Lateral internal sphincterotomy together with haemorrhoidectomy for treatment of haemorrhoids: a randomised prospective study.

OBJECTIVE: To investigate anorectal manometric findings in patients with haemorrhoids and to evaluate the clinical effects and physiological consequences of adding a lateral internal sphincterotomy (LIS) to haemorrhoidectomy. DESIGN: Randomised prospective study. SETTING: Teaching hospital, Naples. PATIENTS: 48 consecutive patients with prolapsed piles who had anorectal manometry; 10 healthy volunteers served as controls. INTERVENTIONS: Resting and squeeze pressures, sphincter length and rectoanal inhibitory reflex were recorded. 6 patients were excluded because anal pressures were not raised, so 42 patients were randomised. 22 patients had haemorrhoidectomy plus LIS; and 20 had haemorrhoidectomy alone. MAIN OUTCOME MEASURES: Morbidity, continence, and anorectal manometry. RESULTS: Sphincter anomalies were found in 87.5% (n = 42) of patients. Haemorrhoidectomy alone did not affect anal pressures, which returned to the normal ranges after sphincterotomy. Those who had LIS did better postoperatively than those who had did not. 4 patients who did not have a sphincterotomy developed anal strictures. No patient who had LIS developed incontinence of faeces. CONCLUSIONS: High anal pressures are common in patients with haemorrhoids suggesting that they may have a pathogenetic role; anorectal manometry is useful in the investigation of anal pressure patterns; and when indicated, lateral sphincterotomy avoids pain, urinary retention, and stenosis, and is safe.     

A manometric study of anorectal function after surgery for anal fistula, with special reference to incontinence

Anorectal function was manometrically studied in 199 adults on average 9 years after laying open of anal fistula, in order to determine the factors adversely affecting anal continence. Resting anal pressure, and especially squeeze and voluntary contraction pressures, were significantly reduced in the 67 patients with defective anal control. Maximal squeeze and contractile pressures were significantly lower in women than in men but, like maximal resting pressure, were uninfluenced by age. Fistula type significantly influenced maximal resting and squeeze pressures, with tendency to low pressures and high incidence of defective anal control after operation for high intermuscular fistula. Maximal contractile power was unrelated to extent of external sphincter division. Rectal sensation and activity of the rectoanal reflexes did not appreciably differ between the continent patients and the others. Digital assessment of sphincter tone at rest and at maximal contraction correlated well with the respective anal pressures, but was an unreliable indicator of anal continence. The manometric findings warrant maximal preservation of the anal sphincter musculature, but fistula healing must not be thereby endangered.     

A contraction response of the internal anal sphincter to Botulinum toxin: does low‐pressure chronic anal fissure have a different pathophysiology?

Aim A subset of low‐pressure fissures is not associated with typical internal anal sphincter hypertonia and may involve a different pathophysiological mechanism. We aimed to assess the manometric response of the internal anal sphincter to botulinum toxin in low‐pressure fissures compared to high‐pressure fissures. Method Twenty five units of botulinum toxin (Botox^TM) were injected directly into the internal anal sphincter. Maximum resting pressure (MRP) and maximum squeeze increment (MSI) were documented at baseline and four weeks after injection. Results Nine (31%) of 29 patients had a low‐pressure fissure. Those with an anterior fissure had a significantly lower median baseline MRP than those with a posterior fissure (66 vs 83 mmHg, P = 0.009). Significantly more patients with low‐pressure fissures developed a contraction or no response (78%vs 30%, difference 48%, 95% CI 14–82%, P = 0.006). Those developing a contraction response had a lower mean baseline MRP than those developing a relaxation response (56 vs 86 mmHg, difference 30 mmHg, 95% CI 17–43%, P < 0.001). Conclusion Botulinum toxin appears to have an atypical contraction effect on the internal anal sphincter in low‐pressure (usually anterior) fissures. This may be accounted for by blockade of acetylcholine released at parasympathetic nerve terminals and the sympathetic ganglion (relaxation). Low pressure fissures may be physiologically different from high‐pressure fissures.     

Effect of biofeedback and electrostimulation on sphincter function in fecal incontinence

The following study reports on the effect of biofeedback and transanal electric stimulation as a conservative method in the therapy of idiopathic fecal incontinence. 22 consecutive patients in whom the diagnosis "idiopathic incontinence" was established after endoscopy, endoanal ultrasound and measurement of pudendal nerve terminal motor latency underwent combined sphincter training for 3 months. The results were evaluated prospectively by clinical classification using a modified Kelly-Holschneider-score and anal manometry before and after treatment. Combined biofeedback led to a significant increase of the continence score in 18 of 22 patients (7.7 +/- 3.8 vs. 9.3 +/- 3.0, p = 0.004). Both squeeze (77 +/- 28 mmHg vs. 92 +/- 32 mmHg, p = 0.047) and resting pressures (40 +/- 19 vs. 52 +/- 23 mmHg, p = 0.015) increased significantly during the training period. There were no significant differences in squeeze and resting asymmetry indexes, sensory and urge thresholds and maximal tolerable volumes. The prolongation of biofeedback training from 3 to 6 months in 9 patients did not change clinical or manometric results significantly. CONCLUSIONS: The combination of biofeedback training with anal electrostimulation increases anal squeeze and resting pressures, thus leading to an improvement of clinical incontinence symptoms. Therefore it should be the first choice in the therapy of idiopathic fecal incontinence. A training period of 3 months seems to be sufficient.     

A prospective manometric study of the effect of anal fistula surgery on anorectal function

In 31 adults consecutively undergoing surgery for anal fistula (opening of fistulous tract), anorectal manometry was performed before and 7 months after the operation. The resting pressure was significantly reduced in the distal 3 cm of the anal canal postoperatively. Voluntary sphincter contraction was less markedly affected. Maximal squeeze pressure and maximal contractile power were significantly reduced, however, especially in women and after division of the external sphincter muscle. The pressures were significantly lower in women than in men, particularly after operation, and defective anal control was associated with reduced squeeze pressure. It is therefore suggested that in selected cases, primarily women, anal pressure should be measured preoperatively and division of the external sphincter muscle avoided if the pressure is low. Constant rectoanal inhibitory reflex was elicited by a significantly smaller distending volume and lower rectal pressure postoperatively than preoperatively which, like the reduced resting pressure, indicated impaired function of the internal sphincter muscle.     

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.     

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.     

Effect of rectal distension on voluntary external anal sphincter function in healthy subjects

Aim Quantification of the anorectal reflex function is critical for explaining the physiological control of continence. Reflex external anal sphincter activity increases with rectal distension in a dynamic response. We hypothesized that rectal distension would similarly augment voluntary external anal sphincter function, quantified by measuring the anal maximum squeeze pressure. Method Fifty‐seven subjects (32 men, 25 women; median age 62 years), with normal anal canal manometry and endoanal ultrasound results, underwent a rectal barostat study with simultaneous anal manometry. Stepwise isovolumetric 50‐ml distensions (n = 35) or isobaric 4‐mmHg distensions (n = 22) above the minimum distending pressure were performed (up to 200 ml or 16 mmHg respectively), whilst anal resting pressure and maximum squeeze pressure were recorded and compared with the baseline pressure. Results The distension‐induced squeeze increment was calculated as the maximum percentage increase in maximum squeeze pressure with progressive rectal distension. This was observed in 53 of the 57 subjects as a mean ± standard deviation (range) increase of 32.8 ± 24.1 (?5.5 to 97.7)%. The mean ± standard deviation (range) distension‐induced squeeze increment in male subjects was 36.1 ± 25.7 (?5.5 to 97.7)% and in female subjects was 28.1 ± 20.1 (?3.8 to 70.2)%. There was no significant difference between the sexes (P = 0.194). Conclusion Rectal distension augments external anal sphincter function, confirming the existence of a dynamic rectoanal response. This may represent a quantifiable and important part of the continence mechanism.     

Comparison of digital and manometric assessment of anal sphincter function

Anal sphincter function was assessed by digital examination and anal canal manometry in 66 patients and controls. Digital scores were allotted by using visual analogue scales for basal and squeeze sphincter function and were compared with the corresponding pressures. There were good correlations between digital basal score and maximum basal pressure (Spearman rank correlation coefficient rs = 0.56, P less than 0.001), and digital squeeze score and maximum squeeze pressure (rs = 0.72, P less than 0.001). There were wide ranges of sphincter function on digital and manometric assessment with considerable overlap between patient groups. Digital scores detected differences in sphincter function between patient groups as accurately as manometry. The sensitivities and specificities of digital scores and anal canal manometry in segregating continent and incontinent patients were similar. It was concluded that digital estimation was equally as good as assessment of anal sphincter function as anal canal manometry.     

Sphincter injury after anal dilatation demonstrated by anal endosonography.

Anal dilatation is still used in the treatment of anal fissure and haemorrhoids. Using anorectal physiology and anal endosonography we have studied 12 men presenting with faecal incontinence following anal dilatation. Resting anal pressures were low, pudendal nerve latencies were normal; 11 men had a disrupted internal anal sphincter and in ten this was extensively fragmented. Three also had defects of the external anal sphincter. These findings demonstrate for the first time the nature of the structural injury which may be caused by anal dilatation.     

The usefulness of lateral internal sphincterotomy combined with hemorrhoidectomy in the treatment of hemorrhoids: a randomized prospective study

The aim of this prospective randomized study was to investigate anorectal manometric findings in hemorrhoid patients and to evaluate the clinical benefits and physiological consequences of additioning a lateral internal sphincterotomy (LIS) to haemorrhoidectomy. Anorectal manometry was preoperatively performed in forty-eight consecutive patients with prolapsed piles; resting and squeeze pressures, sphincter length and rectoanal inhibitory reflex were recorded. Ten healthy volunteers served as controls. Six patients were excluded because no raised and pressures were found. Forty-two patients were randomised: Group 1 (n = 22) patients underwent haemorrhoidectomy plus LIS; Group 2 (n = 20) patients underwent haemorrhoidectomy alone. Postoperative course was carefully evaluated; all patients were questioned about continence and anorectal manometry was repeated twice. Sphincter anomalies were found in 87.5% of patients. Haemorrhoidectomy alone did not affect anal pressures, which returned into the normal ranges after sphincterotomy. Postoperative course was better in LIS group. Anal stricture was seen in four patients without sphincterotomy; no patients with LIS experienced and incontinence. This study shows that high and pressures are very frequent in hemorrhoid patients; they are not due to hypertensive and cushions and might have a pathogenetic role. Anorectal manometry is very useful to identify patients with raised anal pressures; in these cases additioning a lateral internal sphincterotomy to haemorrhoidectomy seems justified; it significantly improves postoperative course and can be safely performed.     

Endocoil magnetic resonance imaging quantification of external anal sphincter atrophy.

BACKGROUND: Anal function depends on the integrity and quality of the sphincter muscles. The diagnosis of external anal sphincter atrophy on endocoil magnetic resonography has been associated with poor outcome from sphincter repair, although the imaging criteria for atrophy remain unclear. METHODS: Women with intact sphincters on endosonography and either normal (more than 60 cm H(2)O) (n = 9) or low (n = 16) squeeze pressures had endocoil magnetic resonography and electromyography. The area and fat content of the external anal sphincter and puborectalis were measured on mid-coronal magnetic resonography and images were graded as showing normal, intermediate or advanced atrophy. The definition of the external anal sphincter on endosonography and the thickness of the internal anal sphincter were also assessed. RESULTS: Women with a normal anal squeeze pressure had a larger external anal sphincter cross-sectional area (mean(s.d.) 240(56) versus 193(62) mm(2); P = 0.01) with a lower mean fat content (mean(s.d.) 23(4) versus 30(6) per cent; P < 0.001) than those with low squeeze pressures. There was an overall correlation between squeeze pressure, cross-sectional area (r = 0.32, P = 0.02) and fat content (r = - 0.51, P < 0.001). Patients with a thin (less than 2 mm) internal anal sphincter and/or a poorly defined external sphincter on endosonography were more likely to have atrophy (positive predictive value 74 per cent). CONCLUSION:: Potential endosonographic markers for external anal sphincter atrophy are suggested, and a visual scale for endocoil magnetic resonographic assessment has been validated.     

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.     

Anal manometric parameters: Predictors of outcome following anal sphincter repair?

Controversy exists over the utility of manometry in the management of fecal incontinence. In light of newer methods for the management of fecal incontinence demonstrating favorable results, this study was designed to evaluate manometric parameters relative to functional outcome following overlapping sphincteroplasty. Twenty women, 29 to 84 years of age (mean age 50 years), with severe fecal incontinence and large (≥50%) sphincter defects on ultrasound were studied. All participants underwent anal manometry (mean resting pressure, mean squeeze pressure, anal canal length, compliance), pudendal nerve terminal motor latency (PNTML) testing, and completed the American Society of Colon and Rectal Surgeons fecal incontinence severity index (FISI) survey before and 6 weeks after sphincter repair. Statistical analysis for all data included the Wilcoxon rank-sum test, Mann-Whitney test, and Spearman’s correlation. Significant perioperative improvement was seen in the absolute resting and squeeze pressures and anal canal length. Overlapping sphincteroplasty was also associated with significant improvement in fecal incontinence scores (FISI 36 vs. 16.4; P = 0.0001). Although no single preoperative manometric parameter was able to predict outcome following sphincteroplasty, preoperative mean resting and squeeze pressures as well as anal canal length inversely correlated with the relative changes in these parameters achieved postoperatively. These findings suggest that either the physiologic parameters studied are not predictive of functional outcome or the scoring system used is ineffective in determining function. The perioperative paradoxical changes in resting pressure, squeeze pressure, and anal canal length would support the use of overlapping sphincteroplasty in patients with significant sphincter defects and poor anal tone.     

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.     

Anterior anal fissures are associated with occult sphincter injury and abnormal sphincter function

Objective The pathogenesis of chronic anal fissure (CAF) remains incompletely understood but most are associated with a high resting anal pressure and reduced perfusion at the fissure site. To date, no major distinction has been made between anterior and posterior anal fissures and their aetiology and treatment. We compared anterior and posterior fissures in patients who have failed to respond to medical treatment with respect to their underlying aetiology, anal canal pressures and sphincter muscle integrity. Method Seventy consecutive patients (54 female:16 male) with a symptomatic CAF and 39 normal controls (19 female:20 male) without evidence of significant ano‐rectal pathology were prospectively assessed by manometry and anal endosonography. Results Anterior anal fissures were identified in a younger age group [33 years (IQR 26–37) vs 41 years (IQR 36–52)] and predominantly in women. Anterior fissure patients were significantly more likely to have underlying external anal sphincter defects compared with posterior fissures [OR 10.9 (95% CI 3.4–35.4)]. Maximum resting pressure was not significantly elevated for anterior fissures compared with controls (P = 0.316) but was significantly elevated in posterior fissures (P = 0.005). The maximum squeeze pressure was significantly lower in the anterior fissure group [167 cmH₂O (IQR 126–196) vs 205 cmH₂O (IQR 174–262), P = 0.004]. A history of obstetric trauma was significantly associated with anterior fissure location [OR 13.9 (95% CI 3.4–55.7)]. Conclusions Anterior anal fissures are associated with occult external anal sphincter injury and impaired external anal sphincter function compared with posterior fissures. These findings have implications for treatment, especially if a definitive procedure, such as lateral internal sphincterotomy, is considered.     

The effect of vaginal delivery on anal function

The commonest cause of faecal incontinence is considered to be childbirth. In this review we consider the available data on the prevalence of faecal incontinence in the community and the incidence of incontinence after childbirth. The results and implications of studies on childbirth using anal manometry, neurophysiological tests and anal ultrasound are discussed. The development of symptoms are more likely with a third degree tear and forceps delivery. Reduced resting and squeeze pressures are seen early after vaginal delivery with recovery noted with time. Reduced pressures have been seen in symptomatic and asymptomatic women and there is no correlation of the pressures with the presence or absence of a sphincter defect or evidence of pudendal neuropathy. Anal manometry can not be used as an indication of muscle or nerve injury. Both sphincter defects and evidence of pudendal neuropathy are common after vaginal delivery but these are not necessarily associated with symptoms. It is suggested that such occult sphincter injuries may go on to be symptomatic in later life. The number of these injuries, however, is far greater than the documented prevalence of incontinence in the community, and hence many must remain asymptomatic. Their true clinical significance remains uncertain.     

The role of pelvic floor denervation in the aetiology of idiopathic faecal incontinence

Weakness of the muscles of the pelvic floor and external anal sphincter may in theory be caused by a traction injury to the pelvic nerves incurred as a result of the excessive perineal descent that accompanies straining in the descending perineum syndrome (DPS). To investigate the role of this weakness in the aetiology of idiopathic faecal incontinence (IFI), measurements of perineal position, puborectalis mean fibre density (MFD), anal canal pressures, rectal sensation, capacity, and compliance were made in continent (DPS alone, n = 20) and incontinent (DPS + I, n = 19) patients with DPS, and a group of age and sex matched control subjects (n = 20). Perineal descent on straining was greater in DPS alone than in DPS + I. Puborectalis MFD was raised by similar degree in both DPS groups compared with the control subjects, and external anal sphincter function, assessed as voluntary squeeze pressure, was impaired by similar degree in DPS + I and DPS alone compared with the control subjects. Maximal basal anal canal pressure and rectal compliance were significantly reduced in DPS + I compared with DPS alone and the control subjects. Thus IFI did not result from progression of neurogenic muscle weakness, but occurred when there was also diminished internal anal sphincter tone and reduced rectal compliance.     

The use of a balloon catheter to improve evaluation in anorectal manometry

The squeeze pressure in the anal canal reflects the contribution of the external anal sphincter and is normally assessed manometrically by asking patients to contract their anal muscles. However, this is an artificial situation as normally the external sphincter contracts to retain rectal content. Some patients with normal anal sphincter anatomy and innervation record low squeeze pressures suggesting that the concept of voluntary squeeze is foreign. The aim of this study was to examine whether squeezing to retain a balloon mimics the physiology of defaecation more accurately. Patients undergoing routine anorectal manometry testing had in addition the inflation of a balloon catheter to the volume of the first and sustained sensation to simulate a faecal bolus within the rectum. The patient was asked to retain it when the balloon was subjected to gentle traction, thus contracting their anal sphincter to prevent passage of the balloon. Squeeze pressure was measured in response to voluntary contraction, the pressure generated to retain the balloon, then voluntary contraction again. Eighteen women and 2 men were tested. The median maximal squeeze pressures with the routine assessment was 131.0 cmH2O. This increased to 210.0 cmH2O when the patients attempted to retain the balloon and fell to 165.4 cmH2O when patients were reassessed with voluntary squeeze postintervention. 15 of the patients improved their squeeze pressures with traction on the balloon. External anal sphincter contraction is difficult for some patients to perform on request. With traction on a balloon catheter anal squeeze pressures improved in most patients. This indicates that many patients perform maximal anal squeeze pressures better once that muscle group has been tested in a more normal physiological function. This simple technique could improve the accuracy of anorectal manometry results and evaluation in a larger population of symptomatic patients is warranted.     

Late functional adaptation after colectomy, mucosal proctectomy, and ileal pouch-anal anastomosis

Ileal pouch-anal anastomosis (IPAA) is currently an alternative to proctocolectomy and ileostomy for patients with ulcerative colitis or familial polyposis. Some studies have suggested significant anal sphincter damage after mucosal proctectomy. Our aim was to assess prospectively late sphincter function after IPAA. In 250 patients, anorectal pressures were assessed with a pneumohydraulic perfused catheter manometry system. Each patient underwent colectomy, mucosal proctectomy, ileoanal anastomosis of a 15 cm ileal J-pouch, and loop ileostomy. Eight weeks after IPAA, anal manometry was repeated, and the ileostomy was closed. Manometry was repeated at yearly intervals. A decline in resting tone of the anal sphincter occurred early after IPAA with a gradual recovery toward control. External sphincter squeeze after pressures were not affected by IPAA and steadily increased to 8 years after operation. During this time, a progressive increase in J-pouch capacity was noted, and 24-hour stool frequency declined from 7.9 +/- 0.3 stools to 6.5 +/- 0.3 stools (p less than 0.05). We conclude that mucosal proctectomy results in internal anal sphincter trauma but is associated with long-term sphincter recovery, coupled with a significant improvement in external sphincter capacity, ileal pouch volume, and stool frequency.