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External Anal Sphincter (external + anal_sphincter)
Selected AbstractsComparison of the contractile properties, oxidative capacities and fibre type profiles of the voluntary sphincters of continence in the ratJOURNAL OF ANATOMY, Issue 3 2010Maria Buffini Abstract The external urethral sphincter (EUS) and external anal sphincter (EAS) are the principal voluntary striated muscles that sustain continence of urine and faeces. In light of their common embryological origin, shared tonic sphincteric action and synchronized electrical activity in vivo, it was expected that they would exhibit similar physiological and structural properties. However, the findings of this study using paired observations of both sphincters isolated from the rat show clearly that this is not the case. The anal sphincter is much more fatigable than the urethral sphincter. On completion of a fatigue protocol, the amplitude of the last twitch of the EAS had declined to 42 ± 3% of the first twitch, whereas the last twitch of the EUS was almost identical to that of the first (95 ± 3%). Immunocytochemical detection of myosin heavy-chain isoforms showed that this difference was not due to the presence of more slow-twitch oxidative type 1 fibres in the EUS compared with the EAS (areal densities 4 ± 1% and 5 ± 1%, respectively; P = 0.35). In addition, the fatigue difference was not explained by a greater contribution to force production by fast oxidative type 2A fibres in the urethral sphincter. In fact, the anal sphincter contained a higher areal density of type 2A fibres (56 ± 5% vs. 37 ± 4% in the EUS, P = 0.017). The higher oxidative capacity of the EUS, measured histochemically, explained its fatigue resistance. These results were surprising because the fatigue-resistant urethral muscle exhibited faster single-twitch contraction times compared with the anal sphincter (56 ± 0.87 ms vs. 72.5 ± 1.16 ms, P < 0.001). Neither sphincter expressed the type 2X myosin isoform but the fast-twitch isoform type 2B was found exclusively in the EUS (areal density 16 ± 2%). The type 2B fibres of the EUS were small (diameter 19.5 ± 0.4 ,m) in comparison to typical type 2B fibres of other muscles. As a whole the EUS is a more oxidative than glycolytic muscle. In conclusion, analysis of the twitch mechanics and fatigue of two sphincters showed that the EUS contained more fatigue-resistant muscle fibres compared with the EAS. [source] Correlation between gross anatomical topography, sectional sheet plastination, microscopic anatomy and endoanal sonography of the anal sphincter complex in human malesJOURNAL OF ANATOMY, Issue 2 2009S. Al-Ali Abstract This study elucidates the structure of the anal sphincter complex (ASC) and correlates the individual layers, namely the external anal sphincter (EAS), conjoint longitudinal muscle (CLM) and internal anal sphincter (IAS), with their ultrasonographic images. Eighteen male cadavers, with an average age of 72 years (range 62,82 years), were used in this study. Multiple methods were used including gross dissection, coronal and axial sheet plastination, different histological staining techniques and endoanal sonography. The EAS was a continuous layer but with different relations, an upper part (corresponding to the deep and superficial parts in the traditional description) and a lower (subcutaneous) part that was located distal to the IAS, and was the only muscle encircling the anal orifice below the IAS. The CLM was a fibro-fatty-muscular layer occupying the intersphincteric space and was continuous superiorly with the longitudinal muscle layer of the rectum. In its middle and lower parts it consisted of collagen and elastic fibres with fatty tissue filling the spaces between the fibrous septa. The IAS was a markedly thickened extension of the terminal circular smooth muscle layer of the rectum and it terminated proximal to the lower part of the EAS. On endoanal sonography, the EAS appeared as an irregular hyperechoic band; CLM was poorly represented by a thin irregular hyperechoic line and IAS was represented by a hypoechoic band. Data on the measurements of the thickness of the ASC layers are presented and vary between dissection and sonographic imaging. The layers of the ASC were precisely identified in situ, in sections, in isolated dissected specimens and the same structures were correlated with their sonographic appearance. The results of the measurements of ASC components in this study on male cadavers were variable, suggesting that these should be used with caution in diagnostic and management settings. [source] Neurophysiological testing in anorectal disordersMUSCLE AND NERVE, Issue 3 2006Jean-Pascal Lefaucheur MD, PhDArticle first published online: 15 JUL 200 Abstract The neurophysiological techniques currently available to evaluate anorectal disorders include concentric needle electromyography (EMG) of the external anal sphincter, anal nerve terminal motor latency (TML) measurement in response to transrectal electrical stimulation or sacral magnetic stimulation, motor evoked potentials (MEPs) of the anal sphincter to transcranial magnetic cortical stimulation, cortical recording of somatosensory evoked potentials (SEPs) to anal nerve stimulation, quantification of electrical or thermal sensory thresholds (QSTs) within the anal canal, sacral anal reflex (SAR) latency measurement in response to pudendal nerve or perianal stimulation, and perianal recording of sympathetic skin responses (SSRs). In most cases, a comprehensive approach using several tests is helpful for diagnosis: needle EMG signs of sphincter denervation or prolonged TML give evidence for anal motor nerve lesion; SEP/QST or SSR abnormalities can suggest sensory or autonomic neuropathy; and in the absence of peripheral nerve disorder, MEPs, SEPs, SSRs, and SARs can assist in demonstrating and localizing spinal or supraspinal disease. Such techniques are complementary to other methods of investigation, such as pelvic floor imaging and anorectal manometry, to establish the diagnosis and guide therapeutic management of neurogenic anorectal disorders. Muscle Nerve, 2005 [source] Standardization of anal sphincter electromyography: Utility of motor unit potential parametersMUSCLE AND NERVE, Issue 7 2001Simon Podnar MD Abstract Advanced electromyography systems offer quantitative analysis of a number of motor unit potential (MUP) parameters. However, only limited data are available on the diagnostic usefulness of these parameters. In the present study, we compared the sensitivities of MUP parameters in revealing "neuropathic" changes in the external anal sphincter (EAS) muscles in 56 patients examined 5,240 months after damage to the cauda equina or conus medullaris. Using multi-MUP analysis, 20 MUPs were obtained from patients' EAS muscles. Their MUP parameters were compared with normative data from 64 controls. The diagnostic sensitivities of mean values/"outliers" of MUP parameters for detecting neuropathic EAS muscles were calculated (area 25%/30%; number of turns 18%/29%; size index 13%/24%; thickness 18%/18%; amplitude 17%/17%; spike duration 20%/9%; duration 15%/12%; number of phases 15%/11%; and their combination 51%/52%). Altogether, the cumulative sensitivity of multi-MUP analysis using both mean values and "outliers" was 62%. The combination of MUP parameters improves the diagnostic yield of MUP analysis, but the influence on specificity remains unknown. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 946,951, 2001 [source] Supraspinal control of external anal sphincter motility: effects of vesical distension in humans and catsNEUROGASTROENTEROLOGY & MOTILITY, Issue 11 2006V. Vitton Abstract, A pontine centre located near the micturition centre controlling external anal sphincter (EAS) motility via noradrenergic neurones has been described in cats. The aim of this study was to determine (i) whether a similar centre controls EAS motility in humans and (ii) whether this centre is involved in vesico-sphincteric reflexes in cats and humans. The effects of an alpha-1-adrenoceptor antagonist (nicergoline) and those of vesical distension on the electrical activity of the EAS were studied in paraplegic and non-paraplegic volunteers. The effects of vesical distension by injecting saline at physiological levels on the responses of the EAS to pudendal nerve stimulation were investigated in intact cats and cats with nerve sections. In non-paraplegic subjects, nicergoline and vesical distension abolished the activity of the EAS. These effects were no longer observed in paraplegic patients. In cats, vesical distension inhibited the reflex response of the EAS to pudendal nerve stimulation. This vesico-sphincteric reflex, which was no longer observed in spinal animals, persisted after nicergoline injection. These findings indicate that in humans, there exists a supra-spinal centre facilitating the tonic activity of the EAS via noradrenergic neurones not involved in the inhibitory vesico-sphincteric reflex. [source] Ano-rectal motility responses to pelvic, hypogastric and pudendal nerve stimulation in the Göttingen minipigNEUROGASTROENTEROLOGY & MOTILITY, Issue 2 2006I. S. Andersen Abstract, We investigated the effect of efferent stimulation of the pelvic (PN), hypogastric (HGN) and pudendal (PuN) nerves on ano-rectal motility in Göttingen minipigs using an impedance planimetry probe. Changes in the rectal cross-sectional area (CSA) at five axial positions and pressures in the rectum and anal canal were investigated simultaneously. Pelvic nerve stimulation elicited a CSA decrease in the proximal part of the rectum and a simultaneous CSA increase in its distal part. Anal pressure also decreased. Hypogastric nerve and PuN stimulation elicited an increase in anal pressure, but no rectal response. Severing the HGN produced a persistent reduction in resting anal pressure, but no change was observed when the PN and the PuN were severed. Stimulation of the distal part of all three nerves produced a persistent response. Administration of phentolamine and pancouronium eliminated the response to stimulation of the HGN and the PuN, respectively. Conclusion:, Rectal responses to PN stimulation vary more than previously suggested. The HGN has an excitatory effect on the internal anal sphincter, and the PuN on the external anal sphincter. However, the PuN plays no major role in maintaining basal anal pressure. [source] Selective block of external anal sphincter activation during electrical stimulation of the sacral anterior roots in a canine modelNEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2005N. Bhadra Abstract, Our aim was to electrically activate small diameter parasympathetic fibres in the sacral anterior roots, without activating the larger somatic fibres to the external anal sphincter (EAS). Electrodes were implanted on selected roots in five adult dogs. Pressures were recorded from the rectum and EAS. Quasitrapezoidal (Qzt) pulses for selective activation of smaller axons and narrow rectangular (Rct) pulses to activate all fibres were applied. Sphincter block was defined as [(Pmax , Pmin)/Pmax] × 100%. Roots were also tested with 20 Hz trains. In three animals, evacuation of bowel contents was recorded with artificial fecal material. Stimulation with Qzt pulses showed decrease in sphincter recruitment with increasing pulse amplitudes, indicating propagation arrest in the large fibres. The average sphincter suppression was 94.1% in 16 roots implanted. With Qzt pulse trains, the average evoked sphincter pressure was significantly lower than Rct pulses. Evoked rectal pressures were not significantly different. The mean mass of expelled bowel contents of 51.1 g by Qzt trains was significantly higher than that of 14.8 g expelled by Rct trains. Our results demonstrate that this selective stimuli can activate small diameter fibres innervating the distal bowel and result in significant evacuation of rectal contents. [source] Pudendal nerve stimulation evokes reflex bladder contractions in persons with chronic spinal cord injury,,NEUROUROLOGY AND URODYNAMICS, Issue 7 2007Paul B. Yoo Abstract Aims Although electrical stimulation of the pudendal nerve has been shown to evoke reflex micturition-like bladder contractions in both intact and spinalized cats, there is little evidence to suggest that an analogous excitatory reflex exists in humans, particularly those with spinal cord injury (SCI). We present two cases where electrical activation of pudendal nerve afferents was used to evoke excitatory bladder responses. Subjects and Methods A percutaneously placed catheter electrode was used to electrically stimulate the pudendal nerve trunk in two males with SCI. The response was quantified with recorded changes in detrusor pressure and EMG activity of the external anal sphincter. Results In both individuals, frequency specific (f,=,20,50 Hz) activation of the pudendal nerve trunk evoked excitatory bladder contractions that also depended on the stimulus amplitude and bladder volume. Conclusion The results suggest that selective activation of the perineal branches of the pudendal nerve may further augment the excitatory reflex evoked by electrical stimulation. Neurourol. Urodynam. 26:1020,1023, 2007. © 2007 Wiley-Liss, Inc. [source] Asymmetric sphincter innervation is associated with fecal incontinence after anal sphincter trauma during childbirthNEUROUROLOGY AND URODYNAMICS, Issue 1 2007Beate M. Wietek Abstract Aims Functional asymmetry of pelvic floor innervation has been shown to exist in healthy subjects, and has been proposed to be a predictor of increased risk for fecal incontinence in case of trauma. However, this remains to be shown for different clinical conditions such as traumatic childbirth. Methods A conventional surface EMG system was used to assess the innervation of the external anal sphincter. A symmetry index was used to define the relative EMG amplitude asymmetry of the external anal sphincter between 0 (symmetric) and 1 (asymmetric). Three cohorts were studied: 40 nulliparous women in the third trimester (Study 1), 15 primiparous women within 6 months following vaginal delivery without clinically apparent anal sphincter trauma (Study 2), and 50 women after childbirth-related third or fourth degree perineal tear 6,12 months postpartum (Study 3). Furthermore, all women underwent conventional anorectal manometry. Results Sixteen or forty nulliparous women reported signs of fecal incontinence; however, relative asymmetry was not correlated to symptom severity (P,=,0.345), and not to manometric measures (Study 1). In Study 2, Women who had suffered clinically apparent anal sphincter trauma (P,=,0.07) tended to have a stronger association between incontinence and asymmetry. In Study 3, 19/50 women reported moderate to severe incontinence. Asymmetry and symptom severity were significantly correlated (P,<,0.001). Patients with incontinence had a significantly higher asymmetry score than their continent counterparts. Conclusion Functional asymmetry of anal sphincter innervation is significantly associated with incontinence symptoms, but only after childbirth-related sphincter injuries and therefore, should be regarded as an additional risk factor. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] External anal sphincter contraction during cough: Not a simple spinal reflex,NEUROUROLOGY AND URODYNAMICS, Issue 7 2006Xavier Deffieux Abstract Aims: To assess whether the anal contraction during voluntary coughing is a simple spinal reflex-mediated activity or not. To address this question we studied the external intercostal (EIC) muscle activity and external anal sphincter (EAS) response to cough. Materials and Methods: Electromyographic recordings were made from pre-gelled disposable surface electrodes. EAS electromyographic recordings were made from the EAS of the pelvic floor in 15 continent women all suffering from urgency and/or frequency without urge or stress urinary incontinence, and referred for urodynamic investigation. Electromyographic signal was immediately integrated (EMGi). The abdominal pressure was recorded with bladder and rectal pressure. EAS EMGi was recorded during successive voluntary cough. In three women, we have also recorded EIC EMGi activity since it is synchronous with diaphragmatic EMG activity during cough initiation. Results: In all subjects, EAS EMGi activity precedes the onset of the abdominal pressure increase. The mean latency of EAS EMGi was 615 msec (±278). In the three subjects whose EMGi activity was recorded both on EAS and EIC, the onset of EAS EMGi activity occurred before the EIC EMGi activity (latency ranging from 40 to 780 msec) and before the increase in the abdominal pressure. Conclusions: The present study suggests that during coughing, EAS EMG activity increases before external intercostal muscle EMGi activity. The contraction of the EAS preceding the activation of muscles involved in coughing indicates that this response is not a result of a simple spinal reflex, but more likely the result of a more intricate reflex involving complex integrative centers. Neurourol. Urodynam. 25:782,787, 2006. © 2006 Wiley-Liss, Inc. [source] External anal sphincter responses after S3 spinal root surface electrical stimulationNEUROUROLOGY AND URODYNAMICS, Issue 7 2006Giuseppe Pelliccioni Abstract Aims The aim of this study is to present the normative data of direct and reflex motor anal sphincter responses, simultaneously evoked by S3 surface electrical stimulation. By this method, it is possible to test the functional integrity of the nervous pathways activated during sacral neuromodulation (SNM). Methods Twenty healthy subjects were studied. Motor-evoked potentials (MEPs) were recorded by concentric needle electrode from external anal sphincter (EAS). Electrical stimulation was applied by means of a bipolar surface electrode over the S3 right or left sacral foramina. Results Direct (R1) and reflex responses (R2 and R3) were found at latencies of 6.98, 25.12, and 50.31 msec, respectively. The two first responses were recorded in all the cases; the last response is steadily recorded in 17 out of 20 subjects. Conclusions Our data can serve as reference values for future study in patients with pelvic floor dysfunction. EAS responses following S3 percutaneous electrical stimulation can represent a useful aid in the selection of candidates to SNM. Neurourol. Urodynam. 25:788,791, 2006. © 2006 Wiley-Liss, Inc. [source] Protocol for clinical neurophysiologic examination of the pelvic floorNEUROUROLOGY AND URODYNAMICS, Issue 6 2001Simon Podnar Abstract Clinical neurophysiologic examination of the pelvic floor is performed worldwide, but there is no consensus on the choice of tests, nor on technical details of individual methods. Standardized methods are, however, necessary to obtain their valid application in different laboratories for the purpose of collection of normative data, comparison of patient data and organization of multi-center studies. It is proposed that in patients with suspected "lower motor neuron" type lesions concentric needle electromyography (CNEMG) is the most informative test to detect pelvic floor denervation/reinnervation, and the external anal sphincter (EAS) muscle is the most appropriate muscle to be examined (either in isolation,when a selective lesion is suspected,or in addition to examination of other muscles). An algorithm consisting of standardized tests including a standardized approach to CNEMG examination of the EAS is presented. The proposed electrophysiologic assessment consists of a computer-assisted analysis of denervation and reinnervation features of the CNEMG signal, a qualitative assessment of reflex and voluntary activation of EAS motor units, and of electrical (or mechanical) elicitation of the bulbocavernosus reflex in those patients in whom manual anogenital stimulation failed to elicit a robust response in the EAS. The proposed protocol could serve as a basis for further studies on validity, sensitivity and specificity of electrophysiologic assessment in patients with different types of "lower motor neuron" involvement of pelvic floor muscles and sacral dysfunction. Neurourol. Urodynam. 20:669,682, 2001. © 2001 Wiley-Liss, Inc. [source] Implantation of ethylene vinyl alcohol copolymer for faecal incontinence managementANZ JOURNAL OF SURGERY, Issue 5 2010Jacqueline H. Stephens Abstract Purpose:, The primary objectives of this trial were to evaluate the safety and feasibility of treatment and to gain a preliminary indication of the effectiveness of ethylene vinyl alcohol injections into the anal sphincters of faecally incontinent patients. Methods:, Between April 2004 and February 2006, we conducted a prospective, single-arm, procedure optimization study of ethylene vinyl alcohol injections in 21 subjects with well-characterized faecal incontinence and an intact external anal sphincter at two Australian hospitals. Results:, There was a significant decrease in the Cleveland Clinic Florida Faecal Incontinence Score (CCFFIS) (P= 0.0005) and the Faecal Incontinence Severity Index score (P= 0.005) after treatment. At 12 months post-treatment, the mean CCFFIS had decreased by 37% (P= 0.0021), and 47% of subjects had a ,50% improvement in CCFFIS. There were significant improvements in embarrassment (P= 0.0455) and coping/behaviour (P= 0.0056) domains of the Faecal Incontinence Quality of Life. At 12 months, the mean anal canal length had increased by 29% (P= 0.066), with 40% of patients demonstrating increases of 50% or more. There were no further improvements following retreatment. Conclusions:, Ethylene vinyl alcohol injection into the anal intersphincteric plane is feasible and well tolerated. Improvement in faecal incontinence compared with baseline was seen. Retreating initial non-responders was not successful. [source] Faecal incontinence after lateral internal sphincterotomy is often associated with coexisting occult sphincter defects: A study using endoanal ultrasonographyANZ JOURNAL OF SURGERY, Issue 10 2001Joe J. Tjandra Background: Troublesome faecal incontinence following a lateral internal sphincterotomy (LIS) is often attributed to faulty surgical techniques: division of excessive amount of internal sphincter or inadvertent injury to the external sphincter. The aim of the present paper was to assess the anatomic and physiological factors that may contribute to faecal incontinence following a technically satisfactory lateral internal sphincterotomy by a group of colorectal specialists. Methods: Fourteen patients (nine women, five men; median age: 38 years; range: 23,52 years) who developed troublesome postoperative faecal incontinence were evaluated by clinical assessment, endoanal ultrasonography and anorectal physiological studies (manometry, pudendal nerve terminal motor latency) by two independent observers. The Cleveland Clinic continence score (0,20; 0, perfect continence; 20, complete incontinence) was used to quantify the severity of faecal incontinence. Fourteen continent subjects after a LIS (nine female patients, five male patients; median age: 36 years; range: 20,44 years) were also evaluated as ,continent' controls (continence score , 4). Results: In the incontinent group, the median postoperative Cleveland Clinic continence score was 9 (range: 6,13) compared with a preoperative score of 1 (range: 0,3). On assessment by endoanal ultrasonography the site of the internal sphincterotomy was clearly identified. There were additional coexisting defects, on endoanal ultrasonography, of the external anal sphincter in seven female patients, of the internal sphincter in two female and two male patients; and a defect of both the external and internal sphincters in a male patient who had had a prior fistulotomy. The pudendal nerve terminal motor latency (PNTML) was prolonged in two female patients on the side contralateral to the lateral internal sphincterotomy. In two of five male patients there was no evidence of any occult sphincter injuries. In the continent controls a defect of the distal portion of the external sphincter was noted in one female patient. None of the patients had a prolonged PNTML. The maximum voluntary contraction was significantly lower in the female subjects than in the female continent controls (92 mmHg vs 140 mmHg; P < 0.05), while the resting anal canal pressures and length of the high pressure zone were similar between the study subjects and the continent controls. Conclusion: Troublesome faecal incontinence after a satisfactorily performed lateral internal sphincterotomy is often associated with coexisting occult sphincter defects. [source] The anatomy of the perineal membrane: its relationship to injury in childbirth and episiotomyAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 2 2002Christopher N Hudson ABSTRACT Background Episiotomy during childbirth, intended to protect the anal sphincter, may fail to do so. Furthermore damage to the anal sphincter complex may occur without complete perineal tear. We hypothesise that these particular injuries may occur due to posterior displacement of the anus leading to distraction of the anal sphincter complex from an anterior attachment to the perineal membrane. However, the anatomical basis for this has not been well defined. Objective To investigate the relationship between the anal sphincter and the perineal membrane. Materials and methods High-resolution MRI scans of a female cadaver perineum were performed. The imaging findings were correlated with the anatomical structure identified on dissection and histological examination. Results The perineal membrane was easily identified on MR imaging. Fibres from the perineal membrane could be seen to attach to the anal sphincter complex at the apex of the perineal body. This was confirmed on histological examination and was a deeper layer than that of the decussation of the superficial transverse perineal muscle with the superficial part of the external anal sphincter. Conclusion The upper ano-rectal canal and apex of the perineal body have demonstrable attachment to the free margin of the perineal membrane postero-lateral to the lower vagina. This attachment would resist posterior displacement of the anal canal. [source] A randomised clinical trial comparing the effects of delayed versus immediate pushing with epidural analgesia on mode of delivery and faecal continenceBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 12 2002Myra Fitzpatrick Objective To assess the effects of delayed vs immediate pushing in second stage of labour with epidural analgesia on delivery outcome, postpartum faecal continence and postpartum anal sphincter and pudendal nerve function. Design Prospective, randomised, controlled trial. Setting Tertiary referral maternity teaching hospital. Population One hundred and seventy nulliparous women randomised at full dilatation to immediate or delayed pushing. Methods A total of 178 nulliparous women, all with continuous epidural analgesia, were randomised at full cervical dilatation, but before the fetal head had reached the pelvic floor, to either immediate pushing or 1 hour delayed pushing. Labour outcome was analysed and all women underwent postpartum assessment of anal sphincter function, including anal manometry. Those women who had a normal delivery underwent neurophysiology studies, while those women who had an instrumental delivery underwent endoanal ultrasound. Main outcome measures Mode of delivery; altered faecal continence. Results Ninety women were randomised to immediate pushing and 88 to delayed pushing. The spontaneous delivery rate was 56% (50/90) in the immediate pushing group and 52% (46/88) in the delayed pushing group. Mean duration of labour for the immediate pushing group was 427 minutes compared with 480 minutes for the delayed pushing group (P= 0.005). Eighty-four percent (76/90) of women in the immediate pushing group received oxytocin to augment labour, 21/76 (28%) in the second stage only. Eighty-one percent (71/88) of women in the delayed pushing group received oxytocin to augment labour, 22/71 (31%) in the second stage only. Fetal outcome did not differ between the two groups. Episiotomy rates were 73% and 69% in the immediate pushing and delayed pushing groups, respectively. 26% (23/90) of the immediate pushing group and 38% (33/88) of the delayed pushing group complained of altered faecal continence after delivery (NS). Manometry, ultrasound and neurophysiology studies did not differ significantly between the two groups. Overall, 55% of women after instrumental delivery had endosonographic evidence of damage to the external anal sphincter, while 36% of women after spontaneous delivery had abnormal neurophysiology studies. Conclusions Rates of instrumental delivery were similar following immediate and delayed pushing, in association with epidural analgesia. Delayed pushing prolonged labour by 1 hour but did not result in significantly higher rates of altered continence or anal sphincter injury, when compared with immediate pushing. [source] Assessment of third degree tears using three-dimensional anal endosonography with combined anal manometry: a novel techniqueBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 7 2002A.B. Williams Three-dimensional anal endosonography has enabled sagittal and coronal reconstructions of the anal canal to be matched with longitudinal pressure data, to present a combined picture of structure and function. This novel technique has been applied to a group of women with a clinical diagnosis of a third degree tear. Endosonography showed that only 68% of women had ultrasound evidence of sphincter damage. Anal canal anatomy and pressure profile did not differ significantly between those with and those without sphincter damage, but the anterior external anal sphincter and the puborectalis tended to be shorter and the pressures were lower in those with sphincter disruption. [source] Anal sphincter EMG in the diagnosis of parkinsonian syndromesACTA NEUROLOGICA SCANDINAVICA, Issue 3 2010K. Winge Winge K, Jennum P, Lokkegaard A, Werdelin L. Anal sphincter EMG in the diagnosis of parkinsonian syndromes. Acta Neurol Scand: 2010: 121: 198,203. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Background,,, The role of electromyography (EMG) recorded from the external anal sphincter (EAS) in the diagnosis of atypical parkinsonian syndromes is a matter for continuous debate. Most studies addressing this issue are retrospective. Methods,,, In this study, we prospectively investigated six patients with Parkinson's Disease (IPD), 14 patients with multiple system atrophy (MSA) and eight with progressive supranuclear palsy (PSP) using EMG of the EAS, motor-evoked potential (MEP) to the EAS and EMG of m. gastrocnemius and nerve conduction velocity measured at the sural nerve. Patients were followed up for 2 years to secure correct diagnosis. Results,,, The mean duration of motor unit potentials (MUPs) recorded from the EAS was significantly longer in patients with MSA and PSP compared with MUPs recorded from patients with PD (P < 0.005 for both). There were no signs of diffuse loss of motor neurons or peripheral neuropathy. MEP revealed signs of supranuclear affection in patients with MSA, whereas in patients with PSP the mechanism is a focal loss of motor neurons in Onuf's nucleus. Conclusion,,, Abnormal EMG of the EAS is strongly suggestive of atypical parkinsonism and the pathophysiology may be different in patients with MSA and PSP. [source] Contribution of the pudendal nerve to sensation of the distal rectumBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2005C. L. H. Chan Background: Anal and rectal sensory mechanisms and pudendal nerve function are important in the control of faecal continence. The contribution of the pudendal nerve to sensation of the distal rectum was investigated. Methods: Heat thresholds in the anal canal, distal and mid rectum were measured using a specially designed thermoprobe. Rectal sensory threshold volumes were measured using the balloon distension method. Needle electrodes were inserted into the external anal sphincter. Pudendal nerve block was performed through a perineal approach, and completeness assessed by loss of electromyographic activity. Heat and rectal volume thresholds were measured again following unilateral and bilateral pudendal nerve block. Results: The technique was successful in four of six volunteers. Bilateral pudendal nerve block produced complete anaesthesia to heat in the anal canal (P = 0·029), but had no effect on heat thresholds in the distal or mid rectum. Rectal sensory threshold volumes were also unaffected by pudendal nerve anaesthesia. Conclusion: Anal canal sensation is subserved by the pudendal nerve, but this nerve is not essential to nociceptive sensory mechanisms in the distal or mid rectum. The transition between visceral control mechanisms in the lower rectum and somatic mechanisms in the anal canal may have functional importance in the initiation of defaecation and the maintenance of continence. Copyright © 2005 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Anal vector volume analysis complements endoanal ultrasonographic assessment of postpartum anal sphincter injuryBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000M. M. Fynes Background The aim of this study was to determine the role of anal vector manometry in the assessment of postpartum anal sphincter injury and to establish the most suitable method of anal vector volume analysis for identifying significant external anal sphincter (EAS) injury in an at-risk parous population. Methods A total of 101 consecutive women with a history of instrumental or traumatic vaginal delivery was recruited. Anal ultrasonography and anal vector manometry were performed. Receiver,operator characteristic curves were used to determine the usefulness of anal manometry and anal vector volume analysis in the identification of significant EAS disruption (full thickness, more than one quadrant involved) detected by ultrasonography. Results Seventeen women had significant EAS disruption identified by anal ultrasonography. Anal vector manometry provided complementary functional information. Anal vector symmetry index (VSI), determined by analysis of mean maximum squeeze pressure, yielded 100 per cent sensitivity for significant EAS disruption, with a positive predictive value of 61 per cent. Conclusion Anal vector manometry complements endoanal ultrasonography. VSI, determined by means of the squeeze pressure profile, correlates best with significant EAS disruption identified at anal ultrasonography. © 2000 British Journal of Surgery Society Ltd [source] Temporal endosonographic evaluation of anal sphincter integrity after primary repair for obstetric ruptures: a case for specific training of obstetriciansCOLORECTAL DISEASE, Issue 7Online 2010P. Pronk Abstract Objective, To evaluate primary repaired obstetric lesions of the anal sphincter complex on anal endo-ultrasound within a few days and 8 weeks after primary repair and to investigate in this way the influence of suboptimal woundhealing on the final anatomical result. Furthermore to investigate the relation between faecal incontinence and sphincter defects. Design, A prospective cohort study. Setting, The obstetric clinic and coloproctology outpatient clinic of the Zaans Medical Centre in Zaandam, the Netherlands. Subjects, A cohort of 32 consecutive women with primary surgically repaired 3B, 3C or 4th degree anal sphincter defect after vaginal delivery. Main outcome measures, Appearance of the anal sphincter complex on anal endo-ultrasound within a few days week and 8 weeks after primary surgical repair, i.e. first and second ultrasound, respectively. Evaluation of anal continence, using the Vaizey incontinence score, at second ultrasound. Results, No major wound breakdown was seen and four women had superficial, skin related wound problems. Twenty-eight women (87.5%) had a repaired external anal sphincter on the first and the second ultrasound. Of four external anal sphincter defects on first ultrasound one defect was not present on second ultrasound. The internal sphincter showed a defect on first ultrasound in 11 women and this was still present in 10 on second ultrasound. A total of 11 women had a persisting anal sphincter defect (external, internal or in combination). Mean Vaizey scores were significantly higher in women with a persisting sphincter defect (EAS, IAS or in combination) than in women with no sphincter defects, 2.3 and 0.4 respectively (95% CI 0.1,3.6, P = 0.04). Conclusion, Anal endo-ultrasound may be used for early evaluation of surgical repair of anal sphincter lesions after vaginal delivery. Persisting defects in the anal sphincters, in this series not because of major wound breakdown, can be explained by inadequate surgical repair. [source] Predictive factors for successful sacral nerve stimulation in the treatment of faecal incontinence: a 10-year cohort analysisCOLORECTAL DISEASE, Issue 3 2008T. C. Dudding Abstract Objective, Sacral nerve stimulation (SNS) is an established treatment for faecal incontinence. We aimed to identify specific factors that could predict the outcome of temporary and permanent stimulation. Method, A cohort analysis was performed to identify potential predictive factors in 81 patients who underwent temporary SNS at a single institution over a 10-year period (June 1996 to June 2006). Data were obtained from prospectively collected patient symptom diaries and quality of life questionnaires, operation reports, anorectal physiological studies, endoanal ultrasound images and radiology of lead placement. Results, Clinical outcome of temporary screening was not affected by patient gender, age, body mass index, severity or length of symptoms. The need for a repeated temporary procedure was associated with subsequent failure during screening (P = 0.008). A low threshold to obtain a motor response during temporary lead insertion was associated with improved outcome (P = 0.048). Evidence of anal sphincter trauma was associated with a greater risk of failure (P = 0.040). However, there was no difference in medium-term outcome between patients with external anal sphincter (EAS) defects and patients with intact anal sphincter muscles. Conclusion, Variables have been identified that help to predict the outcome of SNS. The presence of an EAS defect should not preclude treatment. [source] | ||||||||||||||||||||||