Combining the strength-duration curve of the external anal sphincter with manometry for the assessment of faecal incontinence

BACKGROUND: The strength-duration curve of a muscle is thought to be a measure of its innervation. This study was designed to evaluate the ability of the strength-duration curve of the external anal sphincter to discriminate between controls and patients with faecal incontinence. METHODS: Forty-three women with faecal incontinence due to sphincter weakness were studied together with 45 age-matched women with no disorders of defaecation. Strength-duration curves of the external anal sphincter and anorectal manometry were recorded for all subjects with the additional measurement of pudendal nerve terminal motor latency in the incontinent group. RESULTS: Logistic regression was performed using resting and voluntary squeeze pressures and current strengths at 28 different pulse durations to develop a predictive equation for incontinence. Only currents at 1 and 6 ms were significant predictors. When anorectal manometry data were included, only the current required to elicit contraction at 1 ms was necessary. The following regression equation can be applied to predict continence in this population with a sensitivity of 95 per cent and a specificity of 100 per cent: logit(P)=4.1605-(0.0559 x squeeze pressure)-(0.1755 x resting pressure)+0.8622I(1 ms). A negative value indicates continence. CONCLUSION: The strength-duration curve, when used in conjunction with anorectal manometry, may have a role in the investigation of faecal incontinence.     

HLA-DRB1 alleles and beta 2 glycoprotein I-dependent anticardiolipin antibodies in Japanese patients with systemic lupus erythematosus

PURPOSE: This study was designed to evaluate the anatomic and functional consequences of lateral internal sphincterotomy in patients who developed anal incontinence and in matched controls. METHODS: The study includes 13 patients with anal incontinence after lateral internal sphincterotomy and 13 controls who underwent the same operation and were continent and satisfied with the results of the procedure. Patients underwent clinical evaluation, anorectal manometry, pudendal nerve terminal motor latency testing, and endoanal ultrasonography. RESULTS: Sphincterotomies were longer in incontinent patients (75 vs. 57 percent), but the resting pressure and length of the high-pressure zone were not different between groups. Surprisingly, maximum voluntary contraction was higher in incontinent patients than in continent controls (136 vs. 100 mmHg). Rectal sensation and pudendal nerve terminal motor latency were similar in both groups. The defect in the internal sphincter was wider in incontinent patients than in continent controls (17.3 vs. 14.4 mm), but these differences were not statistically significant. The thickness of the internal sphincter measured by endoanal ultrasound was identical in both groups, but the external sphincter was thinner in incontinent patients both at the site of the sphincterotomy (6.8 vs. 8.1 mm) and in the posterior midline (7.1 vs. 8.6 mm). CONCLUSIONS: Anal incontinence after lateral internal sphincterotomy is directly related to the length of the sphincterotomy. Whether secondary to preoperative sphincter abnormality or the result of lateral internal sphincterotomy, the external sphincter is thinner in incontinent patients than in continent controls.     

Third-degree obstetric perineal tear: long-term clinical and functional results after primary repair

BACKGROUND: This study was designed to investigate the long-term clinical and anorectal functional results after primary repair of a third-degree obstetrical perineal rupture. METHODS: One hundred and fifty-six consecutive women who had a primary repair of a third-degree perineal rupture were sent a questionnaire and asked to undergo anorectal function testing (anal manometry, anorectal sensitivity, anal endosonography and pudendal nerve terminal motor latency (PNTML)) RESULTS: Some 117 women (75 per cent) responded. Anal incontinence was present in 47 women (40 per cent); however, in most cases only mild symptoms were present. In 40 women additional anorectal function tests were performed and compared with findings in normal controls. Mean(s.d.) maximum squeeze pressure (31(15) versus 63(17) mmHg, P< 0.001) was decreased and first sensation to filling of the rectum (88(47) versus 66(33) ml, P=0.03) and anal mucosal electrosensitivity (4.7(1.7) versus 2.5(0.8) mA, P=0.003) were increased compared with values in normal controls. In 35 women (88 per cent) a sphincter defect was found with anal endosonography. Factors related to anal incontinence were the presence of a combined anal sphincter defect (relative risk (RR) 1.7 (95 per cent confidence interval (c.i.) 1.1-2.8)) or subsequent vaginal delivery (RR 1.6 (95 per cent c.i. 1.1-2.5)). CONCLUSION: Anal incontinence prevails in 40 per cent of women 5 years after primary repair of a third-degree perineal rupture. The presence of a combined sphincter defect or subsequent vaginal delivery increase the risk of anal incontinence.     

Pudendal nerve terminal motor latency influences surgical outcome in treatment of rectal prolapse

PURPOSE: This study was undertaken to document the effect of pudendal nerve function on anal incontinence after repair of rectal prolapse. METHODS: Patients with full rectal prolapse (n = 24) were prospectively evaluated by anal manometry and pudendal nerve terminal motor latency (PNTML) before and after surgical correction of rectal prolapse (low anterior resection (LAR; n = 13) and retrorectal sacral fixation (RSF; n = 11)). RESULTS: Prolapse was corrected in all patients; there were no recurrences during a mean 25-month follow-up. Postoperative PNTML was prolonged bilaterally (> 2.2 ms) in six patients (3 LAR; 3 RSF); five patients were incontinent (83 percent). PNTML was prolonged unilaterally in eight patients (4 LAR; 4 RSF); three patients were incontinent (38 percent). PNTML was normal in five patients (3 LAR; 2 RSF); one was incontinent (20 percent). Postoperative squeeze pressures were significantly higher for patients with normal PNTML than for those with bilateral abnormal PNTML (145 vs. 66.5 mmHg; P = 0.0151). Patients with unilateral abnormal PNTML had higher postoperative squeeze pressures than those with bilateral abnormal PNTML, but the difference was not significant (94.8 vs. 66.5 mmHg; P = 0.3182). The surgical procedure did not affect postoperative sphincter function or PNTML. CONCLUSION: Injury to the pudendal nerve contributes to postoperative incontinence after repair of rectal prolapse. Status of anal continence after surgical correction of rectal prolapse can be predicted by postoperative measurement of PNTML.     

Effect of a novel prosthetic anal neosphincter on human colonic blood flow

BACKGROUND: An artificial anal sphincter has been developed which aimed to simulate the normal physiology of the anorectum. As a prelude to human implantation the present study reports the effect of inflation of this device on colonic perfusion in patients undergoing colectomy, which was assessed by using a laser Doppler scanner. METHODS: Eleven patients (median age 49.8 (range 24.3-78.7) years) were studied. Five patients had inflammatory bowel disease (IBD). The neosphincter was placed around the bowel and progressively inflated. The model was designed so that blood flow changes to the colon under the neosphincter would be reflected in the distal segment of the bowel, which could be scanned by the laser Doppler scanner. RESULTS: The blood flow in the colon distal to the device was significantly higher in patients with IBD (mean(s.e.m.) 288.6(71.9) versus 211.1(57.6) perfusion units; P < 0.001). The mean(s.e.m.) 'biological zero' value was 46(14) perfusion units. Blood flow distal to the neosphincter decreased progressively with increased sphincteric compression by 0.66 per cent per mmHg applied pressure in controls and 0.35 per cent per mmHg in patients with IBD (P < 0.05). CONCLUSION: These results suggest that at the planned operating occlusion pressure (less than 45 mmHg) this neosphincter should not put the vascularity of the human colon at risk.     

Gluteus maximus augmentation for the treatment of fecal incontinence

Fecal incontinence is a devastating problem for school-aged children and adults. Medical and biofeedback therapies are unsuccessful in most patients who have severely defective internal and external sphincters. Continued fecal incontinence frequently leads to social isolation and withdrawal. Gluteus maximus augmentation of the sphincter mechanism is one surgical method for treating fecal incontinence. The authors present their results with gluteus maximus augmentation of the anal sphincter and describe patient selection criteria. From 1992 through 1996, seven patients underwent gluteus maximus augmentation of the anal sphincter for fecal incontinence. Six of these patients were children 5 to 6 years of age who had major deficiencies of their anorectal sphincter demonstrated by manometry. One patient was a 56-year-old adult woman who had acquired idiopathic fecal incontinence. Four of the six children (67%) had imperforate anus and two had cloacal anomalies (33%). The augmentation was performed in three stages. A sigmoid-end colostomy with a Hartman's pouch was followed 1 month later by rotation of a portion of the gluteus maximus for anorectal sphincter augmentation. A colostomy take down was performed 2 to 4 months later. All patients underwent dilatation after sphincter augmentation and were taught muscle exercises for using their neosphincter during the period before colostomy take down. Four of six children and the adult are continent postoperatively (71%). Both patients who remain incontinent are unable to sense rectal distention clinically or on anal manometric analysis but have excellent voluntary sphincter tone. Fecal incontinence can be successfully treated with gluteus maximus augmentation in carefully selected patients. Patients unable to sense rectal distension are unlikely to benefit from this procedure. The presence of a rectal reservoir and a skin-lined anal canal also appear to be important in attaining fecal continence.     

Anal and urinary incontinence after obstetric anal sphincter rupture]

The aim of the study was to assess the long term impact of obstetric anal sphincter rupture on the frequency of anal and urinary incontinence, and identify factors to predict patients at risk. In 94 consecutive women who had sustained an obstetric anal sphincter rupture, anal manometry, anal sphincter electromyography and pudendal nerve terminal motor latency at three months post partum was performed. A questionnaire regarding incontinence was sent between two to four years post partum. Forty-two percent of responders had anal incontinence, 32% had urinary and anal incontinence. Overall, 56% of the women had incontinence symptoms. The occurrence of anal incontinence was associated with pudendal nerve terminal motor latencies > 2.0 milliseconds and the occurrence of urinary incontinence was associated with the degree of rupture, the use of vacuum extraction and previous presence of urinary incontinence. Thirty-eight percent of the women with incontinence wanted treatment, but only a few had sought medical advice.     

Metabolism of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in isolated rat lung and liver

PURPOSE: Assessment of sustained voluntary contraction of the external sphincter is helpful in evaluating the patient who has a defecation disorder on presentation. A new index of external sphincter function is described. METHOD: A prospective registry of patients referred for computerized anal manometry using standard protocols was reviewed. Patients were grouped by primary symptoms; those with overlapping complaints were excluded. The rate of fatigue, defined as the change in stationary squeeze over a 40-second period of voluntary contraction, was calculated by linear regression analysis. Fatigue rate index, a calculated measure of time necessary for the external sphincter to become completely fatigued, was determined to permit comparison of external sphincter fatigue in patients with different complaints. RESULTS: Twenty-six healthy volunteers (15 women; mean age, 45 years), 33 patients with a primary complaint of anal seepage (13 women; mean age, 53 years), 75 patients with gross incontinence (61 women; mean age, 53 years), and 49 patients with severe constipation (41 women; mean age, 45 years) were evaluated. Mean resting and squeeze pressures were 55 mmHg and 107 mmHg for volunteers, 37 mmHg and 97 mmHg for patients with seepage, 30 mmHg and 49 mmHg for incontinent patients, and 56 mmHg and 93 mmHg for constipated patients. Pudendal neuropathy, as evidenced by a prolonged pudendal nerve terminal motor latency (> 2.4 ms), was identified in 13 percent of volunteers, 32 percent of patients with seepage, 54 percent of incontinent patients, and 38 percent of constipated patients. Mean fatigue rate index was 3.3 minutes for volunteers, 2.3 minutes for seepage patients, 1.5 minutes for incontinent patients, and 2.8 minutes for constipated patients. Compared with volunteers and patients with seepage, the incontinent patients had a significantly shorter fatigue rate index (P < 0.05; Student's t-test), which was independent of the variations in resting pressure (P < 0.05; two-way analysis of variance). CONCLUSION: The external anal sphincter is normally subject to fatigue. Patients with worsening degrees of incontinence have a predictably lower fatigue rate index. Fatigue rate index is a simple measure of external sphincter integrity, which may be used in assessment of sphincter function and future treatment protocols.     

Role of pudendal nerve terminal motor latency assessment in constipated patients

The importance of pudendal nerve terminal motor latency assessment for the evaluation of incontinence is well established. However, its role in constipated patients remains unclear. PURPOSE: The purpose of the present study was to assess the incidence of pudendal neuropathy in constipated patients and its correlation with others variables including age, sex, anal pressures, and anal electromyography. RESULTS: From 1988 to 1993, 161 patients with chronic constipation underwent pudendal nerve terminal motor latency assessment, anal electromyography, and anal manometry. The overall incidence of pudendal neuropathy was 23.6 percent; females and males had a similar incidence (24 percent vs. 23 percent, respectively; P > 0.05). Patients over 70 years old had a significantly higher incidence of pudendal neuropathy than did patients under 70 years (37 percent vs. 12 percent, respectively; P < 0.01). Patients with paradoxical puborectalis contraction on anal electromyographic assessment had a higher incidence of bilateral neuropathy, paradoxical puborectalis contraction (+)23 percent vs. paradoxical puborectalis contraction (-)8 percent, P < 0.05. Patients with pudendal neuropathy also had a higher incidence of decreased motor units potential recruitment than did patients without pudendal neuropathy (31.5 percent vs. 17 percent, respectively; P > 0.05). CONCLUSIONS: Pudendal nerve terminal motor latency assessment was able to detect unsuspected pudendal neuropathy in 24 percent of patients. This finding correlated with age and with the presence of paradoxical puborectalis contraction but not with manometric anal pressures, motor unit potentials recruitment, or the presence of polyphasia. However, the often espoused relationship between pudendal latency and external sphincter function could not be demonstrated.     

Pelvic floor function in multiple sclerosis

The aim of this study was to define pelvic floor function in patients with multiple sclerosis and bowel dysfunction, either incontinence (MSI) or defecation difficulties without incontinence (MSC). Normal controls and patients with idiopathic neurogenic faecal incontinence without multiple sclerosis (FI, disease controls) were also studied. Thirty eight multiple sclerosis patients (20 incontinent, 18 incontinent) 73 normal controls, and 91 FI patients were studied. The FI group showed the characteristic combined sensorimotor deficit previously described in these patients of low resting and voluntary contraction and pressures, increased sensory threshold to mucosal stimulation, and increased pudendal nerve terminal motor latencies and fibre densities. MSI patients had significantly lower anal resting pressures (80 (30-140) cm H2O, median (range) v 98 (30-200), normal controls, p = 0.002) and both MSC and MSI patients had significantly lower anal maximum voluntary contraction pressures (65 (0-260) cm H2O, MSC and 25 (0-100), MSI v 120 (30-300), normal controls, p = < 0.0004) and higher external anal sphincter fibre densities (1.7 (1.1-2.6), MSC and 1.7 (1.1-2.4), MSI v 1.5 (1.1-1.75), normal controls, p < 0.006) compared with normal controls but pudendal nerve terminal motor latencies were similar and no sensory deficit was found. This contrasted with the idiopathic faecal incontinent patients who, in addition to significantly higher fibre densities (1.8 (1.1-3), p = 0.001) had increased pudendal latencies (2.5 (1.1-5.5) mS v 2.08 (1.4-2.6), p = 0.001) compared with normal controls. The idiopathic faecal incontinent group had significantly lower resting anal pressures (50 (10-160) cm H2O, p=0.02) than the MSI group. Comparison with the incontinent and continent multiple sclerosis groups showed that incontinence was associated with lower voluntary anal contraction pressures (25 (0-100) v 65 (0-260), p=0.03) but that there were no other differences between these two groups. Pelvic floor function is considerably disturbed in multiple sclerosis, showing muscular weakness with preservation of peripheral motor nerve conduction, providing indirect evidence that this is mainly a result of lesions within the central nervous system.     

Anorectal function in patients with complete rectal prolapse. Differences between continent and incontinent individuals

AIMS: A study is made of the alterations in anorectal physiology among rectal prolapse patients, evaluating the differences between fecal continent and incontinent individuals. PATIENTS AND METHODS: Eighteen patients with complete rectal prolapse were divided into two groups: Group A (8 continent individuals) and Group B (10 incontinent women), while 22 healthy women were used as controls (Group C). Clinical exploration and perineal level measurements were performed, along with anorectal manometry, electrophysiology, and anorectal sensitivity to electrical stimuli. RESULTS: The main antecedents of the continent subjects were excess straining efforts, while the incontinent women presented excess straining and complex deliveries. Pathological perineal descent was a frequent finding in both groups, with a hypotonic anal canal at rest (p < 0.001 vs controls) and at voluntary squeezing (p < 0.001 vs controls). In turn, the incontinent patients exhibited a significantly lower anal canal pressure at rest than the continent women (p < 0.05). There were no significant differences between Groups A and C in terms of pudendal motor latency, though latency was significantly longer in Group B than in the controls (p < 0.01). Moreover, pudendal neuropathy was more common, severe and often bilateral in Group B. There were no differences in rectal sensation to distention or in terms of the volumes required to relax the internal anal sphincter. In turn, both prolapse groups exhibited diminished anal canal and rectal sensitivity to electrical stimuli. CONCLUSIONS: Patients with rectal prolapse exhibit a hypotonic anal canal at rest, regardless of whether they are continent to feces or not. Continent patients have less pudendal neuropathy and therefore less pressure alterations at voluntary sphincter squeeze than incontinent individuals.     

MR imaging of the anal sphincter in multiparous women using an endoanal coil: correlation with in vitro anatomy and appearances in fecal incontinence

OBJECTIVE: The aim of this study was to correlate the components of the normal female anal sphincter seen on high-resolution MR images with the in vitro anatomy and to describe the change in appearances of these components in multiparous women with fecal incontinence. SUBJECTS AND METHODS: Ten asymptomatic female volunteers (32-72 years old; mean, 54 years old) and 22 women with fecal incontinence were studied. In six patients (26-68 years old; mean, 49 years old) fecal incontinence began immediately after childbirth; in the remaining 16 patients (45-77 years old; mean, 58 years old) fecal incontinence developed 15- 30 years after childbirth. In the latter group of patients, terminal motor latencies of the pudendal nerve were measured. Imaging was done on a 0.5-T Picker Asset unit and on a 1.0-T Picker HPQ unit. A saddle geometry endoanal receiver coil was used for all imaging. T1-weighted spin-echo (720-820/20 [range of TR/TE]), T2-weighted spin-echo (2500/80 [TR/TE]), fast spin-echo (4500/96 [TR/ effective TE]), and short inversion time inversion recovery (2500/80 [TR/TE]; inversion time, 107 msec) MR images were obtained in transverse, coronal oblique, and sagittal planes. Images were assessed for integrity of the sphincter components. A nonpaired separate-variance t test was used to compare thickness of individual muscle components between patients with delayed-onset fecal incontinence and asymptomatic age-matched volunteers. Degree of muscle atrophy was correlated with degree of delay in the terminal motor latency of the pudendal nerve. RESULTS: The high resolution obtained with an endoanal coil allowed differentiation of the various muscle components of the anal sphincter complex. The internal sphincter was seen as a ring of homogeneously high signal intensity with a low-signal-intensity rim that was rich in collagen and contained neurovascular bundles. The external anal sphincter, which had low signal intensity on T1- and T2-weighted images, was shown as three components: subcutaneous, superficial, and deep. In six patients who had fecal incontinence that began immediately after childbirth, endoanal MR imaging revealed the site and extent of a tear. All tears were confirmed at surgery. In the 16 patients who had fecal incontinence that began several years after childbirth, atrophy of the external sphincter was revealed in all cases in the superficial and deep components. The internal sphincter remained normal. However, we found that the degree of atrophy of individual components of the external sphincter did not correlate with the degree of delay in pudendal nerve conduction. CONCLUSION: MR imaging with an endoanal coil reveals the integrity and bulk of individual muscle components of the anal sphincter in multiparous women with fecal incontinence.     

On the surgical treatment of refractory epilepsy in tuberous sclerosis complex

Using the pig as a model, it was shown that stimulation of the distal nerve ending of the pudendal nerve leads to the isolated stimulation of the external anal sphincter muscle. No difference in pressure response was noted after application of between 0.5 and 1.5 mA unilateral or bilateral stimulation. Major advantages observed using between 1.5 and 2.5 mA bilateral stimulation; with a stimulation between 2.0 and 2.5 mA the pressure response was twice as high compared to unilateral stimulation. Continuous stimulation of the striated anal sphincter muscle leads to fatigue, reaching 50% fatigue after a median time between 40-90 s. In cyclic stimulation (alternation every 15 s, duration 20 min) a fatigue reaction was also seen. The peak pressure decreased after 20 min for a median of 11%, the final pressure was lowered in 15% following a logarithmic curve pattern. The experimental application of variable impulse ranges also caused pressure differences. Increasing the impulse range from 200 to 450 microseconds (peak pressure) vs. 400 microseconds (final pressure) resulted in a statistically significant pressure increase. Therefore, it was proven that selective stimulation of the external anal sphincter muscle can lead to a transient pressure increase, which possibly improves fecal continence.     

Polymerase chain reaction (PCR) and its possible applications in diagnosis of infection in ophthalmology

Fecal incontinence resulting from pudendal canal syndrome has been treated by pudendal canal decompression (PCD) with satisfactory results. Considering the possible difficulty in exposing the pudendal canal and nerve by the open method, laparoscopic PCD was practiced in 9 women aged between 37 and 52 years. They were complaining of fecal incontinence; urinary stress incontinence was an additional complaint in 4/9 women. Neurologic, manometric, and EMG studies confirmed the diagnosis of pudendal canal syndrome. For laparoscopic PCD a 1-cm incision lateral to the anal orifice was performed. A balloon dilator was introduced in the ischiorectal fossa (IRF) to create a working space, and CO2 was insufflated. Under the guidance of a laparoscope, the IRF was entered and the inferior rectal nerve identified and followed to the pudendal canal. The latter was split open, releasing the pudendal nerve into the IRF. Fecal control was achieved in 7/9 patients and urinary control in 2/4. Fecal and urinary control were associated with improvement in perianal sensation, rectal neck pressure, EMG of external anal sphincter and levator ani muscle as well as in pudendal nerve terminal motor latency. Two women showed no improvement. Failure is suggested to be due to an advanced pudendal neuropathy. In conclusion, laparoscopic PCD is a simple, easy, and safe procedure. It allows for better exposure of the contents of the IRF than the open procedure, thus avoiding injury of the pudendal nerve and its branches during the performance of the PCD.     

Diagnosing anal sphincter injury with transanal ultrasound and manometry

PURPOSE: This study was undertaken to evaluate how well anorectal manometry and transanal ultrasonography diagnose anal sphincter injury. METHODS: Anorectal manometry and transanal ultrasonography were performed in 20 asymptomatic nulliparous women and 20 asymptomatic parous women, and the results were compared with those obtained in 31 incontinent women who subsequently underwent sphincteroplasty and, thus, had operatively verified anal sphincter injury. By using computerized manometry analysis, mean maximum resting and squeeze pressures, sphincter length, and vector symmetry were determined in all women. All transanal ultrasounds were interpreted blinded as to the patient's history, physical examination, and manometry results. RESULTS: Manometric resting and squeeze pressures were significantly higher in the asymptomatic nulliparous women than in the asymptomatic parous women, and both groups had significantly higher pressures than the incontinent women (P < 0.001). Anal sphincter length and vector symmetry index were significantly decreased in incontinent women compared with asymptomatic women (P < 0.01). Decreased resting and squeeze pressures suggestive of possible sphincter injury were found in 90 percent of incontinent women with known anal sphincter injury. Decreased anal sphincter length and vector symmetry were found in only 42 percent of women with known anal sphincter injury. Transanal ultrasound was able to identify 100 percent of the known sphincter injuries but also falsely diagnosed injury in 10 percent of the asymptomatic nulliparous women with intact anal sphincters. False identification of sphincter injury increased when transanal ultrasound scanning was performed proximal to the distal 1.5 cm of the anal canal. CONCLUSION: Although nonspecific, decreased resting and squeeze pressures were found in 90 percent of patients with anal sphincter injury. Decreased anal sphincter length or vector symmetry index were present in only 42 percent of patients with known sphincter injury. When limited to the distal 1.5 cm of the anal canal, transanal ultrasound identified all known sphincter injuries but falsely identified injury in 10 percent of women with intact anal sphincters. Transanal ultrasound in combination with decreased anal pressures correctly identified all intact sphincters and 90 percent of known anal sphincter injuries.     

Identification of two Y-box binding proteins that interact with the promoters of columbid annexin I genes

The aim of this study was to investigate the role of noradrenergic descending nervous pathways in external anal sphincter motility. For this purpose, the effects of intravenously injected adrenoceptor antagonist and agonist on the tonic electrical activity of this sphincter were studied in anesthetized cats. The effects of stimulating the region of the locus coeruleus and the effects of intravenous, intracerebroventricular and intrathecal injection of the above drugs on the electromyographic responses of this muscle to pudendal nerve stimulation were also investigated. The tonic sphincteric activity and the reflex response triggered by electrically stimulating pudendal afferent nerve fibers were inhibited by alpha1-adrenoceptor antagonist nicergoline and enhanced by alpha1-adrenoceptor agonist phenylephrine. Stimulation of the locus coeruleus area either inhibited or enhanced the reflex responses. Intracerebroventricular and intrathecal injection of the alpha2-adrenoceptor agonists, morphine and leu-enkephalin decreased the amplitude of these reflex responses. All the effects of opioids were blocked by naloxone and by spinalization performed at the cervical and lumbar levels. The direct response elicited by stimulating the sphincteric motor axons was not affected either by these drugs or by the brainstem stimulation. These results suggests the existence of a pontine neuronal network controlling the motility of the external anal sphincter via noradrenergic and opioid neurons.     

Immunochemical detection of cyclobutane thymine dimers in epidermal Langerhans cells of ultraviolet B-irradiated hairless mice

Integrity of sensory and motor function is essential in the maintenance of continence. The pudendal nerve assumes a central role being a mixed sensory and motor nerve. Neuropathic changes may therefore lead to incontinence and stretch injury to the pudendal nerve has been implicated as an aetiological factor. However pudendal neuropathy, altered anal sensation and perineal descent do not always correlate in the same patient. To investigate this further we evaluated the effect of a simulated defaecation strain on pelvic floor neurological function in a group of patients with constipation and incontinence. Pudendal nerve terminal motor latency (PNTML) and anal electrosensitivity (AS) were measured at rest and after a simulated defaecation strain of 1 minute. At rest PNTML correlated with AS (r = 0.461, P = 0.003). Twenty-five patients had perineal descent of more than 1 cm on straining, and 13 had descent below the ischial tuberosities. After 1 minute of straining AS was significantly (P < 0.001) blunted and PNTML was significantly (P < 0.001) prolonged both changes returning to normal after 3 minutes. AS was significantly (P = 0.01) more blunted in patients with perineal descent of more than 1 cm. PNTML was significantly (P = 0.01) more prolonged in patients with perineal descent of more than 2 cm. Age was significantly correlated with AS (r = 0.45, P = 0.004) and PNTML (r = 0.49, P = 0.002). Anal sensation and PNTML are acutely affected by defaecation straining, and changes may occur in patients without perineal descent. Functional changes occur equally in constipated and incontinent patients.     

Chronic anal fissure: results of the surgical treatment of 220 patients

Since results from non-surgical procedures designed for treatment of chronic anal fissure are still controversial, sphincterotomy remain as the "state of the art" therapy for this condition. In a retrospective basis, the authors intend to review results from treatment of chronic anal fissure in 220 patients who underwent surgical procedure between 1984 and 1995. Data from chart review included age, sex, location of the lesion at the canal anal, associated anorectal disease, delivered surgical technique and complications. Seventy per cent of the patients were male. Mean age was 37.1 years. Fissure was located at the posterior midline in 86.1%. Associated anorectal conditions occurred in 41.4%. Fissurectomy plus posterior sphincterotomy was the treatment of choice in 84.1%. Complications occurred in 5 (2.3%) cases. There were no incontinent patients. Mean follow-up was 2.6 years. The authors conclude that partial internal anal sphincter section produces excellent results in treatment of chronic anal fissure. Posterior sphincterotomy may persist effective and safe since continence impairment was not identified in the present study.     

Possible role of the autonomic nervous system in sphincter impairment after restorative proctocolectomy

Peroperative manometry was performed in 12 patients operated on with endoanal proctectomy and a hand-sewn pouch-anal anastomosis and in 12 in whom proctectomy was performed entirely from above, with the ileal pouch stapled to the top of the anal canal. Results from both groups showed that division of the superior rectal artery reduced the median (95 per cent confidence interval (c.i.)) resting anal pressure from 77.5 (69.9-83.3) mmHg to 64.5 (55.2-70.0) mmHg (P < 0.01). Complete rectal mobilization to the pelvic floor decreased resting pressure by an additional 22 per cent, to a median of 50.0 (95 per cent c.i. 40.1-53.5) mmHg (P < 0.01). After completion of anastomosis, irrespective of the operative technique used, a further decline in median pressure to 35.0 (95 per cent c.i. 26.0-47.7) mmHg could be demonstrated (P < 0.05). This study indicates that anal sphincter pressure is reduced to a similar extent after hand-sewn and stapled anastomoses. Injury to the autonomic nervous supply to the anal sphincter mechanism might be the major cause for this reduction.     

Salmonella penetration through eggshell associated with freshness of laid eggs and refrigeration

BACKGROUND: Significant associations between perineal descent and pudendal nerve latency have previously been described in fecally incontinent patients. This has led to the hypothesis that pelvic floor muscle and nerve injury initiated by childbirth might progress and cause fecal incontinence. PURPOSE: The study contained herein was undertaken to test whether changes in perineal position and pudendal nerve latency were associated in a population of healthy middle-aged women. METHODS: A cross-sectional study of 144 women were selected randomly from the Danish National Register; they had a mean age of 50 (range, 45-57) years and a mean parity of 2 (range, 0-6). Perineal position at rest and during simulated defecation and pudendal nerve terminal motor latency were measured. All examinations were performed by one of the authors (AMR) and without the knowledge of parity. RESULTS: The perineal position both at rest and during straining was significantly lowered, and the pudendal nerve terminal motor latency was significantly prolonged with increasing numbers of vaginal deliveries (data not shown). There was, however, no association between pudendal nerve terminal motor latency and perineal position at rest (correlation coefficient, r = -0.15, P = 0.1) or during simulated defecation (r = -0.08, P = 0.4). CONCLUSION: Small but significant effects of vaginal deliveries were detected in a random population of healthy perimenopausal women. However, because perineal descent and pudendal nerve latency were not associated, our findings do not support the hypothesis that damage induced by vaginal delivery to the pudendal nerves and pelvic floor will progress.