30例患者肿瘤距肛缘2．5～4．0（平均3．4）cm。与术前比较．术后肛管静息压、肛门最大收缩压和直肠最大耐受容积明显降低（P〈0．01）．有27例（90．0％）患者术后肛门直肠抑制反射消失,且随着时间推移无明显恢复。按Williams的排便自制标准．术后3、6、12个月分别有86．7％、93．3％和96．7％的患者达到功能良好效果。全组患者随访1年至3年8个月．无死亡病例;未出现盆腔或吻合口局部复发、远处转移和吻合口瘘。10例术后出现肛周粪渍性湿疹,2例结肠黏膜脱出,1例肛管狭窄。结论ISR超低位吻合保肛手术治疗低位直肠癌可以达到良好的根治性．并能较好地保留肛门功能。     

Functional results after laparoscopic rectopexy for rectal prolapse

We investigated the functional results after laparoscopic rectopexy for rectal prolapse in 29 patients at least 12 months postoperatively. Twenty patients were evaluated completely pre- and postoperatively (median 22 months postoperatively, range 12 to 54 months). Six patients were interviewed by telephone, two patients were lost to follow-up, and one patient died of causes unrelated to rectal prolapse. Patients underwent a proctologic examination, anoscopy, rigid sigmoidoscopy, fluoroscopic defecography, and anorectal manometry pre- and postoperatively, and an additional standardized interview postoperatively. Anorectal manometry showed a significant increase in maximum anal resting and squeeze pressures postoperatively (resting pressure 72 ±8 vs. 95 ±13 mm Hg, pre- vs. postoperatively; P = 0.046; squeeze pressure 105 ±17 vs. 142 ±19 mm Hg, pre- vs. postoperatively; P = 0.035), and continence improved postoperatively (Wexner incontinence score 6.0 ±1.0 vs. 3.9 ± 0.8 pre- vs. postoperatively, P = 0.02). Twenty (77%) of 26 patients were satisfied with the operative result, but functional morbidity was observed in four patients, with two patients complaining of severe evacuation problems. Rectal prolapse recurred in one patient 42 months postoperatively (recurrence rate 1 [3.8%] of 26 patients). Functional results were very similar to those obtained after open rectopexy, with symptoms of prolapse and incontinence improved in the great majority of patients. Presented at the Fortieth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Fla., May 16–19, 1999.