Anorectal pressure gradient and rectal compliance in fecal incontinence

To study whether anorectal pressure gradients discriminated better than standard anal manometry between patients with fecal incontinence and subjects with normal anal function, anorectal pressure gradients were measured during rectal compliance measurements in 36 patients with fecal incontinence and in 22 control subjects. Anal and rectal pressures were measured simultaneously during the rectal compliance measurements. With standard anal manometry, 75% of patients with fecal incontinence had maximal resting pressure within the normal range, and 39% had maximum squeeze pressure within the normal range. Anorectal pressure gradients did not discriminate better between fecal incontinence and normal anal function, since, depending on the parameters used, 61%–100% of the incontinent patients had anorectal pressure gradients within the normal range. Patients with fecal incontinence had lower rectal volumes than controls at constant defecation urge (median 138 ml and 181 ml, P<0.05) and at maximal tolerable volume (median 185 ml and 217 ml, P<0.05). We conclude that measurements of anorectal pressure gradients offer no advantage over standard anal manometry when comparing patients with fecal incontinence to controls. Patients with fecal incontinence have a lower rectal volume tolerability than control subjects with normal anal function. Accepted: 5 June 1998     

Rectal compliance in the assessment of patients with fecal incontinence

Rectal compliance (dV/dP) was studied in 31 patients with fecal incontinence, 8 patients with constipation, and 16 control subjects. Patients with fecal incontinence experienced a constant defecation urge at a lower rectal volume and also had a lower maximal tolerable volume and a lower rectal compliance than control subjects (median 126 vs. 155 ml, 170 vs. 220 ml, and 9 vs. 15 ml/mm Hg, respectively;tP <0.05). Constipated patients had a higher constant defecation urge volume and maximal tolerable volume than controls (median, 266 ml and 300 ml;P <0.05). There was no differences in the parameters between patients with idiopathic fecal incontinence and patients with incontinence of traumatic origin, indicating that a poorly compliant rectum in patients with fecal incontinence may be secondary to anal incontinence due to the lack of normal reservoir function.Reprints will not be available.     

Rectal Hypersensitivity Worsens Stool Frequency, Urgency, and Lifestyle in Patients With Urge Fecal Incontinence

PURPOSE Rectal sensory mechanisms are important in the maintenance of fecal continence. Approximately 50 percent of patients with urge incontinence have lowered rectal sensory threshold volumes (rectal hypersensitivity) on balloon distention. Rectal hypersensitivity may underlie the heightened perception of rectal filling; however, its impact on fecal urgency and incontinence is unknown. This study was designed to investigate the impact of rectal hypersensitivity in patients with urge fecal incontinence.METHODS Prospective and retrospective audit review of all patients (n = 258) with an intact native rectum referred to a tertiary colorectal surgical center for physiologic investigation of urge fecal incontinence during a 7.5-year period. Patients with urge fecal incontinence who had undergone pelvic radiotherapy (n = 9) or rectal prolapse (n = 6) were excluded.RESULTS A total of 108 of 243 patients (44 percent) were found to have rectal hypersensitivity. The incidence of anal sphincter dysfunction was equal (90 percent) among those with or without rectal hypersensitivity. Patients with urge fecal incontinence and rectal hypersensitivity had increased stool frequency (P < 0.0001), reported greater use of pads (P = 0.003), and lifestyle restrictions (P = 0.0007) compared with those with normal rectal sensation, but had similar frequencies of incontinent episodes.CONCLUSIONS Urge fecal incontinence relates primarily to external anal sphincter dysfunction, but in patients with urge fecal incontinence, rectal hypersensitivity exacerbates fecal urgency, and this should be considered in the management and surgical decision in patients who present with fecal incontinence.Christopher L. H. Chan, F.R.C.S., is supported by a MRC Clinical Training Fellowship.     

Rectal Volume Tolerability and Anal Pressures in Patients With Fecal Incontinence Treated With Sacral Nerve Stimulation

Purpose Sacral nerve stimulation has proven to be a promising treatment for fecal incontinence when conventional treatment modalities have failed. There have been several hypotheses concerning the mode of action of sacral nerve stimulation, but the mechanism is still unclear. This study was designed to evaluate the results of rectal volume tolerability, rectal pressure-volume curves, and anal pressures before and six months after permanent sacral nerve stimulation and to investigate the mode of action of sacral nerve stimulation. Methods Twenty-nine patients with incontinence (male/female ratio = 6/23; median age, 58 (range, 29–79) years) underwent implantation of a permanent sacral electrode and neurostimulator after a positive percutaneous nerve evaluation test. Wexner incontinence score, rectal distention with thresholds for “first sensation,” “desire to defecate,” and “maximal tolerable volume,” rectal pressure-volume curves, anal resting pressure, and maximum squeeze pressure were evaluated at baseline and at six months follow-up. Results Median Wexner incontinence score decreased from 16 (range, 6–20) to 4 (range, 0–12; P < 0. 0001). Median “first sensation” increased from 43 (range, 16–230) ml to 62 (range, 4–186) ml (P = 0.1), median “desire to defecate” from 70 (range, 30–443) ml to 98 (range, 30–327) ml (P = 0.011), and median “maximal tolerable volume” from 130 (range, 68–667) ml to 166 (range, 74–578) ml (P = 0.031). Rectal pressure-volume curves showed a significant increase in rectal capacity (P < 0.0001). The anal resting pressure increased significantly from 31 (range, 0–109) cm H₂O to 38 (range, 0–111) cm H₂O (P = 0.045). No significant increase in maximum squeeze pressure was observed. Conclusions For patients with fecal incontinence successfully treated with sacral nerve stimulation, there was a significant increase in rectal volume tolerability and rectal capacity. A significant increase in anal resting pressure, but not in maximum squeeze pressure, was found. We suggest that sacral nerve stimulation causes neuromodulation at spinal level. Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005.     

The appreciation of rectal distention in fecal incontinence

The subjective response to rectal balloon sensation was assessed with anorectal manometry and pudendal nerve terminal motor latency measurement (PNTML) in three groups of patients. There were 37 healthy subjects, 54 patients with idiopathic fecal incontinence (IFI), and 36 with complete rectal prolapse and incontinence (CRP). There was no significant difference for any parameter of rectal balloon sensation between patients with IFI and normals. Patients with CRP differed only in onset (P=.001). The results show that the appreciation of rectal distention is maintained in IFI.     

Anorectal dysfunction and rectal prolapse in progressive systemic sclerosis

Our aim was to characterize the clinical spectrum of anorectal dysfunction among eight patients with progressive systemic sclerosis (PSS) who presented with altered bowel movements with or without fecal incontinence. The anorectum was assessed by physical examination, proctosigmoidoscopy, and anorectal manometry. There was concomitant involvement of the other regions of the digestive tract in all patients as determined by barium studies, endoscopy, or manometry: eight esophageal, three gastric, four small bowel, and two colonic. Seven patients had fecal incontinence, and four also had second-degree complete rectal prolapse. Abnormal anorectal function, particularly abnormal anal sphincter resting pressures, were detected in all patients; anal sphincter pressures were lower in those with rectal prolapse. Rectal capacity and wall compliance were impaired in seven of seven patients. Successful surgical correction of prolapse in three patients resulted in restoration of incontinence for six months and seven years in two of the three patients. We conclude that rectal dysfunction and weakness of the anal sphincters are important factors contributing, respectively, to altered bowel movements and fecal incontinence in patients with gastrointestinal involvement by PSS. Rectal prolapse worsens anal sphincter dysfunction and should be sought routinely as it is a treatable factor aggravating fecal incontinence in patients with PSS.This work was presented in part at the Annual Meeting of the American Gastroenterological Association, May 1992, and appears in abstract form in Gastroenterology 1992;102:A473.Supported in part by the General Clinical Research Center Grant 00585 from the National Institutes of Health.     

Abnormal visceral autonomic innervation in neurogenic faecal incontinence.

Changes of denervation in the anal sphincter striated and smooth muscle in patients with neurogenic faecal incontinence are well established. This study aimed to determine if there is also a more proximal visceral autonomic abnormality. Thirty women with purely neurogenic faecal incontinence (prolonged pudendal nerve latencies and an intact sphincter ring) and 12 patients with neuropathic changes together with an anatomical disruption were studied. Two control groups consisted of 18 healthy volunteer women and 17 women with normal innervation but an anatomically disrupted sphincter. Rectal sensation was assessed using balloon distension and electrical mucosal stimulation, and anal sensation by electrical stimulation. Rectal compliance was studied to determine whether sensory changes were primary or caused by altered rectal wall viscoelastic properties. Anal canal pressure changes in response to both rectal distension and rectal electrical stimulation were measured to assess the intrinsic innervation of the internal anal sphincter. Patients with neurogenic incontinence alone had impaired rectal sensation to distension (53.1 v 31.5 ml, p < 0.05, neurogenic v controls) and to electrical stimulation (24.4 v 14.8 mA, p < 0.005). Patients with neurogenic incontinence and sphincter disruption also showed impaired sensation compared with healthy controls (55.8 ml v 31.5 ml, p < 0.05 and 22.9 mA v 14.8 mA, p < 0.05). Patients with only a disrupted sphincter had normal visceral sensation to both types of testing. Both rectal compliance and the response of the internal anal sphincter to rectal distension and electrical stimulation were normal in all patient groups. This study suggests that there is a visceral sensory abnormality in patients with neurogenic incontinence which is not caused by altered rectal compliance. As evaluated in this study the intrinsic innervation of the internal anal sphincter is not affected in this process.     

Rectal compliance, capacity, and rectoanal sensation in fecal incontinence

OBJECTIVE: Assessments of the pathophysiology of fecal incontinence are skewed toward anal sphincter function; however, rectal compliance, rectoanal sensation and capacity may also be relevant. The aim of this study was to evaluate the usual and some novel diagnostic approaches in fecal incontinence. METHODS: In 22 unselected patients with fecal incontinence (21 F, 33-75 yr), we quantified: 1) symptoms, anorectal manometry, and anal ultrasound; 2) anal perception of temperature and light touch; 3) rectal sensitivity and compliance to distension; and 4) rectal reservoir function. Control values were obtained from two groups of 11 (seven F, 32-53 yr), and 32 (18 F, 19-44 yr) volunteers. RESULTS: Patients had urge (14), passive (four), or combined (four) fecal incontinence; symptoms were mild in three, moderate in nine, and severe in 10 patients. Most had low sphincteric pressures and ultrasonic abnormalities. Temperature perception was impaired (p < 0.05) in incontinent patients, to a greater extent in the proximal anal canal and in patients with passive, as opposed to urge, incontinence. Intraluminal pressures for sensations of rectal distension were lower in incontinent patients (p = 0.02). Artificial stools elicited sensations of rectal filling at lower volumes than did a barostat bag, and in patients with urge, as opposed to passive, incontinence. In patients and controls, the sensation of urgency was associated (r2 = 0.2, p < 0.01) with rectal compliance. CONCLUSIONS: We confirm that temperature sensation is impaired, and perception of rectal distension is not always reduced in fecal incontinence. Artificial stool tended to induce sensations at lower volumes than did balloon inflation. Altered sensory mechanisms may contribute to the pathophysiology of fecal incontinence.     

Preoperative Anal Manometry Predicts Continence After Perineal Proctectomy for Rectal Prolapse

Purpose This study examines whether preoperative anal manometry and pudendal nerve terminal motor latency predict functional outcome after perineal proctectomy for rectal prolapse. Methods All adult patients treated by perineal proctectomy for rectal prolapse from 1995 to 2004 were identified (N = 106). Forty-five patients underwent anal manometry and pudendal nerve terminal motor latency testing before proctectomy and they form the basis for this study. Results Perineal proctectomy with levatoroplasty (anterior 88.9 percent; posterior 75.6 percent) was performed in all patients, with a mean resection length of 10.4 cm. Four patients (8.9 percent) developed recurrent prolapse during a 44-month mean follow-up. Preoperative resting and maximal squeeze pressures were 34.2 ± 18.3 and 60.4 ± 30.5 mmHg, respectively. Pudendal nerve terminal motor latency testing was prolonged or undetectable in 55.6 percent of patients. Grade 2 or 3 fecal incontinence was reported by 77.8 percent of patients before surgery, and one-third had obstructed defecation. The overall prevalence of incontinence (77.8 vs. 35.6 percent, P < 0.0001) and constipation (33.3 vs. 6.7 percent, P = 0.003) decreased significantly after proctectomy. Patients with preoperative squeeze pressures >60 mmHg (n = 19) had improved postoperative fecal continence relative to those with lower pressures (incontinence rate, 10 vs. 54 percent; P = 0.004), despite having similar degrees of preoperative incontinence. Abnormalities of pudendal nerve function and mean resting pressures were not predictive of postoperative incontinence. Conclusions Perineal proctectomy provides relief from rectal prolapse, with good intermediate term results. Preoperative anal manometry can predict fecal continence rates after proctectomy, because patients with maximal squeeze pressures >60 mmHg have significantly improved outcomes. Supported exclusively using institutional funding. Presented at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005.     

What affects continence after anterior resection of the rectum?

Functional results after anterior rectal resections are commonly considered satisfactory but variable percentages of postoperative incontinence are often reported. Continence was evaluated after 20 low anterior resections (LAR) and 13 high anterior resections (HAR) by means of clinical assessment, anorectal manometry, and evacuation proctography. Whereas all HAR patients had perfect continence, 10 patients (50 percent of the LAR group had occasional episodes of soiling from liquid feces, 5 patients (25 percent had frequent soiling or occasional incontinence for solid feces, and 1 patient (5 percent had frequent solid stool loss requiring surgical treatment. Anal canal resting pressure at 3 and 4 cm from the anal verge was significantly lower in the LAR group (P<0.02 and P<0.05, respectively) than in the HAR group. However, the maximum voluntary contraction did not differ between the two groups. Rectoanal inhibitory reflex was found to be present in 17 of the 20 patients with LAR and in all patients with HAR. The volume at which the anal sphincter is continuously inhibited was significantly reduced in the LAR group (P<0.001). Also, the conscious rectal sensibility volumes were found to be significantly reduced for threshold, constant, and maximum tolerated volume. Threshold volume for internal sphincter relaxation was lower than the threshold volume for rectal sensation in some patients with LAR. This could allow postoperative fecal soiling. Rectal compliance was decreased (P<0.001) in the LAR group. Evacuation proctography, performed in six LAR patients affected by major soiling or solid stool loss, revealed an abnormal obtuse anorectal angle and pathologic lowering of the perineum at rest and during defecation. The concomitance of internal anal sphincter impairment, reduction in rectal compliance, and previous pelvic floor muscle damage are postulated as cause affecting continence in patients who underwent LAR.Read at the Congress on Colo-Rectal Disease Milan, Italy, June 29–30, 1989.     

Effect of Aging on Anorectal and Pelvic Floor Functions in Females

Purpose In females, fecal incontinence often is attributed to birth trauma; however, symptoms sometimes begin decades after delivery, suggesting that anorectal sensorimotor functions decline with aging. Methods In 61 asymptomatic females (age, 44 ± 2 years, mean ± standard error of the mean) without risk factors for anorectal trauma, anal pressures, rectal compliance, and sensation were assessed by manometry, staircase balloon distention, and a visual analog scale during phasic distentions respectively. Anal sphincter appearance and pelvic floor motion also were assessed by static and dynamic magnetic resonance imaging respectively in 38 of 61 females. Results Aging was associated with lower anal resting (r = −0.44, P < 0.001) and squeeze pressures (r = −0.32, P = 0.01), reduced rectal compliance (i.e., r for pressure at half-maximum volume vs. age = 0.4, P = 0.001), and lower (P ≤ 0.002) visual analog scale scores during phasic distentions at 16 (r = −0.5) and 24 mmHg (r = −0.4). Magnetic resonance imaging revealed normal anal sphincters in 29 females and significant sphincter injury, not associated with aging, in 9 females. The location of the anorectal junction at rest (r = 0.52, P < 0.001), squeeze (r = 0.62, P < 0.001), and Valsalva maneuver (r = 0.35, P = 0.03), but not anorectal motion (e.g., from resting to squeeze) was associated with age. Conclusions In asymptomatic females, aging is associated with reduced anal resting and squeeze pressures, reduced rectal compliance, reduced rectal sensation, and perineal laxity. Together, these changes may predispose to fecal incontinence in elderly females. Supported in part by Grants R01 HD38666, R01 HD41129, and R01 EB00212 (SJR) and General Clinical Research Center grant M01 RR00585 from the National Institutes of Health, U.S. Public Health Service. Presented at the meeting of the American Gastroenterological Association, Atlanta, Georgia, May 20 to 23, 2001. An erratum to this article is available at .     

Rectal tone and compliance affected in patients with fecal incontinence after fistulotomy

AIM: To investigate the anal sphincter and rectal factors that may be involved in fecal incontinence that develops following fistulotomy(FIAF).METHODS: Eleven patients with FIAF were compared with 11 patients with idiopathic fecal incontinence and with 11 asymptomatic healthy subjects(HS). All of the study participants underwent anorectal manometry and a barostat study(rectal sensitivity, tone, compliance and capacity). The mean time since surgery was 28 ± 26 mo. The postoperative continence score was 14 ± 2.5(95%CI: 12.4-15.5, St Mark's fecal incontinence grading system).RESULTS: Compared with the HS, the FIAF patients showed increased rectal tone(42.63 ± 27.69 vs 103.5 ± 51.13, P = 0.002) and less rectal compliance(4.95 ± 3.43 vs 11.77 ± 6.9, P = 0.009). No significant differences were found between the FIAF patients and the HS with respect to the rectal capacity; thresholds for the non-noxious stimuli of first sensation, gas sensation and urge-to-defecate sensation or the noxious stimulus of pain; anal resting pressure or squeeze pressure; or the frequency or percentage of relaxation of the rectoanal inhibitory reflex. No significant differences were found between the FIAF patients and the patients with idiopathic fecal incontinence.CONCLUSION: In patients with FIAF, normal motor anal sphincter function and rectal sensitivity are preserved, but rectal tone and compliance are impaired. The results suggest that FIAF is not due to alterations in rectal sensitivity and that the rectum is more involved than the anal sphincters in the genesis of FIAF.     

Anorectal sensory and motor function in neurogenic fecal incontinence. Comparison between multiple sclerosis and diabetes mellitus

We measured anorectal sensory and motor function in 11 patients with multiple sclerosis and fecal incontinence, 11 continent patients with multiple sclerosis, 10 diabetics with fecal incontinence, and 12 healthy control subjects. The threshold volume at which patients with multiple sclerosis and fecal incontinence experienced rectal sensation was higher than that in healthy controls (42.7 +/- 6.2 mL vs. 13.3 +/- 2.8 mL; P less than 0.01) and was similar to that in incontinent diabetics (36.5 +/- 5.7 mL). Patients with multiple sclerosis and incontinent diabetics also showed increased thresholds of phasic external sphincter contraction compared with controls (P less than 0.05). Diabetics with incontinence had reduced resting and maximal voluntary anal sphincter pressures compared with controls (P less than 0.05), whereas patients with multiple sclerosis and incontinence showed only decreased maximal voluntary anal sphincter pressures (P less than 0.01 vs. controls and diabetics). Incontinent patients with multiple sclerosis also required smaller volumes of rectal distention to inhibit internal sphincter tone compared with diabetics and controls (P less than 0.01). Decreased maximal voluntary squeeze pressures were less severe in continent patients with multiple sclerosis than in incontinent patients with multiple sclerosis. We conclude that impaired function of the external anal sphincter and decreased volumes of rectal distention to inhibit the internal anal sphincter or both may contribute to fecal incontinence in multiple sclerosis. In addition, increased thresholds of conscious rectal sensation in some incontinent patients with multiple sclerosis and diabetes mellitus may contribute to fecal incontinence by impairing the recognition of impending defecation.     

Viscous fluid retention: A new method for evaluating anorectal function

The ability to retain viscous fluid in the standing position was tested in 22 patients with fecal incontinence, 11 patients with constipation, and 26 control subjects. Viscous fluid was introduced into the rectum in increments of 50 ml. The examination was stopped when the patient complained of discomfort or the viscous fluid leaked. Eighteen of 22 patients with fecal incontinence leaked fluid, while none of the control subjects and only four of the constipated patients did so. Patients with fecal incontinence retained significantly less viscous fluid than did control subjects, whereas no difference was found between patients with constipation and control subjects. Rectal sensation from distention with air was tested in the patients as well as in the control group. The following volumes and pressures at each sensation were measured: 1) earliest defecation urge (EDU), 2) constant defecation urge (CDU), and 3) maximum tolerable volume (MTV). Patients with fecal incontinence had lower volumes than control subjects at all sensations, while patients with constipation had higher volumes at earliest defecation urge and at constant defecation urge. Rectal compliance was higher in patients with fecal incontinence than in control subjects, whereas patients with constipation did not differ from control subjects. Regression analysis showed a linear relationship between viscous fluid retention and the maximum tolerable volume and also between viscous fluid retention and rectal compliance. No difference in the ability to retain viscous fluid between male and female control subjects was found; regression analysis of viscous fluid retention in relation to age revealed decreasing volumes with increasing age. Day-to-day variation of the ability to retain viscous fluid was tested in eight persons, and reproducibility was found to be good.     

Results of neurophysiologic evaluation in fecal incontinence

PURPOSE: Several methods of neurophysiologic assessment exist in the investigation of patients with fecal incontinence. However, the clinical significance of the information gained is uncertain. The aim of this prospective study was to evaluate the results of pudendal nerve terminal motor latency and fiber density in relation to clinical variables and manometric measurements. METHODS: Seventy-two patients with fecal incontinence (63 women; mean age, 62; range, 24–81 years) responded to a bowel questionnaire and underwent anorectal manovolumetry, anal ultrasonography, defecography, and electromyography, including pudendal nerve terminal motor latency and fiber density. RESULTS: Pudendal neuropathy (pudendal nerve terminal motor latency >2.5 ms) was found in 46 percent and increased fiber density (>1.7) in 82 percent. Pudendal neuropathy and increased fiber density were most common in patients with rectal prolapse or intra-anal intussusception. No difference was seen concerning anal resting and incremental pressures, rectal compliance, rectal sensibility or severity of incontinence in patients with unilateral, bilateral, or marked (>4 ms) pudendal neuropathyvs. patients with normal pudendal nerve terminal motor latency. In contrast, patients with increased fiber density had lower incremental pressures (P<0.05) and stated decreased rectal sensibility (P<0.05) compared with those with normal fiber density. These differences were most pronounced in patients with neurogenic or idiopathic incontinence. CONCLUSIONS: Pudendal neuropathy and increased fiber density are common in patients with fecal incontinence. Fiber density but not pudendal nerve terminal motor latency was correlated with clinical and manometric variables. The severity of nerve injury correlated with anal motor and sensory function in patients with neurogenic or idiopathic incontinence. The routine use of pudendal nerve terminal motor latency in the assessment of patients with fecal incontinence can be questioned.Read at The American Society of Colon and Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington, D.C., May 1 to 6, 1999.     

Paradoxical high anal resting pressures in men with idiopathic fecal seepage

PURPOSE: Fecal incontinence has been a matter of concern for many years, but seepage is poorly understood, especially in men. METHODS: We compared the results of anorectal physiologic tests in a group of 16 male patients who complained of fecal soiling but had no previous history of anorectal surgery or disease and had normal clinical examinations with findings of 16 normal male controls. Physical examination and proctosigmoidoscopy were normal in each patient. RESULTS: Maximum anal resting pressure (median interquartile range) was 136 (120–145) cm H₂O in the “seepage” group and 104 (83–112) cm H₂O in controls (P<0.01). Inflation volumes at which patients and controls experienced rectal sensation were 45 (35–80) and 90 (75–100) ml of air, respectively (P<0.01). Maximum tolerated volumess in the rectum were 130 (85–180) ml of air in the seepage group and 190 (140–240) ml of air in controls (P<0.01). Median length of the anal sphincter was 3.75 (3.5–4) cm in patients and 3 (3–3.5) cm in controls (P<0.01). Maximum squeeze pressures, sensation in the anal canal, and sphincter relaxation in response to rectal distention were similar in the two groups. CONCLUSION: Male patients with “idiopathic” fecal seepage have a long anal sphincter with abnormally high resting tone.     

Preoperative Chemoradiation for Rectal Cancer Causes Prolonged Pudendal Nerve Terminal Motor Latency

Purpose A worsened anorectal function after chemoradiation for high-risk rectal cancer is often attributed to radiation damage of the anorectum and pelvic floor. Its impact on pudendal nerve function is unclear. This prospective study evaluated the short-term effect of preoperative combined chemoradiation on anorectal physiologic and pudendal nerve function. Methods Sixty-six patients (39 men, 27 women) with localized resectable (T3, T4, or N1) rectal cancer were included in the study. All patients received 45 Gy (1.8 Gy/day in 25 fractions) over five weeks, plus 5-fluorouracil (350 mg/m²/day) and leucovorin (20 mg/m²/day) concurrently on days 1 to 5 and 29 to 33. Patients who had rectal cancer with a distal margin within 6 cm of the anal verge had the anus included in the field of radiotherapy (Group A, n = 26). Patients who had rectal cancer with a distal margin 6 to 12 cm from the anal verge had shielding of the anus during radiotherapy (Group B, n = 40). The Wexner continence score, anorectal manometry and pudendal nerve terminal motor latency were assessed at baseline and four weeks after completion of chemoradiation. Results The median Wexner score deteriorated significantly (P < 0.0001) from 0 to 2.5 for both Groups A (range, 0–8) and B (range, 0–14). The maximum resting anal pressures were unchanged after chemoradiation. The maximum squeeze anal pressures were reduced (mean = 166.5–157.5 mmHg) after chemoradiation. This change was similar in both Groups A and B. Eighteen patients (Group A = 7, Group B = 11) developed prolonged pudendal nerve terminal motor latency after chemoradiation. These 18 patients similarly had a worsened median Wexner continence score (range, 0–3) and maximum squeeze anal pressures (mean = 165.5–144 mmHg). The results obtained were independent of tumor response to chemoradiation. Conclusions Preoperative chemoradiation for rectal cancer carries a significant risk of pudendal neuropathy, which might contribute to the incidence of fecal incontinence after restorative proctectomy for rectal cancer. Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005.     

Anorectal pressure gradient in patients with anal incontinence

Anorectal pressures in patients with fecal incontinence have been investigated. With anal manometry, 34 percent of patients with fecal incontinence had maximal resting pressure and 39 percent had maximal squeeze pressure within the normal range. When a pressure gradient was calculated as the pressure difference between maximal resting pressure and rectal pressuring during filling of a rectal balloon, patients with fecal incontinence could be better distinguished from controls: 20 percent of patients with fecal incontinence had values within the normal range when the rectal pressure at the earliest defecation urge was used (P <0.05), and 12 percent had values within the normal range when the rectal pressure at maximal tolerable volume was used (P <0.01). Anorectal pressure gradient measurements seem to distinguish patients with fecal incontinence from controls better than maximal resting pressure or maximal squeeze pressure alone.     

Effects of acute hyperglycaemia on anorectal motor and sensory function in diabetes mellitus.

AIMS: To determine the effects of acute hyperglycaemia on anorectal motor and sensory function in patients with diabetes mellitus. METHODS: In eight patients with Type 1, and 10 patients with Type 2 diabetes anorectal motility and sensation were evaluated on separate days while the blood glucose concentration was stabilized at either 5 mmol/l or 12 mmol/l using a glucose clamp technique. Eight healthy subjects were studied under euglycaemic conditions. Anorectal motor and sensory function was evaluated using a sleeve/sidehole catheter, incorporating a barostat bag. RESULTS: In diabetic subjects hyperglycaemia was associated with reductions in maximal (P<0.05) and plateau (P<0.05) anal squeeze pressures and the rectal pressure/volume relationship (compliance) during barostat distension (P<0.01). Hyperglycaemia had no effect on the perception of rectal distension. Apart from a reduction in rectal compliance (P<0.01) and a trend (P=0.06) for an increased number of spontaneous anal sphincter relaxations, there were no differences between the patients studied during euglycaemia when compared with healthy subjects. CONCLUSIONS: In patients with diabetes, acute hyperglycaemia inhibits external anal sphincter function and decreases rectal compliance, potentially increasing the risk of faecal incontinence.     

Long-Term Effect of Preoperative Radiation Therapy on Anorectal Function

Purpose Preoperative radiotherapy improves local control in rectal cancer treatment, but there are few reports on the influence of radiotherapy on anorectal function. The aim of the present study was to assess late effects of short-course, high-dose radiotherapy on anorectal function after low anterior resection for rectal cancer. Methods Sixty-four patients, randomized within the Stockholm Radiotherapy Trials and operated on with low anterior resection with or without preoperative radiotherapy (mean, 14 years), previously were followed up with quality-of-life questionnaires, clinical examination, anorectal manometry, and endoanal ultrasound. Twenty-one patients had received preoperative radiotherapy of the rectum and 43 patients had been treated with surgery alone. Results Impaired anorectal function was common after low anterior resection for rectal cancer and the risk was increased after radiotherapy. Irradiated patients had significantly more symptoms of fecal incontinence (57 vs. 26 percent, P = 0.01), soiling (38 vs. 16 percent, P = 0.04), and significantly more bowel movements per week (20 vs. 10, P = 0.02). At anorectal manometry, irradiated patients had significantly lower resting (35 mmHg vs. 62 mmHg, P < 0,001) and squeeze pressures (104 mmHg vs. 143 mmHg, P = 0.05). At endoanal ultrasound, irradiated patients had significantly more scarring of the anal sphincters (33 vs. 13 percent, P = 0.03). There were no significant differences in quality-of-life scores between irradiated and nonirradiated patients; however, patients with anal incontinence had significantly lower quality-of-life scores compared to continent patients. Conclusions Short-course radiotherapy, including the anal sphincters, impairs anorectal function and increases gastrointestinal symptoms permanently when the anal sphincters are irradiated. Supported by the The Swedish Cancer Society and the Stockholm Cancer Society. Study was conducted at the Karolinska and Danderyd Hospitals, Stockholm, Sweden. Presented at the Tripartite Colorectal Meeting, Dublin, Ireland, July 3 to 7, 2005. Reprints are not available.